stock jetting and rich? (93 xr250l)

So far I have found most everything I have needed with the good old search button (thanks everyone). But I'm a little puzzeled rite now.

When I got the bike it was a bitch to start. Did a valve adjustment and cleaned the carb and re-adjusted the air screw. But I had to close it to .5 turns from close. So I thought maybe the pilot jet was messed up.

I ordered a 40 pilot (stock 38) and installed it tonight. I got it to idle and reset the air screw (1.5 out) but now it bogs if i go past 1/8 throttle. I also put in a 9 plug to replace the 8. i don't know if this could cause it to bog.

Tomorrow i will try the 38 pilot again but is there a reason its running rich? I live a mile away from the ocean so I'm basically at sea level and the muffler baffle is out. I took the snorkel out also and the filter clean...

You sure you put the throttle valve in the right way? Put it in backwards and it will bog when you twist the throttle at all.

just curious, how loud is your bike without the baffle? and will removing the baffle make my bike run leaner? the baffle was taken out by the previous owner and i don't want to be running the bike to lean.

the throttle valve is in rite. it was running fine before i put the jet and plug in. i just cant figure out why i would be running rich with stock jetting. everything i have read says it come lean from the factory. and i have the muffler uncorked and the snorkel out. it also had been rebuilt before i bought it. he said he put in a .040 over weisco piston in it.

stan, it is loud with the baffel out. but not crazy. it really dosent bother me.i have a "L" and you have a "R" so i dont know if yours would be louder or not.

hmmm, i thought the bikes were saposed to be rich from the factory.

the truth is running rich can't really harm your engine, it causes some carbon build up and it may waste a little gas but running lean can cause way more serious problems to your engine.

how do you know its running rich? what are the simptoms?

Okay i think I got it now. i thought turning the air screw tighter made it run more lean but i makes it more rich. I got it to idle and start great now.

The other problem was the air box snorkle. It was fine untill I cleaned the air filter. I guess it was dirtier than it looked. I cleaned it at the same time I put the jet in so I thought the new jet was the problem. I put the snorkle back in and it runs better now.

I'm gonna put a 128 main in tonight and take the snorkle back out. Hope it works. Thanks

just so you know, the screw that adjusts the idle speed does not affect the mixture at all, if thats what you meant by air screw.

i know... im talking about the flat head screw on the bottom of the carb.

does a main jet from a xr250r fit in a xr250l... the jet i have is from a r (i think, maybe they sent me the wrong one) and it is hex shaped. the one i pulled out was a round flat jet. when i put it it seemed like it was hitting the bottom of the float bowl. maybe because of the pumper on the l carb? im ordering round main jets rite now in any case.

ya the carbs are different between the R and the L vertions so i wouldn't be surprised if the jets were diferent.....

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