2013-08-28 16.18.411

Once the kickstart has been put back together…

The rest is actually a doddle. The kickstart disassembly was only really an excuse to demonstrate how it goes back together (spot the deliberate mistake) but shows how the manufacturers actually thought about the tasks of the assembly and service during the design process, as much as the actual usability of the parts in service as a complete machine.

So, the kickstart is ready to re-fit to the cover, which is already on the bike. There is one small problem on this box, as the oil-filler-‘gutter’ is placed so closely to the nut on the top right that holds the quadrant on, that a little ingenuity or some modified tools are required to get the nut done up tight. The long bottom one and the one on the left are not a problem at all. I used a 7/16″ size long-reach 3/8″-drive socket, as my Whitworth sockets are short, fat 1/2″-drive jobs. NO CHANCE! An appropriate tube-spanner with carefully ground or ‘bashed’ down ‘corners’ on one half will also do the job. There’s always one, isn’t there!! On the MSS, its one of the Magneto fitting screws which requires the special skills of a Gynaecologist to remove unless the barrel is off!

One thing that I forgot to mention, in relation to this issue is the importance (assuming that you are actually working on a functioning and correctly assembled machine) of noting which screws/nuts/bolts came from where. Velocette and other makers seem to have a thrown a veil of secrecy over some procedures to entrap the non-initiated into making mistakes, so that they eventually, in frustration and grief, bring their machine to a dealer to get what was previous to some innocuous repair functioning correctly again!

In this case, I tend to use a bit of cardboard scrap with hole punched in the pattern of the part the screws or bolts came off. This also stops things getting lost or rolling of inadvertently into secret hiding-places that the universe opens up, only to be discovered ten years later when you mop up an oil spill or something…

VERY IMPORTANT if you haven’t worked on Velo box before. There is NO black art to gearbox-rebuilding, but there are a few things to watch out for. The GTP gearbox and some other Velocette items, have a plethora of bolts which seem to have been randomly chosen. This is NOT the case and it is IMPERATIVE that in a gearbox that was formerly working, that the bolts go in exactly the spot that they came out of, WITH their respective and CORRECT washers. This cannot be emphasised enough. In the case of the GTP, the critical one is on the right, over the gearchange-camplate inside the box. IF a bolt that is too long (only needs to be 1/32″ too long) goes in here by mistake, you will LOCK UP THE GEARBOX.

You may get 1st and neutral, but nothing else after reassembly. IF the gearbox is mysteriously locked up after replacing any of the nuts for whatever reason, or having had the cover off, THIS IS THE FIRST THING TO CHECK!

I usually mark that one well and note the washers under it very carefully.


Often there is a double coil ‘Thackery’ washer at this position (above) .

If the box still locks up after trying all the bolts, take the shortest on that you have and place another flat washer under the spring washer already there or grind the end off of the bolt enough to let the box work again. The same goes for the MAC/MOV gearbox, but thankfully not the -5 or above. (MSS/KSS/Swingarm)

2013-08-25 16.13.30

I digress…OK, so the K/S is back on, now the mainshaft-cover-thingy can be screwed on using the appropriate spanner borrowed from a truckie… A one inch socket would also work if the K/S-spring retaining-pin-nut on the top of the boss were not in the way…

Having done that, a quick wire-brush over the nut and it can be re-painted once everything is properly done up, like the rest of the bolts and nuts damaged by the spanners.

2013-08-25 16.20.34

So firstly the gear-change is replaced (easier if the kickstart is moved back a bit to slide the pivot into the hole) and the nut and large washer can be done up on the back to retain it in the bush.

2013-08-25 21.19.46

Then the exhaust goes back on, not forgetting the tube behind the exhaust mount that goes over the square footrest-bolt and the little ring-gasket inside the exhaust at the engine end…

2013-08-25 21.20.19

and the nut on the drop-out for the rear mounting…

2013-08-25 21.20.10

and last of all the footrest itself over the top of the remaining distance tube and the large nut done up tight with a bit of red Loctite on the dry thread.

All that remains is to fill up the gearbox with an appropriate transmission oil and then have a good walk-around the machine to inspect and check that nothing is left over (!), wipe off any extraneous grease or gasket-goo, refit the battery, check the coil-connections and any other things that may have been knocked or taken off during dismantling and she’s good to go!


Job done! (new haircut, too!)

© peter gouws 2013

Made on a mac

Comments Off on GTP all back together

What a pig!

The timing side is really not that difficult anymore, apart from the stupid (duh) mistake that I made with the kickstart… The bane of my life. Why can’t I just leave well alone?? Ah well, better get on with it then. Always a struggle for me, the kickstart quadrant remained a mystery for some time and I wondered how I seemed to need three hands and all my teeth to get one of these fitted satisfactorily UNTIL one day, nearly exasperated, I sat down with one of these in one hand, a glass of ‘works’ lubricant (red) in the other and wallowed in my sorrow! By some stroke of luck, the lighting was such that it showed up something that I had probably seen many times before but not previously ‘perceived’ for what it was. Two small holes in the face of the ratchet gear, usually all gummed up with sh*t and not really that obvious. The curtain before my eyes dropped and now I understood how this was so simple that I had never noticed it before! (BIG ‘duh’)…


This is what it looks like when properly cleaned up. The holes in the face are usually pretty much invisible when caked up with gunge.

OK, so here’s the plan. The idea is to be able to hold the quadrant housing in one hand and be able to turn it while the gear inside remains in the same position (or the other way round – but that needs three hands again…), to enable the milled slot to line up with the hole in the kickstart lever/pedal so that the cotter-pin can be dropped in place…

2013-08-25 15.50.29

In this case I use my lens-ring-removal-tool-thingy held in a ‘Workmate’, as my workbench as such is far away and I don’t have a proper vice up here… BUT, you could use two sturdy nails with their heads ground off and held in a vice at the right distance apart (or even make up a special tool for the job) Actually, a kickstart spring is one of the things that goes in my my long-distance spares bag and with my versatile lens tool, is something that can easily be swapped out, should the damned thing break… Here this is a picture of the GTP parts, which are remarkably clean (yes, I did give it a wipe first, I must concede)

So, the ‘pins’ go in the holes (! I bet you never thought of that!)…

2013-08-25 15.51.01

and it then looks like this. The position of the slot for the cotter is facing towards us running SW to NE on the shaft and will not change in the next pic, as the pins are holding that bit from the back, remember?

2013-08-25 15.51.11

(Oops, I turned the camera angle a bit…) Rotate my hand about 45˚ in a clockwise direction and what HAS changed, if you look carefully, is the position of Smaug’s mountain on the quadrant in relation to the ‘slot’ in the shaft. The ramp has now moved ‘out of the way’…

2013-08-25 15.53.04

… allowing the kickstart lever and cotter pin to be popped on with the other hand without any cuts, bruises, swearing or chipped teeth! EASY! (sorry about the blurry photo)

Next up, the finishing off the bike and then a demonstration of a gearbox complete ‘field-strip’ (about ten minutes) and the trick with the chainguard…

© peter gouws 2013

Made on a mac

Comments Off on Velocette Kickstart reassembly

Let’s get this drive-side finished! YES!

