i just finished the rebuilding the top end of our trx250x. it started on the second kick. started a few more times on the first kick. then the starter got stiff ........... seemed like the decompressor quit working. adusted that and it restarted but it did not want to rev and it stalled again. i have spark and every now and then the kickstart get stiff when i try to kick. any ideas?
dan

 

well i know why it started and stopped. i noticed the new header pipe turning cherry red. i pulled the plug and found white deposit on tip. it is overheating and within 2 minutes of starting the engine. i put a 12:1 piston in it along with a fmf pipe and exhaust. what the next step changing the plug range and jetting? i know this carb has a needle valve to adjust but do you change jets to adjust for richness like a 2 stroke?

 

Yes, you will definitely need to re-jet. In addition to rejetting, you want to be conscious of fuel type with the 12:1 compression ratio. If you're not already using race gas, you might want to think about it. Start with at least a 93 or 94 octane pump gas and pay attention to the motor. If you notice any pre-ignition or detonation then your octane level is too low. Try a 50/50 blend and see how that works.

 

thanks. i just picked up a couple of mains and 1 pilot and a can of race gas. never new an engine could heat up so fast. when i brought my cylinder for the boring i asked about a 12:1 piston and fmf exhaust. they said premium gas would be required and jetting would probably be ok. now his boss saying no way ......... race fuel and jetting required. anyway thanks for your help!

 

by the way i just noticed you ride a speed. i got a cannibal this february (never have to jet it!) i love it. how do you like your ride?

 

I love my Cannondale!! It's a very different quad and it takes some getting used to (I got mine in December and I'm still adjusting). Different riding style required, different ergonomics, different power delivery, different maintenance, etc. I'll always have a place in my heart for my old 250R, though.