2stroke4stroke

Are you sure the roller was not missing before you started stripping the motor?

Original sizes were 2.75 x 21 and 4.00 x 18. 120/100 might fit but would not comply with ACU regulations which require 100/100 section with further constraints on tread pattern. See TSR 8.

According to the commentator it's a Yamaha, certainly looks like it, they've been mentioned/pictured on TC before.

Unobtanium = whatever price the market will stand. With the prices I have seen other motorcycle engines fetch, 500 to fix an unusable motor does not seem beyond what many would be prepared to pay.

As long as we don't call it "racing".

If you ride ACU then you can have short term third party cover for trials through the ACU. No idea what the cost is though but it may open up options for third party cover to get bike taxed etc.

You have a point there.

Yeah, I always have to dab on a left hand turn.

A lesson learned? It's standard practice for the experienced rider to grease every thread it's possible to get at when buying a bike, new or used.

Doesn't matter what you call it Allan, the ignorant will still get things mixed up, just as you illustrate. I had a chap at work who, having seen my bike, kept asking if I was still doing the speedway.

Hey, at least you stiil have a local hardware store - they've gone, by and large, in the UK to be replaced by big sheds that don't have much of what we want and only packets of "thousands" when they have.

Used on works Bultacos in the day.

Definitely Magura levers, high quality, but use them now and you find the leverage is wrong though we were accustomed to a heavy clutch back then. Still have a set unused which I suspect will end up in a museum.

No need for a security bolt - the air does not know it is in a tube (which conforms to the internal shape of the tyre and rim) and exerts the same pressure on the carcass as it would without the tube. If the tyre grips the rim tubeless then it will grip just as well with a tube if correctly seated. I ran a Beta for long enough with a tube and there was no creep. Clearly a tube could pinch puncture more easily than a tubeless tyre but, in reality, it does not seem to be a problem. I've never tried the experiment but if a tube so punctured within a slow leaking tubeless tyre would not you just end up with a slow leaking tubeless tyre with an empty tube in it as the tyre would retain the released air? However, I'm prepared to believe that a small handful of riders from the world of trials could, in a blind test, tell if a tubeless tyre had a tube in it from the performance viewpoint. They all have technicians to sort leaky rims though.

Under Newton's Third Law it makes no difference to the action of the spring but it is normal to put the tighter coils to the top to reduce unsprung weight (slightly).

Surely the stanchions should have been plated to match the dimensions of the bearing surfaces? Did the plater not ask what diameter was required?

The original frame numbers on RL 250s were just a dymo tape. I doubt whether a number you chose to use could be challenged with evidence that it was not correct.

Interesting what you say about punch. A chap local to me is now on his fourth Beta 4t, all kept standard. He gets very good results but seldom seems to go above a fast tickover.

Quite, but we seem to be struggling to get worthwhile numbers of riders to do WTC whereas the SSDT gets about 50% (or is it more?) entries than it can accept,

As Scottie said, "Ye cannae beat the laws o' physics". In order to go backwards first you have to stop. He definitely went backwards.

The greatest virtue of the Beta is its silence, if only I could get the 4RT as quiet. Don't spoil it - you clearly don't need any perceived performance improvement.

Chances are that it was registered at the time - you may be able to recover the number.

No, but as you obviously don't want to rob capacity from your battery I suggest using a mountain bike light. Good performers can be obtained at prices ranging from very reasonable to totally absurd.

As your forks won't know left from right they will probably respond to all three of Newton's laws of motion as before, all else being equal.

Have a look at some old SSDT results to see how well a TY 175 could fare, particularly in the hands of Peter Oakley. They were winning awards all over the country at many levels. Even beating Montesas☺, especially when I was piloting the 348.