Hi, just brought a spare engine from a UK breaker who'd totally forgotten where it came from. It's not got an engine number, just 4GY stamped on the boss, doesn't appear to have been messed with and no sign that the cases have been replaced unless it was a very long time ago (also unlikely at £2K+ a set!). I think this makes it an import from outside Europe. It has a 6 plate clutch and digital speedo pick-up normally seen on purple frame bikes but has clearly been in a blue frame as the evidence is still on the mounting bosses, no sign of earlier purple underneath. So I seem to have an earlier engine that was fitted to a later frame. Obviously it will serve it's purpose for me with no great problems but I'm intrigued and can't find anything on here or ttr250.com FAQ to explain it. Anyone know how this may have come about? Was this actually a mix used abroad somewhere as std from Yamaha?
split year in 2000 that had that mix of engine and frame, or maybe as you said, someone put an older engine in newer frame. the mystery begins............
Ps all bikes into the UK apart from 2004 are imports
4GY is all you will get on the white metal-tanked TTR crankcases.
I recall being confused when I saw a photo of blue TTR with purple wheels but I can't find it now. It was a genuine original not-mucked-around-with TTR250 manufactured in 1999 which was close to the 2000 change-over year quoted by Steve.
My guess is that you will already have spotted the differences between the 4GY and 4PX engines