Q: I’ve just been out and bought myself a very nice looking Honda NSR250R road legal race bike. I got it at a good price but it does have a misfire problem.
When I pull off the bike starts to misfire and judder until the revs rise and then it seems to clear out.
I’ve fitted new plugs but they’ve made no difference and I have to slip the clutch, a lot, to drive through it, so I’m worried I might wear it out.
I’m looking forward to hearing your reply because I like the bike and want to stay with it?
El Presidente
A: Well ‘Mr. President’ I wonder how many kilometers the bike has covered because high-mileage NSRs can develop all sorts of problems?
So it could easily be a multitude of problems like the crankcase seals for example. There’s also a ‘labyrinth’ seal that separates the two con-rods. If worn this will cause the motor to ‘steal’ air/fuel from one side to the other. Or perhaps the carb’ slides are badly worn, which is common on oldish two-strokes. And the list goes on.
Either way it sounds like the engine is heading for a major overall and lots of fresh new parts, which might become hard to find? Good luck.
