91 Cr250 Fouling Plugs

[nosstang]

need help I'm at the end of my rope with this bike.I have replaced the crank seal,new air filter,rejetted the carb 182 on the main and 53 on the slow jet,check float level numerus times,compression is around 160,I did notice a red spark out of the plug when I was checking for ign fire,Could this be the cause of my problem????? I can put a new plug in the bike runs great for about a hour and then it will start fould one every 20 mins or so. Doesnt matter weather im riding the balls off the bike or or trail riding same problem.The plug will be soaking wet with gas. Please help thanks Robbie

 

[Var]

I'm running 175/50 jets on my 90 cr250 and it seems a little rich still on the pilot. I'm gonna try a 48 and this is at sea level. where'd u come up with those jet sizes?

 

[nosstang]

thats whats stamped on the jetts.I orderes the factory whic are bigger I havent put them in I figured it would make it worse since they are bigger????? but I bought the bike used so I dont know where they got those jetts

 

[Var]

the stock size for my 90 are 175/55, or at least that's what the dealer told me.

 

[N3WFI3]

ya i fouled a plug on my bike today and got a flat tire :(
gunna drop the main and pilot one size and test it with a new plug in
in a few weeks time

 

[KX250Dad]

The 160 seems a bit on the low side to me... 190-200++ In so far as fire, red? I figure a bright strong orange to a bluish white.... maybe a hotter plug.
Good Luck