I have a 2002 TRX 250EX which has been running well for the year I have had it. My son said it was running hot and then it died. Will not start now. Cranks over well, and seems to have a strong spark. Carburetor checks out OK, actually cleaner than I expected. Plug wire was pulled out of boot, but that has been repaired. Also tried an aftermarket coil, but spark seems the same with either coil. Is it possible to have a good spark, but the spark timing be off? How do you adjust the spark timing on this engine? I have seen several posts on how to verify spark timing, but none on how to adjust it. Could the problem be with the Stator or Pulse Generator? I still need to do a compression test and check valve gap. But a hand over the intake, a finger over the spark plug hole, and a hand over the exhaust tell me that the valves and piston are doing their job reasonably. Oil consumption has been very little, but it was low when the problems started.

I have a 2002 TRX 250EX which has been running well for the year I have had it. My son said it was running hot and then it died. Will not start now. Cranks over well, and seems to have a strong spark. Carburetor checks out OK, actually cleaner than I expected. Plug wire was pulled out of boot, but that has been repaired. Also tried an aftermarket coil, but spark seems the same with either coil. Is it possible to have a good spark, but the spark timing be off? How do you adjust the spark timing on this engine? I have seen several posts on how to verify spark timing, but none on how to adjust it. Could the problem be with the Stator or Pulse Generator? I still need to do a compression test and check valve gap. But a hand over the intake, a finger over the spark plug hole, and a hand over the exhaust tell me that the valves and piston are doing their job reasonably. Oil consumption has been very little, but it was low when the problems started.