Need advice. Bike will not run after rebuilt motor. Electrical?

Hey guys,

I rebuilt the motor on my 2005 CRF250R. Changed both the cylinder and piston. Rejetted the carburetor. Put a brand new spark plug in.

It was difficult to start, but I figured that it was due to my lack of knowledge about accelerator pump carbs. Once it did start it would run perfect and was super easy to start. I rode it around the parking lot at work for at least 20 minutes a few times.

Took it up to Tahoe last week. Left it parked in the garage where it was 15 degrees all week. Tried to start it after a week and impossible to get it to fire (boith when kicking and push starting). It will compression fire after trying long enough. But it doesn't start, idle or run.

Brought it back to the Bay Area, it's a lot warmer here and had the same issue. Could not get it to fire. It definitely compression fires when trying to push start.

I smell fuel after enough kicks and it compression fires so that pretty much leaves electrical issues as it seems to not be making a spark.

I disconnected the kill switch and that made no difference.

Any advice?

I will try to see if the plug is sparking ASAP.

Have you checked the valve clearances? This sounds like they tightened up and the 04 and 05 were notorious for having bad valves

Yes, I checked the valves. They were perfectly in spec.

When I pull the gas tank to check the plug, I will triple check the valves, but I've already checked them twice.

So... I was right, it was an electrical problem...

The spark plug wasn't torqued down tight enough :banghead:

I'm an idiot

Runs awesome now and figured out the proper starting procedure.

OK, there was a little more too it. The coil is burned out and I ordered a new one>

It starts perfect when I wiggle the old one. 3 kicks when cold tops :D

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