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Hello, thanks for coming back about this. so, looking at the pictures, you have left hand gear lever , right hand brake lever. Am I right in seeing that the lever/pivot with the rod end fitted , is on the underside of the crossover shaft when fitted to the frame ? So when you press the brake pedal the lever will push the brake rod backwards ? And therefore push the lever on the brake plate backwards as well ? Which is the opposite way to how the original system works ? (But would still operate the brake, but with the rod in compression, rather than the usual way of the rod in tension when in use) Have I got that right , or completely wrong ? have I misunderstood how it works .

What are the exact requirements for " Vegan Friendly" ? Is it - no leather or fur ? , or is it more complicated ? I was just thinking, some adhesive may contain animal products, that sort of thing. Is the person making them not allowed to eat cream cakes , pork pies etc. ?

I believe the Mikuni is available with recommended jetting for a bultaco from Inmotion , or Allen's performance ? ( I could be out of date on this, as it's a few years since I was looking to do the same) If a Mikuni ( or Dellorto , OKO etc.) Can be purchased with suitable jetting that can save a lot of time experimenting, although some playing around fine tuning is to be expected, in which case the Mikuni may have the edge as there are plenty of aftermarket jets available on eBay etc. Whatever you choose will be an upgrade on an Amal

Hello, could you please post a photo or sketch of how this rear brake rod is set-up & works, as I had a look at doing something similar on my own Ossa , but there didn't seem to be room for a rod ( caused by the brake pedal shaft being in a tight space under the swing arm) I would be interested to see how you got round this problem, or have I missed something obvious that would have worked. I did think of a brake rod that worked in compression rather than in tension, but this is never an ideal way to do things , and would require a strong/heavy rod to avoid bending.

Have you tried Inmotion/bultacouk/Dave renham Marlimar/Steve sell ? Gary warr ? /Ossastuff.com Sorry, can't remember phone numbers, email,website etc. for these people, but search this forum & Google and you should find contact details ( all UK based)

All true and correct I am sure. However if the bike is to be used for some light trials riding, the risk of catastrophic failure is surely quite low. If the application was land speed records or road racing, then Yes, be more cautious and get some spokes that are 100percent correct

If you are using the original chain Tensioner , then that needs to be assembled on to the brake pedal shaft at the same time, and I think this is all easier before the engine is fitted ?

If you have new spokes with slightly different angles , you can often change the angle yourself if you can find a sensible way of holding the end. Have done this myself a few times - it is probably against all the rules of wheel building, but I have never had any problems doing this, and unless you can send back the spokes , they are just being wasted and will sit on a shelf gathering dust.

Only from experience, I would say it does sound like an air leak , which could be a crank seal or cracked inlet manifold (as already mentioned) or a gasket etc. Although that carb may well not be original, if it's been running fine previously with that carb, then you don't necessarily need to change it for an original carb - just find out if it is a fault with the carb that can be repaired - like the missing blanking screw that has been suggested. If it is an air leak you are looking for, it won't be massive, I once had a Yamaha that did the same , and the air leak was so tiny you wouldn't think it could have allowed enough air through to make it rev highly, but it did

I could be wrong, but I seem to remember Guy Martin ( road racer & TV star) doing the pre65 Scottish trial and getting 200+ marks, which was surprising, considering he must have some good skills on a bike. Yet other road racers like Mick Grant have taken up trials very well

Don't think it's been mentioned ( and may not work ?) Could the ignition timing be retarded just slightly to soften the power ? Usually this can be done easily for no cost, and easily reversed if it doesn't work.

I am going to go against the majority here and say a twinshock would be fine as long as you ride it in appropriate trials or sections, and don't expect miracles. As for drum brakes, yes discs are better, but properly maintained drums will lock up the wheels just like a disc. I found the opposite problem - no feel & too easy to lock wheels and fall off when I tried a modern bike with discs , so went back to a twinshock As for for the comment that someone packed up riding in a trial when the drum brakes got wet , in twenty years on a twinshock I have never had wet brakes be that bad , in fact there are twin shocks being ridden through streams etc. every weekend but I have never seen anyone pack up riding due to brakes !

Regarding electric trials bikes, I think electric enthusiasts may be overestimating the demand for electric. Sure, there is a market for them, but perhaps the "old manufacturers" have done some market research and found that at the moment the majority of customers are quite happy with a 2stroke, so why not carry on selling what people want. While still building electric prototypes, if the market changes in the future.