With just a small job to do on the gearbox, to stop the mainshaft falling out! Basically, the lid has to be put on the gearbox: so to start with, first gear is stuck, lubricated, on the end of the shaft:2013-08-23 13.02.45

The gasket face is then cleaned up with alcohol and a smear of Hylomar applied all around.

2013-08-23 13.03.23

The revolting mess on the kickstart pawl is the ‘Assembly Lube’ that I use, which comes in an aerosol and exudes from a thin tube like those supplied with WD40. It comes out like that expanding foam used in the building trade for filling gaps… and then settles to a nice sticky cross between oil and grease. Wonderful stuff! Nice to protect bits and in case I forget to lubricate later, it penetrates nicely when warm, too.

2013-08-23 13.03.57

The cleaned up gasket will be re-used and just gets stuck on the goo as above.

2013-08-23 13.32.07

On goes the lid (with Hylomar also on the inside face) and all the bolts are tightened and the nut put on the end of the mainshaft, the actual reason for reassembling this side and putting the lid on in the first place. The kickstart boss had to come off as I had stupidly taken the cotter-pin out of the kickstart lever before this all started… Something that I will never do again unless I have to, especially with the GTP. The top right of the three screws is even less accessible that on the later and larger ‘boxes, God help me! I’ve no idea how I’ll ever get it tight afterwards!! A good wipe around the joint with a rag soaked in Meths to remove any traces of ‘blue’ and the job can now wait until tomorrow to finish off.

Having replaced the box, it is now necessary to tighten the mountings and re-tighten the primary chain by moving the gearbox back to where it was before (I had to move it forward to wangle the crankshaft-pulley and sprocket on, remember?). Check tension through the hole in the PCC regularly when those big nuts are done up on the top of the gearbox-mount and use the adjuster just to keep tension as you tighten! They can exert considerable force and ruin the whole setup if the chain is over-tight! Once close to correct, a slight loosening of the big ones and tensioning through the adjuster and nip them up nice and tight, not forgetting to check again… Make sure that the tensioner is pulling up against the face of the frame to the rear; if not, despite the tightness of the large bolts, the primary chain could loosen again due to the pull on the top run of chain caused by the blinding acceleration of this powerful little engine! Joking aside, this is important on any bike!

Now to the other side, where the PCC and flywheel have already been reassembled. Now the rear chainguard has to be replaced. The rear chain is first fed over the rear sprocket and the loose end pulled to the front of the bike and placed on the drive-sprocket on the gearbox, returning it about halfway to the rear wheel. Thus, the chain link can be attached, when necessary, on the lower run of the chain. The guard (or should I say both of them – the two pieces have not been disturbed, as the paintwork would surely split and crack) cannot be fitted with the chain ‘done up’, so ithe top run is purposely pushed down into whatever recesses are naturally there, so that it is out of the way, but still on both sprockets. THEN, the rear of the chainguard is fed into the space between the frame and wheel, UPSIDE DOWN, and once clear of the diagonal frame member, can be uprighted by revolving it along it’s length clockwise, with a slight turning of the wheel, taking advantage of the space between the spokes. sounds strange, but works and no paint damaged, either. Saves a whole lot of dismantling going on! The chain link can now be fitted, with the round end facing to the back, as it is on the bottom run…

2013-08-24 14.15.52

Now in place, the nuts and bolts at front and rear and holding it onto the mudguard can be put back with spring-washers and tightened.

2013-08-24 14.15.43

Here is the assembly all done up and the primary chain visible through it’s peek-hole in the casing!

2013-08-24 14.30.29

Next comes the tube spacer on the square footrest-bolt, if not already fitted, then the exhaust can be attached. The one mounting goes on the bolt now, the front and back as before in the head and on the bolt on the rear drop-out casting.

After that, the footrest itself, facing backwards (it doesn’t fit any other way without interfering with the brake-lever!), then the bent flat plate which acts as a stop for the brake-lever, the folded edge vertically on the RIGHT (as can be seen above), then the brake-lever itself (after putting the rod through the rear brake actuating lever-thingy) and the washer which doubles as a bush, liberally greased and placed through and on the gear lever hole, then the washer and nut on the end

2013-08-24 14.30.22

Here it can be seen that the brake-pedal actually ‘resides’ higher than the footrest, which I am nor particularly fond of… If it were my bike, I’d have to find a way to either raise the footpeg a bit or lower the angle of the pedal to be comfortable with it. All a question of what one is used to, I suppose!

2013-08-24 14.30.05

Voila! Drive-side done! Just a few bits of paint to touch up and that was it. Next, the kickstart assembly and footrest etc on the timing-side and all is done, apart from refitting the battery! What a shame! After tomorrow Pud will be able to come and pick it up! I would have loved to have kept the bike for a bit longer… maybe a test-drive… for a week or two, just to make sure everything is OK, you know, for safety’s sake… Have to have a chat with Pud about that! 🙂

© peter gouws 2013

Made on a mac

Comments Off on GTP Drive-side completion

2013-08-22 15.10.41

Now the real fun starts!

Let’s put this jigsaw back together!

Please be patient, there are a lot of hi-res pictures to load on this one!! There are a couple of points to watch that, being a Velocette, it has in common with most of the other models (regarding the clutch at any rate) and a few that are unique to this model, like the re-mounting of the outside flywheel…

Today I want to cover the replacement of the primary chain case and all that this procedure entails… A little different to the average four-stroke Velocette that we all love and know (perhaps intimately).

To start off with, the primary chain case is a but different to the later models. In this one, It also incorporates the dynamo drive in a unique to this model configuration, between the clutch and crankshaft, as opposed to forward of it. I was loth to disturb the assembly of the primary-drive sprocket on the end of the crankshaft from the dynamo-pulley, and so the following procedure was followed: First of all the inside casing had to be affixed to the clutch end of the gearbox on the drive side. The cork Gasket there was examined and found to be good, the surface of that in contact with the gearbox was smeared with blue ‘Hylomar’, non-hardening “aerograde”, which is my favourite since about 30 years for this sort of thing (used to be called something different then). After pressing the cork back on to the gearbox, the FRONT face of the cork has to be smeared with a liberal coating of high-melting-point grease…

2013-08-23 10.37.40

Please notice that clutch thrust bearing has also been replaced in this shot, with a ‘new old stock’ item, whose one face was a bit blemished, so the best side goes inwards to the face the balls in the cage (You may remember that the old one was ‘shot’…)

2013-08-22 15.16.08

Just as a reminder what the race looks like, here with some ‘assembly lube’ sprayed on… before the outboard-facing plain ring goes on.

