You appear to have AJS or Matchless lower fork legs with more modern fork internals with a made up distance piece to fix them together. This is how they are normally made up irrespective of which forks are adapted.
Your best option is dismantle the forks remove the oil seals and measure both seals and the space they fit in to get the best replacements.
Like Woody I had a troublesome Motoplat stator with symptoms similar to those you describe repaired by Bradford Ignitions and its continued to work well ever since. Steve Sell produces a full replacement ignition system for the OSSA should you need to go there. Electronic systems seem to be perfect just fit and forget until its troublesome then sometimes you think its anything but the ignition.
The Beta Rev 3 200 has a rear sprocket one tooth bigger than the 250 making it slightly lower geared. Check what you have fitted before buying one but from memory the 250 has a 40T the 200 a 41T. Changing the rear wheel sprocket does make a worthwhile difference along with a slow throttle and retaining the flywheel weight on the 250. The 200 I'm familiar with did not have the extra weight when new. With the carb nicely set up you should be okay. A reduction of one tooth on the gearbox sprocket equates to adding around four to the rear which would be much lower.
Best practice is to always warm the hub around the bearing using a heat gun to expand it so that the bearing releases easily and the new one pushes fully in with similar ease.
If you drive the bearing out without first heating the bearing housing it will likely remove some of the surface by dragging out material where the bearing sits then the new bearing will not be held firmly requiring bearing fit to hold it in place. Sometimes the hub can be ruined by driving the bearing out when cold.
To refit the new bearings press in gently while the hub is still warm using a socket whose OD is similar but slightly smaller than the bearings outer diameter, NEVER press on the inner bearing race when replacing only the outer.
Ttspud as I said previously you're most welcome to come along to the classic trials in this area in which I ride. Bring your bike and I'm sure you would have an enjoyable days sport and most likely make some new friends at the same time. At least then you would be getting some enjoyment from trials which clearly you are not at the moment.
I would be interested to know just what bikes people were using back in the day as I asked in my question to you, please answer that.
I installed a grease nipple to the pivot tube on my Model 124 then its easy to keep it greased without having to dismantle it but obviously it would be best to remove it now to ensure everything is okay.
Yes I agree with b40rt that should be the best course of action. You could also disconnect the source wires from the HT coil so that there is no spark at the plug.
Never use washing up liquid or silicone sealant as both contain salts and will corrode the rim. If its already damaged by corrosion remove the valve stem from the rim band and fit a tube.
Treat the forks the same as any others and don't worry about the air valves. With the leg out of the yokes undo the top nut using a hexagon socket if possible so as not to mark or damage the alloy top nut keeping some downward pressure on the nut to counteract the spring tension, then you'll need something like a long flat bladed screwdriver down the chrome tube to engage with the slot on the damper at the bottom then you can undo the Allen bolt from under the slider. The slider will then come off the chrome tube you will then be able to see the circlip to remove the internal fittings. Just lay everything out in the order it came out and again take a photo.
Dynasurf or Philpotts are the go to place's for a re-chrome.
I would work on one part at a time just a clean up and service, don't have to many things on the go at once. Photograph everything and try to replace only what is really needed. Do you have a photo of the damaged rear wheel. It's a while away but the show at Telford in February is the place to get everything you need if it can go ahead.
Hi triasrfun, I have a 159 sherpa, I had a carb built to your above spec and bike runs spot on,,,, I have a 78 350 too, rebuilt to 340 cc, carb is lean on bottem end with these settings, shall I just richen it up with bigger pilot jet, or does this bike need all different settings, ps is Bob on on power, thanks
Pleased to learn your bike also runs well with the settings I use on my own Bultaco.
I would initially go up to 30 on the pilot and then maybe lift the needle by one ring if you think it needs it, the settings above should not be a mile out on your 350 they work well on my 199A.
The Greeves Challenger is a scrambles/moto-x bike fitted with a small diameter Stefa ignition, very well suited to what it was intended for but unsuited to trials use. The Challenger cylinder and head with slight variation were used on the TFS, TGS, THS and TJS Greeves trials bikes.
The head angle on the Greeves alloy I beam didn't really change but the make up of the fork yokes on the leading link forks certainly did to change the steering angle.
John Banks is best known as a world championship moto cross rider for BSA though I understand that earlier in his riding career he rode a DOT.
Looking at the main frame loop and lower subframe on your bike the design is very similar to a DOT though the DOT bikes made around that time used square tube for the main frame loop.
Can now confirm the that this frame is a Villiers engine Burian built by John Banks BSA works rider in 1965, it was confirmed by Trevor Andrews who owned the bike in the early 70s and spoke to John this evening and he told me some history .
The hubs are early Husqvarna and engine was Villiers with Challenger barrell.
Doug Theobald road a bantam engined Burian and there is a photo of him on the bike in this forum by Deryk Wylde
So it looks to be a rare bike not many made and I don't know if there are any around ( I'm sure there must be )
On 4/1/2021 at 12:25 PM, trialsrfun said:
Hi Greevesman,
Well hopefully someone may yet come forward with details of the frame maker but either way you have an interesting bike that is well worth restoring.
If you do not have a cylinder head one from any of the aftermarket alloy cylinders can be fitted as the stud spacing is the same for all of them
Forks appear to be Ceriani rear hub possibly Triumph Cub but its difficult to tell from the photos which do not really show it, wild guess for the front hub which is barely visible Husqvarna???
Mudguard stay is very similar to the Greeves one fitted to some Anglian models with Ceriani forks or the Greeves alloy beam MX models as well as the Griffon.
If it were my bike I would do a rolling rebuild just clean and tidy everything and up take the motor to one of the above for a rebore as well as all the bits needed.
Pleased that you have found the make of your bike also that I correctly identified both the front hub and cylinder. Hope you restore and ride it, be good if you can post pictures here on tc of the finished machine.
If you do not have a cylinder head one from any of the aftermarket alloy cylinders can be fitted as the stud spacing is the same for all of them
Forks appear to be Ceriani rear hub possibly Triumph Cub but its difficult to tell from the photos which do not really show it, wild guess for the front hub which is barely visible Husqvarna???
Mudguard stay is very similar to the Greeves one fitted to some Anglian models with Ceriani forks or the Greeves alloy beam MX models as well as the Griffon.
If it were my bike I would do a rolling rebuild just clean and tidy everything and up take the motor to one of the above for a rebore as well as all the bits needed.
greevesman is this the bike the cylinder came from that you are asking about here on TC? If it is post a photo of all the parts together including tank and exhaust, bit more to go on then. Interesting looking frame though.
Which Carburettor
in Classic Trials
Posted
I had a Mikuni for my Bultaco from Motocarb Motocarb - Home not sure if genuine OKO are still available.