I would take a few measurements first, if the victor engine is 440cc ? It's probably a bit taller than the Suzuki engine. But where there is a will, there is a way

I have used the smooth silver hammerite on a frame and it has been okay, 2K would be better, but to be honest no paint will withstand boots rubbing, scraping over tree roots, rocks etc. So as mentioned, it's a good idea to protect these areas with frame protector/ clear plastic. One advantage of 2K paint is that it is a lot more resistant to petrol so any spilt petrol doesn't wash off your new paint

I seem to remember a time when Horse riding helmets were briefly a fashion with some trials riders, but I expect this was when trials had only recently moved on from flat caps & a cigarette being the required safety equipment.

You can do with out if you like, and I can see why you would want to with the crappy original combined rear brake shaft & tensioner shaft. I have fitted a seperate tensioner to the swinging arm and a guide wheel below the swinging arm pivot, which works better than the original, where tension ranges from too tight when the rear brake is being used, to too loose when the brake is not being used. Have not had the chain come off since changing from the original set up ( which usually happened only at the most dangerous time - like when you were close to the top of a steep climb)

Hello, I think the second picture is of the later "black engine" beamish 250/325, as this had a reed valve intake, as can be seen in picture. The 1975 RL250 is a different engine, ( I think beamish called this the silver engine ?) Unfortunately the picture showing the seal inside the bearing does match what I remember doing I think (could be wrong) the first silver engine is similar to the TM250 and maybe TS250 of the early 1970's, this would be in the first silver engine beamish bikes, the later 250/325 beamish engine was based on the later TS250ER reed valve engine

Yeah, forks were fine, and the engine was running well on the fork oil pre-mix. It was the new/different exhaust smell that alerted me to my silly mistake. At the time I thought I was the only person in the world who had run a 2 stroke on fork oil pre-mix, but later I read a story about Joey Dunlop at the IOM TT. It was said he had run out of fuel while practicing on a 2 stroke bike, a spectator gave him some petrol and he apparently drained one fork leg into the petrol can , gave it a shake , filled the tank and took a steady ride back to pits. No idea how true the story is, but it is the sort of thing I can believe he did.

It's an old air cooled , iron liner engine, not a modern water cooled plated cylinder engine, so its up to you if you want to go as lean as 80/1, 100/1 ( which is fine in modern engines, but maybe a risk in older engines ?) Short term it will probably run okay on just about any oil, at any ratio that has been mentioned, but good oil mixed at a sensible ratio should give the best long term life for engine wear. I once accidentally mixed up fork oil with my petrol ( picked up the wrong silkolene bottle) and rode a trial with no problems before I realised , But I don't recommend it !

I have a similar age Ossa MAR that I use for trials , and have used either 40/1 or 50/1 at different times over the last decade, with a good 2 stroke oil( synthetic or semi synthetic) Doesn't smoke much, and on strip down there was a nice film of oil in the crankcase , which was reassuring to see. You will get varying opinions, anything from 25/1 to 100/1. something like 25/1 may have been the Bultaco recommended ratio when the bike was new and mineral oil was the main option. If it was me, I would be happy using your alpina at 50/1 for trials, and 40/1 for trail riding, light road riding , that sort of thing. The theory is , the more RPM the engine is doing , then the more oil it needs.

It's a while since I rebuilt my silver engine beamish 250, but I seem to remember the right hand crankshaft seal being on the inside of the bearing ( with that bearing lubed by gearbox oil) If my memory is correct, then splitting the cases is the only way to change the right hand seal If I am wrong, I am sure someone will be along soon to say so

If anyone is interested, I did eventually finish this job recently by fitting some betor stanchions I had into the Suzuki sliders. Only problem being the sliders needed reaming on lathe to allow the betor stanchions to fit without sticking. I know there are tolerances & variations, but after measuring several Suzuki forks they all seem to be closer to 1.3/8inch (34.93mm) than 35mm. This is probably silly, but I am wondering if they are actually made to an imperial size? All the other nominally 35mm forks I have, although they vary in size most are close to or just over 35mm.

I have found the original plastic bushes work fine and last well, the most important thing being to make sure there is plenty of decent water proof grease everywhere to cover the steel bolt and other steel parts ,as otherwise the rust that forms is what wears the plastic bushes ( and will do the same to brass bushes or needle bearings)

cmsnl.com have one listed at 121 euros.