The reason for the grease is easy to explain: The inside casing has to fit over the the ring around the crankshaft that is on the crank-case and the back end has to be up against the gearbox. The gearbox, however, has to be free to move forwards and backwards to adjust chain tension in the primary chain… SO, after that, the inner PCC can be attached with the 4 screws to the gearbox and wired up, so that they just pinch and a quarter turn back. I used galvanised fencing-wire… The front of the inner PCC is placed over the ring on the crank-case and it should all fit, with the dynamo sticking also through a hole, as well as the square brake-pedal and foot-pedal bolt…

2013-08-22 15.28.32

Here it is, showing the clean inboard side of the Primary Chain Case, which goes up against the greasy gearbox.

2013-08-23 10.51.20

Here it is fitted and nicely wired up, the wires nice and stiff and out of the way of the clutch pusher-offer.

2013-08-23 10.51.30

Here a bit closer.

That’s the easy bit! Next comes whole of the front side of the PCC and the drive off the crankshaft. In this case, I didn’t want to split any more than was necessary, so the drive-sprocket off the end of the crank was still attached THROUGH the outer PCC to the pulley for the dynamo, onto which the actual crank-shaft-flywheel attaches ( just a bit different to the four-strokes!).

To put his on, I first made a new gasket for the Primary Chain Case as shown here:

2013-08-22 16.04.23

The outer shape is easy and is simply traced with a pencil around the perimeter.

While the case is sitting on there, the holes can also be penciled onto the gasket-paper through the holes in the casing, remembering to keep the pencil vertical and sharp!

Cut out, best done with scissors: Don’t forget, in this particular case, that the outside of the chain-case is not the same as the outside of the gasket! Turn it over and you will see that the gasket has to fit INSIDE an edge that has been turned over, and so must be at least 1.5 mm smaller all around…


Cut his first and then measure with a compass (borrowed from one of the children/grandchildren) the width of the gasket required at the face of the inner Primary Chain Case…

2013-08-22 16.09.18

… and transfer appropriately to the paper all around the edge

2013-08-22 16.15.08

… and then cut the inside out, preferably with a scalpel or other VERY sharp knife, or failing that, it can also be done with scissors.

2013-08-22 16.32.43

The holes can be punched using various tools (there are all sorts of hole-punches available. Even one of those leather-punch-pliers will do the job well.

2013-08-22 17.20.16

The inside face of the outer PCC suitably spread with gasket compound and the gasket pressed into place in the outside chaincase.Here it is easy to see the turned-down edge that the gasket fits inside, which is why it had to be trimmed around the perimeter before marking out for the inside cut.

2013-08-22 15.55.47

The clutch can then be placed on the gearbox end of the sleeve-gear

2013-08-23 11.46.19

… NOT forgetting first to check that all THREE pins are still present in the clutch assembly…like I did! When I placed the clutch on the table, the one pin dropped out and I didn’t notice until I had fitted the outer… another 15 minutes undoing all the screws and then taking the clutch off, put the pin back in and re-assemble… Happens every few years or so… No one else has EVER done that before, though, I suppose!

2013-08-22 15.56.58

The clutch nut is then screwed on so that it all doesn’t fall off (using here a tool actually designed to remove lens-rings on cameras!)

2013-08-23 11.26.40

The primary chain is then rotated onto the clutch and readied to be put on the sprocket on the inside of the outer chainguard.

Now comes a tricky bit… The perimeter of the inner chain-guard then has gasket goo applied, the front sprocket is brought closer and has the chain rotated onto it and the sprocket/ pulley is pushed over the crankshaft end (assuming that the gearbox has been previously positioned so far forward to allow this!!)

2013-08-23 11.28.19

OK, after this, assembly of the PCC is simple enough, the screws are replaced in their appropriate holes and all is good.

2013-08-22 17.31.05

Now the ‘cotton-reel’ is replaced on the front of the PCC/Engine mount

2013-08-23 11.41.05

The dynamo pulley and belt can now be replaced. Put the belt on the crankshaft pulley and the other end in the dynamo pulley and slip the pulley over the shaft with the belt on, unless you want to undo everything and do the rotate-to tighten procedure all over again. It’s no good putting the pulley on first, obviously, as the belt WON’T won’t fit over the lip – believe me!

2013-08-23 12.15.31

Tighten the nut on the pulley, of course, before putting the cover on over the top.

2013-08-23 12.33.23

… and the large nut that holds the pulley on the crankshaft can now be put on and tightened. Clean the threads meticulously and screw the nut on tight.

At the first attempt, I found that the nut turned the crankshaft before tightening on the pulley, so the pulley needed to be driven onto the taper of the shaft to affix it first, to avoid premature rotation of the engine, which slightly hinders the tightening of the nut…

2013-08-23 12.30.59

For this, a large, deep socket was used and cautiously but firmly whacked to seat the the pulley onto the taper, so that it did not rotate…

Eventually it worked, the nut was tight and the flywheel could then be attached by the six nuts.

2013-08-23 12.50.45

The washers under the nuts were cleaned up

2013-08-23 12.53.57

… and the nuts done up opposite to one another, to pull the flywheel evenly into the recess.

2013-08-23 12.40.12

Once pulled in and checked for egocentricity (hic!), the nuts were removed again and a spot of Loctite applied, the nuts now done up for real, ready for painting!

Well, that was about it for now, the mainshaft is then dutifully replaced in the gearbox and tomorrow, the rest of the assembly will be updated!!


© peter gouws 2013

Made on a mac

Comments Off on GTP Primary Chain Case re-assembly

2013-08-18 15.58.01

Well, blow me down. Four days and nights I have been beating myself up about not stripping the ‘box while it was out of the frame and at four this morning, it finally got me.

So I decided that, between everything else going on here (including storms, blocked drains, trees falling all over the place fetchin’ an’ totin’ for the parents, that I’d finally ‘do’ it. The box had been sitting there looking at me reproachfully every time I went past it (about 40 times a day) and so I grabbed it had another look. There was a sort of light-browny sludge and bubbles of water sitting in it and oozing out of one of the corners and that finally tipped me over the edge. All had to come out, if only to clean it all properly, and with that much water-ingress, there was bound to be more to discover inside.

The only successful way to get this apart is first to extract the two pins from the selectors, AFTER making sure that the gearbox is in neutral (this makes it a lot easier, believe me!). To remove the pins, they are pushed/punched out from the clutch-side of the box, NOT pulled out with Mole-Grips or any other Neanderthal method… once out, and having pulled out the mainshaft (if not already done), the first gear BK9/4 will now be sitting loosely on the top, or already have fallen on your foot… the other two gears formerly on the mainshaft can now come out, with some clever tilting and skewing of the selector and if necessary a few expletives as lubricant (works very well and always good to have close at hand!).

The layshaft and selectors are a bit of a bind to get out, even if practised, due to the lack of space in this rather small casting, but a method is soon found to disengage the selector and twist it all out. Don’t try taking the sleeve-gear out first, it doesn’t work. Strangely enough, reassembly is always a lot easier than dismantling, even if you’ve never done it before!

Now I remove the swivel pin (remember the actual culprit in the story) and remove the selector plate, being careful not to let things go ‘ping’ inside and fly about the place. For the less confident, a tea-towell over the opening stops any errant bits (usually the click-stop pawl and the ‘biro’ spring) from becoming ballistic and subsequently losing the spring (I’ve never done that before, of course!).

