does any one have a copy of a manual for a ty 250 mono if any one could help i will be most greatfull

There's a ty350 one here; http://northover.com/Bike/YamahaTYManual.htm. I'd imagine a lot of it will be the same as the 250 bar maybe the timing, barrel and piston details etc but I'm no expert.

Several sources including John Cane of TY Trials http://www.tytrials.co.uk/ used to do a CD for the 250 monos, they seem to have dried up for some reason, maybe a copyright issue. Might be worth calling him, might have an old copy propping up the office desk...