woody

When you say all the proper Vesty mods, do you mean it was one of the 40 or so bikes that had the swingarm conversion to move the pivot a bit closer to the final drive - based upon the early experiments? Or a copy of Vesty's last bike. This had some pretty big alterations all round and I didn't know they did any replicas of that - engine mounts moved to tilt engine, bashplate reshaped because of engine position, hybrid exhaust, airbox etc.

No, haven't got a contact number or email for him - do you have one? Just managed to source a decent selector shaft from ebay USA though.

Here's a question for those who understand port timing - which I don't Having a few problems with gear selection set up on my '75 310 MAR. Under the bench is another 310 engine I picked up about 25 years ago. It's a later engine from a green bike. I stripped it to compare selector mechanism and set up but whilst apart I thought I'd compare porting as I'd heard that the later bikes were different. On the 75 bike, the inlet port measures 25mm top to bottom and is 25mm high in the barrel (from bottom of liner to bottom of port) On the 79 bike, the inlet port measures 20mm top to bottom and is 30mm high in the barrel On the 79 bike the port is also narrower in width but I couldn't measure by how much. So basically, smaller size all round and higher in the barrel meaning it opens later. On both bikes, the distance from the top of the port to the top of the liner is the same. Both use the same piston. Exhaust port and transfers all appear the same. So the question is, what does this mean and how does it translate to engine performance? Just curious as I'd heard that the later bikes were sharper than the earlier lazier bikes. The later engine has been fitted with a huge counter weight on the clutch in place of the cush drive. It's a home done job but very neat but it weighs nearly as much as an ignition flywheel which suggests someone was trying to calm it down - why I've no idea as they were hardly 350 Bultaco / Montesa power. Finally, anyone any idea of sources for gear selector shafts and return springs - I'm running out of useable items trying to sort this gearbox.

Nice comeback - seems he's on the British humour wavelength Eddie Lejeune could ride either no-stop or stop and hop as sections demanded. The trick riding started long before Tarres and his Beta. Riders were stopping, hopping, reversing on twinshocks. The advent of monos just made it easier and riders like Tarres moved it on a level

One of John Reynolds' Bultacos? One of those has been up for sale on ebay a few times recently. Dave Renham will be able to tell you if it was a bike modded by Commerfords for one of their supported riders.

The Twinshockshop do a set of yokes for the TY Mono with repositioned bar mounting which look as though you can also use risers with http://www.thetwinshockshop.co.uk/parts.php Just scroll down the page and you'll come to them

Not a lot of experience no, a mate has one which I've had a few rides on and it has a nice feel to the chassis. Impressive for a 1968 bike. But... the picture you've posted doesn't look like his and the tank with Cheetah on it is too big for something that would have been fitted to a trials bike. Footrests don't look right either. Obviously the picture doesn't show all of the bike so difficult to tell, but I'm not sure it's a Cheetah See if you can get some pictures of both sides and with the tank and seat off. I think Westyfield has a Cheetah so I guess he could tell you for sure

Chassis number should be stamped on the headstock. Is the frame chrome? They were all chrome as far as I know You don't need the engine number to apply for the V5 - The V62 form you use only asks for the chassis number I think. Plus £25 fee.

When you say no V5, do you mean it has a registration number but you haven't got the log book or that it has never been registered at all and you want to register it? Two completely different processes First one is easy, just complete a V62 which you can download off DVLA website and send it to them with £25 fee. They'll write to the last recorded owner for confirmation but if they get no reply within 2 weeks they issue you with the V5 anyway To register it, you first have to get it (more accurately, the chassis number) recorded on the NOVA database with HMRC as without it being recorded on there DVLA won't issue a registration number for it. Recording it on NOVA tells DVLA that no VAT is due on the vehicle. DVLA now check the NOVA database on every V55/5 registration application they get. If the vehicle isn't recorded on NOVA they send them back to the applicant.

The Cheetah is a nice bike to ride with a more modern feel than you'd expect from a late 60s bike. Chassis is stable and it turns well without having any nasty traits that need 'modernising'. It feels comfortable riding either non-stop or stop/go balancing using the clutch/brakes. Footrest position is high but footrest positioning is personal preference anyway. Villiers 250 is a good engine but there are so many variants... In 'normal' or 'proper' trials trim they're more than adequate for classic trials or B route in modern trials. Things like suspension and brakes are going to depend on what's fitted but with decent units, no geometry changes are necessary to make them work well (my opinion only, obviously, but based upon having ridden one) I've had no problem with old fibreglass tanks using Shell V-power and that includes leaving the fuel in it and not draining. Obviously, some other petrol brands aren't so kind on them. I'll ask someone who has one about the chassis number. Villiers engine numbers are a different matter and it's probably best to speak to Simon at Nametab if no-one on here can help

NOVA only came to being in April this year, so if your Honda was imported in the last couple of years it's doubtful it's going to be on that database, so be prepared to get your application back as requiring NOVA approval. One day, DVLA might grasp how this process is supposed to work and the real reason it was introduced. Until then, we're probably all going to suffer when trying to do things properly in getting old bikes road legal Shame about the Experts, always look forward to and enjoy that event.