Once that is all done, the whole lot can be cleaned and inspected:

I start with mineral turpentine and then use thinners for nasty grime and then wash it down with methylated spirits, but I suppose everyone has their own favourites. For reassembly a smear of sewing-machine oil suffices to keep things lubed.

2013-08-18 15.50.18

So this is the inside of the box after wiping out and cleaning, the camplate still engaged but the pin already unscrewed, which is why it is a bit ‘skew’.

2013-08-18 15.51.27

Outside cleaned of all the crud that was on it.

2013-08-18 15.51.46

and the clutch end, without disturbing the cork, which is all intact.

2013-08-18 15.58.53

OK, here is the camplate properly, so that you can see it! The pivot is obviously missing from the centre and the selector-pawl is notched in the ‘neutral’ position.

2013-08-18 16.10.40

The plate removed and showing what lurks behind it, which is all OK. The ‘Biro’ spring (vertical) will also be ordered for later… the pivot bolt (with Loctite!) is seen here already screwed back in from the outside… tightened up and then repainted black again!

2013-08-18 16.13.26

The plate replaced, making sure that ‘neutral’ detent is engaged with the pawl (neutral is always the shallowest indentation, and is the second one from one of the ends (depending which plate you have… WD and postwar ones were generally for all models the other way round for the gearchange ‘one-up, three down’).

2013-08-18 16.12.10

This one shows the detent for first gear ‘occupied’ by the pawl… see how the one for neutral (2nd notch) is smaller?

2013-08-18 16.00.28

Obvious damage to layshaft gears from sitting in watery oil for decades…

2013-08-18 16.01.51

… and the same on the mainshaft gears. This means that in the long run, a new set of gears (identical, by the way to the MAC/MOV cluster) will be sourced for replacement at a later date. These will run fine for a long time yet, even if they aren’t pretty.

Having checked all the bearings, it’s time for reassembly!

2013-08-18 16.15.19

First the sleeve-gear is replaced (shown here, the gearbox is upside-down)

2013-08-18 16.23.19

Then the layshaft gears and selector (which looks very home-made!) can be twiddled into place (easy if it’s in neutral, remember!!)

2013-08-18 16.24.44

Then the second and third for the mainshaft are lain in place atop the sleeve-gear, also slipping the selector in the slot (you will have to lift it a tad to position it right, you’ll see!) and, as shown here, the pins also then need positioning (shown here not yet all the way in) pretty darn quick to keep everything in position, as the lid can’t go on yet, until the Primary Chaincase is in position… Don’t want it all falling out again, do we!?

2013-08-18 16.39.03

Now the ‘right’ way up, with first gear on the mainshaft, just for the picture, and with the distance-ring on the layshaft end, ‘inside’ the kickstart ratchet:

2013-08-18 16.52.47

That’s the one I meant!

2013-08-18 16.50.56

having replaced (and painted) the so-called ‘striking-lever’, the whole lot can now be hung back on the frame,

2013-08-18 16.54.00

the adjuster slipped into place and the two large bolts done up enough to hold it all together.

2013-08-18 16.56.30

Now the clutch cable can be replaced in the doodad inside the box, but first gear has to come out for this, so that a ‘digit’ can be used to lift the end of the lever far enough out to slip the nipple of the cable through the slot into the hole…

2013-08-18 17.00.17

Don’t forget to put the tower on the cable (as seen in the pictures above) before slotting it in (already in the slot here), or the clutch doesn’t really work that well and you might have to dismantle things later if you didn’t notice the ‘nutty slack’…

2013-08-18 17.01.27

Here the cable in place, the lever back inside the gearbox ans the tower ready to screw back on. This invariably damages the paint on the tower -sorry, ‘cable-stop-holder’ (as there aren’t any flats on this one), so once tight, it is also rubbed over with emery and repainted black to stop corrosion.

More tomorrow!!

© peter gouws 2013

Made on a mac

Comments Off on GTP full gearbox strip-down

So now I have the bike sans gearbox and drive-components on my improvised stand. And what a beauty it is, too. I must admit to having fallen in love with it, such grace and elegance, so well thought out and the solutions to save weight at NO expense to rigidity of the whole plot, simply genius! And what a joy to work on!

2013-08-15 09.04.28


This should be the first thing drummed into us at school from the very first day onwards and for every day after that. If we were to learn only that, it would save us more time, money and stress than anything else in our education – in fact, probably more everything else put together (if we haven’t grasped that one concept)!!

What am I babbling on about, you might well ask? Ah yes, we’ve all heard the ‘stories’, the ‘old chestnuts’ and wisdom of ages passed down from generation of ‘Veloist’ to the next, like “90% of gearbox problems are clutch problems” etc, well, here’s a new one! What happened here, I have never seen happen before, but I must admit, is the result of a stroke of genius by the designers of these gearboxes, for whom we should be ever grateful.

Let’s start at the very beginning: Pud came to me a few weeks ago and said that he’d like me to look at his GTP. The gearbox wasn’t right (he’d seen the job I did on one of mine and knew that I wouldn’t butcher it). It was ‘stiff’ were his words, and on further inquiry, the word ‘tight’ was also mentioned. Oops! Not good.

These two words conjure up uncomfortable feelings at three in the morning on the M6 in January at minus whatever on the way from Birmingham back home, with a long way yet to go, with the bike getting progressively slower, despite the road being level and the ‘tap’ turned on at the same opening. Uncomfortable, because it meant either that the engine was about to seize, or the gearbox. Dammit, put the choke on a bit (to help cool combustion) and ease the throttle about a third and gain some time to think… I would prefer that it is the engine, out here in the dark in the middle of nowhere, if I’m honest, as it’s easier to fix. Only one way to find out! Close the throttle, pull the clutch. If the bike lurches to a halt and the engine is still spinning, it’s the gearbox… and if the bike decelerates at a ‘normal’ rate and the engine falters or stalls, it’s the piston stopped going up and down or very tight.

I have wandered off again, sorry… Back to the gearbox in question and my ‘assumption’, based also on the assumption that we both spoke a common language, this is what I understood by ‘tight’, based on some various experiences in my shady past. And so I thanked him for his trust and graciously took on the job to discover which naughty bearing was causing the problem…

The story so far I hope that you have enjoyed having recorded here on the last two blogs and is ‘history’, so to speak.

With the box on the bench, I could now go about taking the thing apart to see what is wrong. The Sleeve-gear bearing can, technically, be removed from the clutch end in situ and to be honest, this was my main suspicion for the problem. I have a couple of L35N Hoffmans and sundry other bearings here, so not a problem, but it IS easier to take out once all is removed. Before the gears can all come out, the ‘striking lever’ BK65/3 has to be removed along with the camplate pivot, BK64/2. Having done that, I thought, just pull out the ‘pins’ and the rest can be pulled out… I had already removed the nut on the striking lever (almost) while still in the frame, but it was all a bit close, which I why I took the box out. Makes it all a lot easier, SO, a few twists and it came off and then…

Wait a minute! What’s this?!

