Okay I have a few questions on the 1990 250 engine I am hoping someone can advise on. The engine I have is going to get a complete overhaul and in the process tuned specifically for woods use.
I want to bore up this engine as big as possible/practical also.
First big question is that I would like to replace the tired old crank and rod with a hotrods crank. I see they advertise the 92' onwards cranks with 2mm longer stroke than the 90 engine which would suit what I am doing as long as the crank will work with only stroke adjustments needed.
Second the cylinder I have has been sleeved. The cylinder was bored under 74mm to fit the sleeve, so I am wondering if this year cylinder can be bored and plated to 74mm and made to work with the power valves used in this year?
Any advise most welcome.