tobster

Any other suggestions anyone? Thanks. Get a noisy exhaust and you'll never hear the rattle?

xj is a four cyclinder engine, whereas xs is 2 cyclinder - that should narrow it down (assuming you can count )

hi unfortunately ty250 are never very valuable (not in the UK anyway, though clearly depends on your interpretation of valuable), say £500 maximum, even less so if they're tatty. So if you're going to sell it anyway, it hardly seem worth stripping it down to paint the frame etc. Why not finish the build, ride it for a year or so i.e. get some pleasure out of it, then sell it?

hi imports are often less valuable/desirable than the home version also AND insurance companies like to know too. I'm sure if you phone/write to Yamaha UK (rather than your local dealer) they will be able to tell you whether there are any major differences between the US & UK specs. Good luck

it ought to make absolutely no difference, except of course costing you more money. If it was that easy to make an engine perform better then we would all be using optimax, tesco99 etc . The vast majority of engines are designed to run on unleaded. Until you start tuning it, unleaded is perfectly adequate.

there is no primary chain in there to rattle. it must be something else. could it be gearbox sprocket?