2013-08-14 13.51.17

2013-08-14 13.50.58

I hadn’t actually seen this while it was all in situ in the frame, but now… Elementary, my dear Watson! (and the sharp-eyed amongst you would have spotted it yesterday on one the photos already – but I didn’t want to spoil a perfectly good new blog for today by mentioning it!). Could this be the reason that he was having ‘difficulty’ with the box? Indeed, but very different to what I had erroneously ‘understood’ (assumed), the stiffness was not so much IN the box, as outside, and actually was a difficulty in SELECTING gear, not in the operation of the transmission as such! OMG!

So simple, and yet would make the bike very difficult to ride. In fact, IF I HAD BEEN ACTUALLY LOOKING FOR IT, I could have seen it before, BUT, on the other hand, it would have been nigh on impossible to remedy with the gearbox in the frame anyway… C’est la vie! The geniality of the whole design, is that the it is MEANT to be so, as the striking lever prevents the pivot from falling out in the road somewhere between here and Novgorod in the middle of the night. Also very nice is, that it is not permitted to unscrew enough to cause the camplate do ‘disengage’ with not only disastrous, but expensive consequences, quite apart from a suddenly heightened awareness and skill required to overcome a locked up back wheel at speed. (Even worse if the chain brakes under the strain, catapulting you forward freestyle for a second, until it wraps itself around the wheel, locking it up again!) What fun. You don’t have to ask how I know, do you?? (Don’t worry, it wasn’t on a Velocette!)

So, the mystery is solved and here are a few shots to show what happened in more detail. SO don’t forget to light a candle for those long-gone designers of these boxes, who went to such lengths to protect us from the evils of gravel-rash, at least until the gearbox casing design was changed for the swinging arm models! At this point, it might be worth noting that next time your Venom/Viper/Whatever gearbox is out, it might be worth wiring or ‘Loctiting’ this particular part in place, just in case!

Having said that, I have NEVER seen this happen before, but it only has to drop out once, to spoil your whole day!

2013-08-14 15.32.36

This is how it ‘should’ look, as far as the distance between the parts is concerned, anyway. I still haven’t taken off the lever and cleaned it yet, only screwed the offending ‘nut’ back in…

2013-08-15 09.10.15

The offended striking lever from the inside, showing some road crud and the removed paint and metal filings due to the contact with the face of the pivot…

2013-08-15 09.23.16

This is what it looked like after a clean-up. Quite obvious rub-marks and some wear on the finish.

2013-08-15 09.10.25

The offendING pivot nut, which I am assured used to be painted black…

2013-08-15 09.21.37

To effect a cure, it was agreed that I unscrew the nut as far as possible without disengaging it all inside, clean and dry the thread and apply some blue ‘Loctite’, before doing it up tight again. *Note the shim/washer under the nut, which serves 2 purposes: to prevent the nut damaging the alloy of the casing and to correctly space the cam-plate inside on the shoulder of the pivot, lining everything up nicely inside, which greatly assist the smooth function of the box. The wrong shim, or none at all, could certainly have a negative influence on it all, something to bear in mind on these early gearboxes!

The bearings in the box Pud assured me had only done seven or so thousand miles and despite some water ingress through the clutch cable tower, would not require changing. The gearbox was quiet and smooth and unlike a bigger bike, the box has a relatively easy life. When he bought it 35 years ago, it was already 35 years old and had done COSIDERABLY more mileage and the original bearings were still fitted and working fine… So no reason to dismantle or disturb anything any further, after the “if it’s not broke, don’t fix it” principle, which I thoroughly agree with! Anyway, if it does play up at some time in the future, I am hoping that I might have a further opportunity to work on the bike again, which I would greatly look forward to!

2013-08-15 09.25.06

Always nice to have and to use the right tools for the job: Above, the massive spanner for the nut!

So everything will get a good wipe-over and clean, the gearbox will be re-assembled and mounted in the frame, the nuts as necessary re-coated with an oil-based black paint after assembly. Tomorrow the clutch and chaincase re-assembly are the subject of the final episode on the repair of this wonderful little machine. I WANT one!


Oh, and here, just by way of anecdote, have a look at the registration / tax document of the GTP; Notice anything slightly unusual??

2013-08-15 09.05.53

What is it registered as (since new)? A Velo-Solex?? Isn’t that a French bicycle with an engine balanced on the front wheel, that runs on garlic-cloves and a bread-stick?? Just goes to show that the officials then, as now, had absolutely no idea what do with a name like Velocette! And that in 1939!

Dr. Peter saying toodle-pip for now!

© peter gouws 2013

Made on a mac

Comments Off on GTP Gearbox cure…


It is certainly not every day that anyone gets the chance to have a look at and dismantle a Velocette single-plate clutch, as fitted to the pre-war MOVs and the GTP series of bikes, so I thought that while I’m at it, I could take a few pictures and document what it looks like and how it goes together… one never knows when it might be of use to someone. It is often said that most Velocette gearbox problems are actually clutch problems, but looking at this, there is actually very little to cause any problems at all. Altogether a wonderful setup, and the sturdiest little clutch I’ve ever had the pleasure to work on or with. Talk about robust! No plates to warp here, that’s for sure. The simplicity of the design is genial and it is no wonder that Veloce continued with this setup right until the end – albeit with a few changes along the way, as a result of what I believe is called ‘progress’.

Above is the bare clutch, with the mainshaft about to be removed…


… as shown above with it already out, from the ‘other end’ of the gearbox.


The spring-ring is undone with A61/2, a peg-spanner, which you either have or have to improvise. Do NOT hammer it undone with a screwdriver in one of the holes, PLEASE! Here it is shown almost about to fall off


and here is the ring of sixteen springs hidden behind it, which do all the work (Thruxtons have 20 springs)! Unlike the later restrictions in the availability of larger-diameter spring-wire after the war, which led to designs like the Vincent’s clutch on the series B etc, this was actually designed like this ‘on purpose’ a LONG, long time before WWII… I wonder where Uncle Phil got his idea from…?


So here on the left is the solid front plate removed With the collar and springs still attached and on the right, the plate behind it with the cork friction-material, the bearing-ring and the three actuating pins in the depression around the central boss.


This is what they look like from the ‘other side’. The working of the clutch itself is probably the most talked aspect of Velocettes the world over… and I see no need for further dis-assembly at this stage. Maybe later?


Now that the clutch is off, the screws mounting the chainguard and the clutch actuating ‘ring’ are revealed On the left of the protruding gear (also wired on) is the fulcrum of the ring.When the clutch lever is pulled, this end of the ring is pushed off the flat back towards us (as in ‘outboard’) from behind the tab on the right, basically ‘skewing’ it and therefore separating the driven and driven plate(s) from contact with one another…. The chaincase retaining-screws have been wired to stop them inadvertently rotating and undoing, a somewhat embarrassing and expensive, if not dangerous experience, I could imagine…


Just for reference, the ‘business end’ of the dynamo, without the pulley, which on the GTP sits IN-side the Primary Chaincase


Here just a view of the whole plot with the chaincase removed, showing just how minimalistic everything is. Veloce went to great lengths do devise a very stiff and light setup to the whole machine.


