If you haven't figured anything out this may help. I don't have a honda but my 350warrior was doing the samething it wouldn't start. I ran it out of gas one day and filled up but still wouldn't start, the only way it would start and idle is if the choke was all the way out. So i took the carb. apart and checked the main jet and there was the tiniest piece of dirt caught in there so i blew it out with a compressor. After that it was already to go and had no problems starting.

 

Mine did the same,even after the W.B.rev mod and fmf power core 4 pipe,I ended up with using a #160 main jet and 8-1 inch holes /w filters in the air box lid and all is okay now,it is cold blooded still,but once warmed up,the plug reading is perfect.And leave your W.B.rev box on ,it gives you appox.1200 more rpm through out the power range,NOT just top end.
Change your plug and buy the hotter one #(9)on the pluginstead of #(8)and only start it when you want to ride it,the choke is only on for appox. 5 seconds,and no more problems....

2-2000 trx400ex's
1-1998 trx300ex
1-1997 cr80

 

<< And leave your W.B.rev box on ,it gives you appox.1200 more rpm through out the power range,NOT just top end >>


I don't get what your saying. I know it advances the timing slightly, but how can you gain 1200rpm's at all times? I say take it off, sell it on ebay, and have you stock CDI modified if you need the higher rev limit. Go to this site (click here) to see a dyno run on just how much more power a rev box makes.