This is the last, the 4th in fact, of the early 3-speed gearboxes that I have rebuilt.
This one is from an early Model K and has a very interesting hand shift attached directly to the gearbox rather than the usual petrol tank mounted lever.
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As some of the bracketry and the gear change lever itself is remarkably similar to that found on the later positive stop mechanisms my initial reaction was that this is an early (discarded prototype?) positive stop. However, looking at it a bit closer it is not a positive stop – there is nothing in the mechanism to prevent a 1st to 3rd gear change; it is simply an external gate and fulfils the same function as the GC-3K Gear Control Gate that would have been a factory fitting. Why has it been fitted instead of the production item? I have no idea …like so much else, it is lost in the mists of time.
The one observation that I can make, however, is that quite a bit of effort has gone into making it. I don’t believe that it originated from the Velocette works at Hall Green but it could have been made in the workshop of one of the main Velo dealers, L. Stevens Ltd. in London, to whom the bike was shipped in 1926. In spite of the corrosion on the ferrous components, the gear change turned out to be quite serviceable – many of the nuts/bolts/screws were brass, which helped. Anyway, more about this later.
The gearbox was in remarkably good condition with no bits broken off, good threads throughout and with just the usual wear and tear of the internal components that would be expected after nearly 100 years.
On stripping the gearbox, I was surprised to find that it was fitted with a close ratio gear cluster.
There is a bit of rounding on the teeth of the mainshaft 2nd gear but quite serviceable. The fit of the bush in the sleeve gear was not so good - it was free to rotate, but the wear of the bush on the surface with the mainshaft was quite acceptable and, after aligning the oil holes, a thin coating of Loctite 638 will ensure that the sleeve gear bush never moves again.
The clutch operating lever, C-31/2, that bears on the ¼” diameter thrust pin was not in quite the right place, as evidenced by the witness marks,
and this could only be corrected by removing a small amount of material from deep inside the gearbox shell using a Dremel at the location indicated with a bit of welding rod in the picture below.
The operating lever now bears centrally on the pin.
The layshaft end float was checked in the same way as the other gearboxes (see previous blogs) and a 0.011” shim was added behind the B-22/3 bearing to adjust to 0.008”.
On stripping the gearbox, I found that a 0.080” brass spacer had been placed between the sleeve gear and the bearing
and when I checked the meshing of the sleeve gear and layshaft gear I found that the alignment was perfect. Clearly, someone had taken the trouble to build this gearbox carefully in the past.
All bearings, including the sleeve gear bearing, were renewed - 4 in total. Finally, I found that the B3 cap that screws into the end cover did not quite reach the outer of the bearing that supports the end of the mainshaft resulting in the bearing being not properly clamped. A small annular disc was therefore made to ensure the bearing is locked in place.
Now, back to the external gear shift mechanism. The picture below shows the complete mechanism after removal from the gearbox.
After stripping, grit blasting the larger parts and putting smaller parts in the tumbler overnight, the various components cleaned up well.
It is impossible to get rid of the corrosion but all of the ferrous parts are serviceable and were subsequently chemically blacked before reassembly.
But first, a few observations about this mechanism: first and foremost, it is not a positive stop mechanism. The spring-loaded pawl and cam (the bit with the notches) replicate the functionality of the B64 “gear striking selector” (Velo parts book terminology) and the B66 selector plunger that are located inside the gearbox, shown below.
(note: the above picture is from one of the other gearboxes – the only difference is that this gearbox did not have the notch for neutral)
The second observation is that there are 2 sets of notches. One set has 4 notches – 3 deep and one shallow (and similar to the setup in the above picture) and at the other end are 2 notches for the pawl to engage.
As it was set up, the pawl engaged with the 2-notch end rather than the 4-notch end. Why would that be when there are 3 gears and a neutral? The semi-circular cam part could be fitted either way round and so the only way to find out was to try the 4-notch end.
The reason immediately became apparent: the notch for 2nd gear had been put in the wrong place! By checking the distance (to ensure it is the same) between the B65 striking lever and the point of connection of the linkage on this mechanism in each gear I found that 1st, 3rd and neutral were correct whereas the notch for 2nd gear should have been in the position indicated by the mark that I engraved on the cam shown below.
Whoever made it assumed that the notch positions for 1st, 2nd and 3rd would be equidistant – they are not. Rather than make another cam, they simply swapped it around, made 2 notches for 1st and 2nd and 3rd would be selected without a notch – this works fine – I’ve tried it.
If I can find a spare day or two, I’ll make another cam with 4 notches and try and get them all in the correct places.
In the meantime, the gearbox and the shift mechanism are all reassembled and working well. The gear indexer may not be pretty but it is an original period feature, probably made 95 years ago, and is part of the provenance of this bike.
I’ll make a new ¼” threaded adjuster rod and refit the kickstart in the next day or so.
And Finally….