Looky-looky through the hole left by the shaft and showing the gear on the other side which has toppled to the right. Obvious here is also the road-grunge and dirt that this machine accumulates. Not a bike that sits languishing in a posh living-room on a stand, believe me! This machine does some serious touring, with dents on the mudguard at the front where the Webb forks bottom out over railway-lines at speed… (unintentional, but nevertheless there…)


Interesting. these are the four screws and the fencing wire and an extra nut off the chaincase inner (the nut held the pillar that the dynamo-pulley-guard screws on to on the perimeter of the chaincase. I hadn’t noticed at first until it fell, but while looking and preparing to take a photo, a movement caught my eye… something had fallen off! And here it is with the other bits: A ‘hobby’ razor-blade… I’ll have to ask Pud about that, it might just have been the right thickness to stop something rattling… Who knows!!


Well, now the guard is off the other side, I can ‘drift’ the pins out that hold the selector-mechanism in place, for ‘ease’ of further dismantling. Those are them on the right of the picture, sticking out of the innards, not yet completely removed.


And a shot of the clutch actuating cable, having removed it from the lever in the box (in the ‘ole), after unscrewing the tower (the black tube lying on the top of the box) it normally hides in. This is actually the only weakness with all the Velo boxes of this era, as the tube offers an opportunity for water to enter the gearbox at this point. Water drips down the cable when riding in the wet and goes in through this hole. The remedy is the type of grommet-thingy also found on handlebar-levers and the tops of carburettors. This one’s grommet was dried and cracked and probably the reason for the small amount of whitish-goo in the gearbox. More of that on further inspection!!


Just for reference, this is the way that the gearbox mounts on two rails on the frame, the screw is used to adjusts the chain-tension and fits on an appropriately shaped part of the frame just forward of the rear mudguard.


The clamp on the top of the ‘box…


…and here the gear-change leverage on the outside (front-facing) part of the gearbox, very difficult to get at and impossible to remove in situ, which is why I took the trouble to take it all out in the first place!


Before going any further, I just want to secure the thrust bearing inboard of the clutch before removing the sleeve-gear and everything else… here it just looking out of the gearbox casting and below, removed and place in safety somewhere that I can keep it clean and find it later for re-assembly (yes, the inside ring is still not out, I know… that’s still sitting on the sleeve-gear!



Well, that’s it for for Doctor Peter’s clinic today, folks! Hope you enjoyed today’s episode! More coming soon on the same channel, stay tuned!!

© peter gouws 2013

Made on a mac

Comments Off on GTP and pre-War MOV single-plate clutch

Own up!

Anyone out there ever worked on a GTP that really ran well?? I haven’t and in fact have never had one of these ‘go through my hands’, so it is something completely new to me altogether! Apparently the problem with this one is a ‘tight’ gearbox, which has to be looked at, since Pud uses this on a regular basis; he just does not have the time or the room to work on this at present, due to ‘other priorities’. I don’t know if he is actually only being kind in giving me an opportunity to learn something new (- At my age! Happens every day, but not like this!) or really hasn’t the space: Whatever the reason, here it is and I am very grateful – thanks, Pud!!

And, as you saw in the last hastily assembled blog and the photographs, it is plain to see what a fine example of the marque and model in question.

So to the gearbox problem. Nothing can be gained by stripping the box in the frame (if indeed it is possible, it only makes re-assembly more difficult!), so the process of removing it and dismantling it has to be started somewhere! First of all, the exhaust and all the other parts that are ‘in the way’ on the timing-side have to come off. The exhaust is held on with a mounting onto the ‘drop-out’ of the frame at its rear end and the threaded ring on the exhaust-port on the engine end (with a copper ring-gasket inside), with a bracket hanging from inboard of the foot-peg in the middle, which has to be removed along with the distance tube, before the pipe itself will come off, of course. The pipe does not have to separated from the silencer to remove it, have a look at the picture and you will see how it works!

2013-08-01 13.55.282013-08-01 13.54.46

The gear-change linkage is removed for easier access and storage of the bits, by unscrewing the nut off the linkage from the actuating lever on the front of the gearbox

2013-08-10 16.08.50

… and the screw and washer that hold the lever mechanism on behind the big bush on the top of the gearbox (as illustrated below, replaced for clarity in the photo!).

2013-08-10 16.09.16

Now with that it out of the way, I removed the cotter-pin from the kickstart (not actually necessary, but means that the lever can be swung out of the way. The disadvantage is that it is a fiddle-faddle to get it back in later). Now all the bolts can be removed from the front cover, not forgetting to remove the large nut (B3) from the cover, to get at the nut on the end of the mainshaft (B5/4) which might make removal of the cover difficult, otherwise! Note also, by the way, the CORRECT B60/2 kick-start and foot-change-rubber with the OPEN end… different to that so often marketed with a closed end: One of my future projects, soon to be revealed!

2013-08-01 14.00.362013-08-10 16.09.51

(The picture directly above shows the B3 removed and the cover taken off, with the gear-change-pedal replaced for orientation of the parts, and with the kick-start swung out of the way!)

OK, that has sorted the timing-side, now round to the drive side, where there is a bit more to do, starting with the footrest and brake-pedal, Exhaust and then the various bits of tinware like the chainguard , which is a pain to remove!! Nut and bolt at front and rear and not forgetting the one holding it in the middle to the mudguard skirt. The whole thing is a bit easier if you take the final drive chain off before you attempt to get the guard out in one piece, if that’s what you want to do (which I do…). Splitting the two while on the bike is fine if they are a sliding fit, but beware of chipped paint and skinned knuckles if they are tight. (How I know?) So as with many before it, this one is removed in one piece, the trick being to twist it around at the right moment so that it is upside-down as the last part is extracted carefully from all the sharp bits just waiting to leave their mark on someone else’s paintwork…

Phew! That’s done without blessures and now it allows the removal of the main-shaft and sprocket from this side of the plot, to be put somewhere safe. Next is the flywheel and chain-guard. (this picture before removal of the chain-guard, which can be seen on the right!)

2013-08-01 13.58.01

Flywheel first, as the chain-guard is behind it as well as the cover for the dynamo drive-belt (KA93/7), another piece of ‘tinware’ that is unique to the two-strokes – of which there are many! I was a bit wary of the flywheel, but not seeing any other impediment to its removal apart from the six nuts on the centre of the boss, these were dutifully removed. Still sat very tight… Oh well, giving it a gentle bash with a nylon mallet from the back didn’t help, so I started undoing the large nut at the centre and in ‘unwinding’ it so the flywheel was pushed off the shaft by the inside of the flange on the nut and came off relatively easily, as did the aforementioned cover which is held on with two nuts, the dynamo pulley with the usual central nut.

2013-08-10 17.30.09

The flywheel removed, showing the flanged nut that was on the INSIDE, which when unscrewed (normal right-hand-thread, by the way) pushes the wheel off the shaft: Clever!

