feetupfun

If your inner bush is worn or pitted, it will not work well with rollers

If you can get a properly hardened inner bush for the rollers to run on that that kit would probably be OK. I bought a similar kit to the one in you link a few years ago and fitted it along with a new (aftermarket) inner bush, but with only a little use, the rollers wore through what turned out to be very thin surface hardening. I think they would be fine with a new, genuine Yamaha inner bush The standard TY175/250 plastic bushings fit a very wide range of Yamaha models

re P.S. Yes. Go into your account then "settings" then "other settings"

Yes you can wrap it. You would not be the first. The negatives are corrosion, weight and appearance

It's so variable depending on the sort of riding in the three hours, but if that figure is for riding in a competition trial with a short loop and queues at most sections then it sound about right.

All the modern ones have small tanks standard but there are auxiliary tanks available (called long ride kit) that fit in the dip and have a bum rest on top. Standard tanks on some modern bikes need to be topped up during a one day trial. If your knees are really crook there are electric start kits available for some brands. There are proper electric trials bikes that run for ages on a charge and are great for stealth riding. Of course twinshocks have a huge fuel range and can be ridden sitting down and are very low maintenance. Bultaco and Montesa twinshocks can be very quiet. TLR200 Honda is exceptionally good for doing what you've described.

Crankcase cover - which side? which TY250? Kickstart - which TY250? Where in the world? New? Second hand? Genuine? Aftermarket?

Lean the bike over and if there's a ball it will probably slide out. If it doesn't come out using gravity, take the clutch pressure plate off, remove the mushroom and push the ball out from either end.

320mm to 340mm will work. Top mount position depends on what shock length you want to use and what the shaft travel of the shock is and how high you want the rear end

Very common mod to increase rear wheel travel and if you use the same shocks, raise the rear. Was standard on Yamaha frame Majesty 175/200. Lots of TY175s modified that way by owners in the 1970s and still commonly seen being done. There was a kit available for it a few years ago.

Measuring the peak pressure on a two stroke will always give variable results. Without changing anything else, the amount of oil at the ring/bore interface at the time of the test will make a significant difference to the result. Fitting new rings without honing the bore will make the results of that sort of test even more variable.

Somewhere within a very wide range depending how well the restoration was done

I wouldn't assume anything about a fuel tap

What's a side casting?

Hidrol was/is a brand of fork oil and the 7 means 7 WT

It's a fairly normal thing to shift to neutral before you come to rest if you want to then sit in neutral with the motor running. It will shift easily to neutral if you shift when there is no torque on the gearbox (ie motor not driving bike or bike not driving motor). It is quite normal for shifting to neutral to be difficult with bike stopped and motor running (clutch drag puts torque on the gearbox).

I suspect that the single piece WES design may have been improved at some point in time regarding how noisy it is, because mine does not sound like how you have described yours. I bought mine maybe three years ago through TYoffroad

Yes. I suggest you put your new thread in the forum for the brand of bike you are working on. If it's a Beta there's a few novels worth of reading about clutch drag there already.

The sealant is usually low viscosity epoxy resin. There is a commercial kit that also contains cleaning agents that is popular (Caswells)

Yes that is standard on Shercos. Initially (in 1999) Shercos came with open main bearings and they didn't have a long service life. It was found that sealed bearings lasted longer. Main bearing ventilation/lubrication ports that existed on many two strokes previously, was lost in pursuit of a narrower engine when the Sherco trials motor was designed.

The original 348 seat is made of a foam core with a sewn black vinyl cover and has a very similar shape to the odd-coloured seat in baz348's photo. After the 348, Montesa went to using naked black rubber seats on their trials bikes.

As well as the suspension linkages, I can recommend you also service the swingarm pivot and steering head bearings. I hope you get to them in time before corrosion occurs. I bought a one year old bike a while back and found that all the rolling element chassis bearings had corrosion happening due to lack of any protective lubricant being applied when originally assembled. It seems that very little attention is given to lubing those parts during assembly on some new bikes. Sealed wheel bearings at least are usually greased by the bearing manufacturer and last longer before failing.

Nice 348 What is it about the seat that causes you to say it looks original?

Probably repairable, but welding up hubs is something that is an (expensive) last resort on rare bikes that you can't get replacement parts for. Front TY hubs are still being made and if you have a decent look on eBay you will probably find new hubs available ex Thailand. Apart from that there will be plenty of second hand TY front hubs available. I'll sell you one if you are stuck. It's quite rare to break a front hub. I'm interested in how it was achieved.

Sounds like you are asking about the WES TY175 systems. If you have a standard front section and replace the end muffler of the competition model TY175 (525) exhaust with a WES end muffler, the exhaust note will be a lot quieter and will no longer sound raspy, irritating and machine-gunnish. If your TY175 end muffler is the type fitted to the TY175 and TY125 that had to meet strict noise limits for road use (TY175JE and TY175JC and TY125), the WES end muffler will make it slightly more noisy. The one piece WES TY175 system is slightly more noisy than the WES two piece TY175 system. Both would be considered acceptable at a competition event as far as noise level goes. Yes the WES systems are different internally to the original designs and in my experience, enhance engine performance compared to the standard exhaust. The biggest bang-for-the-buck for performance and noise reduction comes from fitting a WES end muffler. Replacing the main section with a WES provides a good bang-for-the-buck handling improvement (weight reduction). Be warned that if you are planning to use a WES exhaust system and ride your TY175 at sustained high speed, you are at risk of the exhaust system catching on fire. They are intended for use in trials competition.