Somebody asked me recently what was my first motorbike. Well, the first motorbike that I rode legally on the road at the age of 16, back in 1967, was an AJS Model 20 with a Swallow single-seat sports sidecar. The AJS Model 20 is a 500cc twin. In those days, the law allowed learners to ride solo motorcycles up to 250cc and unlimited (!!) capacity if a sidecar was fitted. I went for the 2nd option. Life was much simpler then: a new rider applied for a provisional driving licence, bought insurance and off you went on the steed of your choice – without any training whatsoever.
By the way, please don’t think that this bike was in any way exotic. I bought it from a mate for 5 GBP and it subsequently needed a lot of work to make it roadworthy. I had also never ridden a bike + sidecar before and anyone that has previously ridden only solo motorcycles gets the shock of their life the first time they ride a combo! As you quickly find out, you have to steer them and point them where you want to go rather than leaning.
Anyway, in those days I lived in Shanklin in the Isle of Wight and on the day of my 16th birthday I set off from the farm from where I had bought the bike to a motorcycle dealer in Carisbrooke by the name of Dave Death to get an MOT. They are still in business now – see their website here. If you scroll down their web page you will see a picture from 1962 – this is exactly how it looked when I went there.
The bike failed it’s MOT test on pretty well everything and so I set off for home – it’s about 10 miles - to start repairing things. About half way home, just coming into a village called Godshill, I was approaching a left hand corner and blipped the throttle to change down a gear and ….the throttle stuck wide open. There is nothing worse than an engine revving it’s nuts off under zero load – there was no kill button and the only thing to do was to keep it in gear and try and slow it down. Anyone that has ridden a sidecar outfit knows only too well the consequence of too much speed in a left-hand corner: either the sidecar wheel comes off the ground (as a prelude to turning over) or you straighten up, keep the sidecar wheel on the ground and go straight on. I choose the latter and went straight through a hedge on the opposite side of the road, ending up in the middle of a vegetable patch of somebody’s garden ….with the engine still revving. I managed to stop the engine by removing the spark plug caps and simultaneously electrocuting myself. But at least the engine was now quiet. After a bit of work, I nursed it home. An interesting first day on the road.
However, this wasn’t my first ever 2-wheeled + engine “thing”; that was a Velo Solex. For anyone that doesn’t know what these are they look like this.
These were produced in prodigious quantities in France immediately after WW2 and consist of a 49cc engine that has a friction drive onto the front tyre. The engine pivots and so can be ridden as a cycle. It is started with the engine lowered, pulling in a decompressor lever with the left hand, pedalling like hell, letting the decompressor lever go ….and away you go. There was no throttle – either the engine is under power or it’s not.
So, how did I come by one of these? Well, back in secondary school days it was customary for boys (I have no idea what girls did – I had zero interest in girls at the age of 13) to get a job during the school summer holidays. I had a variety of jobs during my school years – gardening, clearing tables and washing up for a tearoom, making plastic bags in a factory, working in a garage but the first job that I had, for 3 summers in fact, was working at a shop by the name of Barney’s Emporium in Shanklin.
This is a picture of it in its heyday.
Acknowledgement to whoever owns the copyright of this picture
The shop was interesting, to say the least; it was owned and “managed” by Barney Powell and the part of the business that made any money was selling binoculars and telescopes. The other part of the business was a joke shop and the shop window was full of Barneys own jokes and comical take on life and which raised money for charity which was donated to the local Cottage Hospital each year as I recall.
Barney came from a family of actors/musicians/comedians and Barney himself was a comedian and musician that, among other things, played the xylophone on stage with his feet while sitting on a high stool! Quite a character.
But back to motorised bicycles…. Barney had a Velo Solex and for the 3 years that I worked for him he asked me to take it to a garage in a nearby town for an MOT test. I was supposed to pedal it there but, needless to say, once I had gone past the local police station in Shanklin I lowered the engine onto the tyre and experienced the pleasure of power for the first time. I remember when I got back (having passed the MOT) Barney feeling the cylinder with his hand and, with a glint in his eye, commenting on how hot the sun was today.
It turned out that this was his second Velo Solex. He had given an older one to a previous employee that had since started work as an engineering apprentice but had no interest in, and had done nothing with, the bike. I acquired it (for nothing) and then started to figure out how to get it to go. The engine on these bikes has a small petrol tank on the right side and a flywheel magneto/lighting coils on the left. After fiddling around, not really knowing what I was doing, I managed to get it going.
In the meantime, I had spotted another little bike with an engine in my neighbours open shed in their back garden. It had been there quite a few years, quietly rotting away, and I got this one too. It was a Cyclemaster – one of these.
I managed to get this going – so now I had 2! And what do you do when you have 2? You race them. There were always plenty of quiet lanes and footpaths where my buddy and I could ride these – we were still some years away from 16 years of age - we’d end up in some kind of social care these days. But it was pretty harmless and we learned a lot.
So which bike won? The Velo Solex. Although I didn’t know this at the time, the Cyclemaster was produced in 2 engine sizes: initially 25.7cc which was increased to 32.6cc in 1952. Although mine had the larger engine it could barely power a skinny lad along a straight – it was one of the noisiest and definitely the most gutless bike I’ve ever ridden.
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