Now the larger-than-the-hole-in-the-primary-chain-case boss had to be removed, before the chain-case itself could come off (duh). This, according to the parts list, is held on a taper on the shaft, so will require a puller. The problem seems to me to be, how is the sprocket attached and how to separate them. No ideas from the parts book either. The front of the flywheel-mounting-boss/ belt-drive-pulley is shown with six radial holes as is the sprocket. Convenient would be if the sprocket was held on the inside of the chain-case to the ‘back’ of the boss with bolts that ran through the boss to the front, where the flywheel would then be fixed with nuts on the front. That would make sense, because then, once the flywheel was removed, the boss would still have to be pulled off the shaft, but the sprocket and chain would remain inside the chain-case; HOWEVER: We have a problem here!

The front of the boss had six studs coming out of the front… I think,

2013-08-10 15.26.33

(This is it AFTER removal!)… that show no sign of movement or being a sliding or loose fit in the holes and the sprocket (unseen on the IN side) seems to be ‘well attached’ to the flywheel boss still. Oops! I shall have to be VERY careful removing the pulley from the shaft, for fear of doing any damage to the chain-case or sprocket. Ah well, you only live once (and Pud can only kill me once, even if very slowly), so the puller was set and the boss pulled off the shaft with a ‘crack!’ As I thought, the chain and sprocket were still attached, but no damage done. Breathe in, breathe out!

So, what now?? The chain still being attached made it all a bit more difficult to separate the halves of the chain-case, even after removing the 16 screws and one pillar from the perimeter. Oh, and another ‘oddity’: Mounded on the engine plate at the front of the chain-case is a strange-looking ‘cotton-reel’ fitting. Imagine a turned ring of about an inch in diameter and half an inch thick, with a slot turned in it, the width of the two chain-case halves around the outside edge… and deep enough to act as a stop, when the chain-case edge is inserted into the gap. So, have I lost you? Take a look at this (unfortunately taken with flash): The button is clearly visible on the left hand side (front edge) of the chain-case, central in this shot:


This also doesn’t help when trying to split the front of the chain-case from the back, if you can follow me because it effectively pinches the front of the cases together, and so also has to be removed before I can go a step further.

Well, I managed it. I had to go around the other side and loosen the gearbox mounting and screw the gearbox closer to the engine to slacken the chain and then fiddle the now looser chain off the front sprocket by the old ‘divert and rotate’ trick, which is all that was possible in the confined space, despite removal of the ‘cotton-reel’.

2013-08-10 15.25.00

So this is it, with the main-shaft replaced (actually the safest place for it while all this stuff is ‘lying around’)

2013-08-10 15.26.52

This is the INSIDE of the cover, showing that the sprocket is NOT held captive by through-bolts, but definitely by the short studs as illustrated in the parts-book…

2013-08-10 15.27.11

And here the single-plate clutch arrangement on all the pre-war two-strokes and the MOV, still assembled. More of that in the next episode! (Please note that this is NOT the normal position for the gearbox-mainshaft…)

Hope you enjoyed that, I did. This is certainly not a bike that everyone has the chance to work on and so it is a great pleasure and treasure to be able to do so! And so, until the next time, Doctor Peter signing off for today…

© peter gouws 2013

Made on a mac

Comments Off on GTP Gearbox-strip #1


This coming week looks like being an interesting one!! ‘Pud’ has decided to let me have a go at the gearbox on his early 1939 GTP, which is a bit different for me, as I’ve never actually worked on one of these bikes, or one of these gearboxes, either (the same internals, though as the MAC and MOV of the same era! A whole new ball-game! The project will also allow me to take and post some archival photographs, which might be interesting for those looking for an example to emulate when restoring their own bikes, should anyone have one out there. It’s a bit strange, Pud’s GTP is the only one I have EVER seen that actually runs!! All the ones I have seen up to now ‘still had problems’ that had to be sorted out, before they could be called ‘runners’ – probably due to the plethora of changes made during production and different parts ‘available’; getting a proper set of bits that actually work together is, apparently, a major challenge!! Pud’s bike is the xception to prove the rule! His has been meticulously kept in original condition and so is a very good yardstick for those seeking something unadulterated by previous owners or tens of years rotting somewhere and being used as a donor, or just sheer pilfered off!! All the handlebar controls, including the push-me-pull-you throttle is intact and working, the ‘perches’ for the switches etc are all there.

Altogether a pleasure to have in my (improvised) workshop at the parent’s place. Here anyway, are the first pictures, before I start stripping the box. Afterwards, I will do some ‘proper’ archival shots for the ‘album’ for would-be restorers and ‘comparers’. This really is a very nice, original example. Pud has had the bike about 35 years and has restored it conservatively, as is his wont. You only have to see his K-model (also on this site in the photos section) to see the standard of his work. He keeps all he can and repairs everything possible, but only restores what is necessary! How many times have I heard that someone has replaced everything possible with new parts and then maintain that their bike is absolutely ‘original’!!

You would be hard-pushed to find anything on the bike (apart from tyres/chains/oil etc.) that was not made about the time that the bike left the factory or very soon after. In Australia, we have one distinct advantage in regard to the ‘pre-war’ era bikes: most of the parts were shipped here prior to the war by Veloce, to avoid it being ‘commandeered’ by the government for the war-effort. Very far-sighted of the family and certainly very useful down here! Before I came here 8 years ago, I had no idea of the situation and it has certainly been an eye-opener. There are a great many bikes and enthusiasts ‘down under’, more than in the UK even, for the pre-war stuff, and a wealth of expertise in the racing department, too! There are probably more KTTs down here (and regularly raced!) than the rest of the world put together! Whatever, here are the first shots of Pud’s excellent GTP, for those interested… Lots of photos, so please be patient regarding loading.. it takes time, these are all full resolution photos!

2013-08-01 13.54.25

My excellent work-stand, a shipping-crate on its side (so that I can use it for storage under the bench!) with a door screwed to the top… Very hi-tech and a just a bit cheaper than the rather more expensive hydraulic versions available…


a nice shot of the engine and gearbox.




Exhaust and general arrangement at the rear end (the black insulation tape visible on the stays is to retain the wiring to the rear light)


Rear Number-plate…


Front 3/4 view of engine from the ‘drive’ side:


Just some random shots with little comment for the moment…



Original ‘pimply’ battery-housing


Carb and Voltage-Regulator


Brake-pedal arrangement


‘underslung’ pillion footrest mounts on earlier models


Drive-side rear brake and wheel-spindle arrangement.


Miller Voltage Regulator cover


Original ‘John Bull’ kneegrips…


Nice switchgear


Original dealer water-slide transfer (‘decal’)…


Also on the top of the toolbox


Oil Tank cap


Gearbox general view


Gearbox mounting and clutch cable.


Miller Genny…


Points cover and engine number


Push-me-pull-you Carbie set-up


…and relevant throttle arrangement…


Single-sided damper arrangement for ’38-’39




Perch horn-button



Mudguard ‘skirt at the front…



Interesting valve-cap!