Have you had your bike recorded on the NOVA database with HMRC? DVLA will no longer registter an old vehicle that's been imported (ie: anything that wasn't of UK manufacture) without it being recorded on NOVA to confirm no VAT is due. It doesn't mention this anywhere on their website for registering old vehicles on an age related plate but it is a pre-requisite now with no exception I took my V55/5 into the local DVLA office on August 3rd, they checked the paperwork, confirmed it in order and sent the forms to Swansea saying I'd have the registration in about 10 days. They confirmed what I believed, that NOVA wasn't required as the bikes had been in the UK for 30 - 40 years and VAT would have been paid when they were imported. Two of them were too old for VAT anyway... Nearly 3 weeks later I got the paperwork back, rejected because my bikes weren't recorded on NOVA with HMRC. I sent the necessary forms to HMRC - you can do it online or manually by post. I defy anyone to be able to complete them online as they aren't appropriate for old vehicles with the information they require - even HMRC staff couldn't complete it online for me with me reading out the bike details, bike age, date brought into the UK, name of seller etc. The NOVA recording is supposed to be for vehicles brought into the UK independently from April this year to prove VAT has been paid. DVLA don;t seem to understand this and want EVERY application to be recorded on NOVA first. It's nothing to do with HMRC, it's DVLA not being able to apply their own rules properly. If you can complete NOVA online, your vehicle goes onto the database immediately. If you apply by post it takes about 3 weeks turnaround. Mine were eventually put on NOVA and I sent my V/55 applications back to Swansea over a week ago. I'm now hoping they will be registered. I'm waiting to either get tax discs in the post or the applications returned for another missing requirement with the documentation. Nearly 2 months so far for what used to take a matter of hours at the local DVLA office....

From the engines I've worked on over the years the gear cog goes the way it is shown in your photo at the start of the topic. Thanks for the offer re: the parts list but now I know the shim should be there I'll know to look out for it when I get around to stripping the 198a. Everything else is normal Sherpa.

ok, thanks for that, explains why I've never seen one in engines I've worked on. I have a 198a to rebuild so at least I won't be wondering what that shim is doing there when I get around to doing it. Can't recall my 199b having one though

So is that a parts book specifically for the 198/199a? It's not in any of the parts diagrams in manuals I have, or any engine I've ever taken apart, but as I mentioned before, I've never had an 'a' model engine apart

The clunk should be the bottom left side of the slide hitting the throttle slide height adjustment screw (throttle stop screw) This is the angled screw you can see on the left side of the carb next to the air screw which is horizontal. It's used to set the tickover by lifting the slide slightly and allowing air through the carb which draws fuel though the pilot jet. The fact that the slide is hitting something when it returns suggests that the cable is the correct length as if it was too short there would be no noise when the slide returned. Whilst you have the carb off, unscrew the stop screw and you should see the slide eventually close to prove it has full adjustment. Count the number of turns you unscrew it, then you can put it back in the same position when you refit it to the bike. If the engine races when you start it, just turn the screw out until you get the tickover speed you want

No idea, never seen any

Turn it around and look through the front of the carb and see if the slide is shut. Difficult to tell from the picture angle but it looks fine

What's the spacer sitting on the end of the mainshaft in the last but one picture? I've never seen one of those in any Bultaco I've had apart. The only spacer on a 5 speed model I've ever seen is on the kickstart shaft, although I've never had a 198 apart. Never seen one on a parts diagram either. Only the 340 has a spacer on the end of a gear shaft as far as I know and that's on the layshaft. Do the crankcases bolt together and the shafts turn with that spacer fitted?

The rear of the slide has a D shaped cut out so even when the slide is fully closed, it may appear as though it is 'open'. It isn't as the front of the slide is flat at the bottom and when closed it sits flush with the bottom of the carb and stops airflow. There are slides with different size cut-outs to vary the airflow - are you sure it isn't this you are looking at? If the slide is raised 10mm in the carb body and you can see underneath it through the carb, then either the throttle cable is incorrectly adjusted or too short, or, the slide is stuck open in the carb body.

Yes, it unscrews. They can get tight so it's just a case or working it free. If you can't do it by hand use grips to get extra leverage but don't grip it too tight or it will crack If it does break, new ones are available

Somewhere around 1973 the gearbox mainshaft diameter changed where it sits in the clutch side bearing, therefore so too did the bearing size. Can't be any more specific than that though, sorry, no idea if there is a specific model number this occured from. Crank bearings and seals are all the same size Clutch hubs and baskets differ, as does the spacer the hub sits up against Later gear selectors forks are thicker than early ones and won't fit early gears Bultaco UK is your obvious source for this info

The tank seat unit isn't a recognised Bultaco one. But, I had a basket case model 92 a few years ago which came with an identical tank to yours (sold the bike on) Yours is the only other one I've seen. I'd assumed mine had been adapted from another bike to fit but no idea what. It's very similar to a Honda Seeley but they are just a shelter that fit over an alloy tank. Mine was all fibreglass. Maybe someone was making aftermarket tank units for Sherpas that have long been forgotten about. Whatever it is, they fit the Sherpa pretty well. The boomerang silencer was fitted to bikes around 1974 so it's fine for your bike if you're bothered about period fitments. The bike is in original condition apart from the tank and mudguards.

Steve, kickstart assembly is how it is because the cases are split and the ratchet gear has moved on the shaft, it's no longer seated behind the stop. Neutral is easy to find without the manual, although I agree, working with the manual is far better. Only takes a bit of logical thought to position the drum correctly

From memory I don't know but look at it logically. If that's how they came out then they are the right way around as if they weren't you would only have had 3 gears.... Look at the selectors, there is only one that can be fitted the wrong way around for them to fit back into the gearbox, the one furthest away. If you turn the other two around their pins won't fit into the selector drum when the fork is located on the gear.