© peter gouws 2013

Made on a mac

Comments Off on Anyone for GTP?


Early MSS ‘Map of Africa”

Well, while the blog as such hasn’t been moving forward in the sense of regular postings, there indeed has been a lot going on in all sorts of ways in the background.

There have been a couple of new ‘events’ and some changes in emphasis, as well as a very much consolidated idea about the bike that I’m restoring and the use that it will be put to!

Let’s start off with the bike, shall we! Since I intend to put in some serious mileage with the bike – more of that later – there are some conditions that have to be met. It is arguable that the British made the best bikes of the period in question, as is what is the ideal size and capacity for a motorcycle. These questions are not merely a matter of taste (though that has to weigh very heavily for the extremely personal choice that a motorcycle is or becomes), but a question of practicality and what the bike is going to be used for. It is often quoted that the 350cc size is the best compromise between power, weight and ‘nimbleness’, which would hint at them being the best ‘all rounder’. In General, I would broadly agree with this statement and have done many a happy mile on 350s – not least of which my 1938 Ariel, which started life as a 500 and was then ‘promoted’ to 350 for ease of use and tractability, especially in a succession of -20˚C winters in Germany. The original idea was to use the 500 in the summer for the longer trips and the 350 engine just swapped out for the winter for the local daily trips to work in snow and ice… Once the 350 was in there, I never needed to change it back, as I only ever rode ‘solo’ with the bike, anyway!

Ah the good old days in Germany! Well, further it has also been claimed that Velocette produced the best 350s… Arguable again, BUT undeniable is the fact that Velocette MAC and K-series bikes are probably the best 350s that I have ever had the pleasure to ride (I’ve never owned a ‘sprung-framed’ 350, only two 500cc MSSs, a ’55 with 250,000 MILES on the clock and a ’56 which I restored from a box of bits). The K-series being the most technologically advanced of the two, does not at all detract from the sheer ease of use, lightness and nimble handling of the MAC, and it’s ease of maintenance and reliability, especially the rigid ones!! Once they shared the sprung frame they became heavier, and so despite improvements in the ‘alloy’ version of the engine put in the later frames, the whole size of the plot increased and made them altogether larger AND heavier. Whatever. MAC? Great ‘little’ bike…

The KSS is altogether different, starting long before in the mid 20s and maturing through the thirties and directly profiting from the KTT racing variants in all sorts of ways… and also, inevitably, gaining in weight as time went on, and more specifically at the change from ‘Mk.I’ (which was never called that while it was in production, of course!) to Mk.II in 1936. Being an overhead-cam design, and a well-developed one at that, meant that for a 350, the bike had ‘spritely’ performance and was very smooth (due to a close-enough to square configuration) . All things being equal, a very comfortable fast tourer (NOT a particularly ‘sporting’ bike, though) capable of eating up the miles with a certain amount of grace and comfort! I always found any Velocette that I have owned almost effortless to ride, I must admit, anyway and the KSS is no exception. My first was one of the last ones made in 1947 with ‘Dowty’ forks (ahem, which was bored and stroked to 490cc…don’t tell anyone!). Of the Dowtys , I can only make the comment that I put them on a par with the Vincent ‘Girdraulics’, which take joint place at the top of the ‘best-forks-I-have-ever-used’ category. No other forks, before or after, handle like they do!! (on British bikes certainly not!)


HOWEVER: the design of the KSS does make it difficult to repair or set up accurately at all without special tools and expertise, which is not always available everywhere and definitely not ‘in the field’. Bush-mechanics have little chance of a ‘get-me-home’ fix if something untoward happens on the road, miles from ‘nowhere’ in particular.

Enter the MSS engine, stage left, to the rescue!!


Same frame, as-good-as-dammit same running gear, but now powered by a pushrod 500. Similar power, but different characteristics entirely. Much longer-legged, loping sort of power-delivery and a much more ‘agricultural’ and very solid design, making repair in the field a lot more feasible and possible.

SO, the bike now looks like this: Both bikes have the same frame and fuel-tank postwar for the Dowtys…


… which I am going to fit (eventually), despite the ‘doom’ cries I hear about losing air just when I don’t need it etc. If well maintained, they are fabulous forks and reliable: Upside-down, air-sprung and oil damped in both directions: Come on, get real! (OK, OK, a set of Girdraulics would be ‘interesting’, but I just don’t happen to have the four to six Grand that would be necessary to obtain a pair! – donations or swaps/buys at reasonable price WILL be considered!!). I might have to settle for Veloce forks off the later bikes for two reasons: Firstly I have to rebuild and then test the Dowtys over a long distance regarding air loss etc and secondly the later forks are perhaps not quite as good, but are more available and don’t have any other reliability issues, being sprung traditionally. I shall be aiming for 18″ rear and 21″ front wheels for tireless long-distance straight ahead work and good low-speed handling as well as reasonable availability of replacement rubber – VERY important. For long-distance off-road work, I’ll need Trials tyres and they don’t make them in a 19″ rear, unfortunately! However, the INITIAL setup will be with Webb forks and the 19″ shouldered ally rim laced on to the 1947 rear hub (without the speedo-drive). Once I swap the forks, I’ll be needing a rear-driven speedo and so will need to change that hub, too, so might as well go for the 18″ rim then… The oil-tank will remain as the froth-towered KSS variant (with an automotive oil-filter) and otherwise I do like the look of narrow guards, but might go the for the wide variants and make up a 21″ front for the sh*tty weather… We’ll see. 8″ headlamp of course, with HID lighting, naturally, a 12Volt rewound dynamo and electronic regulator, gel Battery , BTH manual racing Magneto and off we go! Not much else to it, really ! Oh, a gearbox and clutch will also ‘come in handy’ of course and perhaps a seat…! 🙂

Main thing is to get the bike on the road and start getting everything ‘settled and fettled’ to work trouble-free and without lubrication problems etc. The bike will have to be able to work at considerable minus-temperatures as well, since trips are definitely not limited to the Australian continent!

MSS-Trev-Earl MSS-Trev-Earl2 So the bike will initially look very much like this, except for the 21″ wheel instead of the 19″ front that is fitted here!! The Later addition of telescopic forks will make a ‘subtle’ difference, but this is how it will first go on the road! – Just wondering what the 21″ will look like on the Dowtys and if I will have to make any other changes in concept as a result of potential handling issues… Anyone had any experience of that setup?? Maybe that is a question for the technical forum!

Anyone else have any ideas on general configuration? Would be glad of any comments and tips, experiences and offers of straight-jackets appreciated!

Here, in contrast, the KSS-engined bike, with a bigger front-wheel (21″) and slightly upswept-exhaust (non-standard) but which improves ground-clearance slightly for right-hand-corners. I don’t fancy dismounting and pushing around bends, like the riders of some other makes would seem to have to do… 🙂


I can’t remember where I found the last two pictures, but the MSS ones were from:

My thanks!!


© peter gouws 2013

Made on a mac

Comments Off on Slight Change Of Plans!