97' XR 650L carb problems

Hello to all! I have ran into a problem trying to open up my 97' 650L. I decided to remove the smog crap and perform Dave's mods to my carb at the same time. My bike ran perfect before the modding began, but now not so much. I removed the snorkle, replaced the air filter with a UNI, jetted the carb with 58 pilot, 158 main, drilled the slide to 5/32 and shimmed the needle with a .025 shim. I think my bike is a California model, because it has the evap canister, charcoal canister and the other vacuum thing along with the air pump. I bought an IMS removal kit and removed everything but the charcoal canister. I basically did everything in accordance to this http://www.4strokes.com/forums/topic.asp?TOPIC_ID=16361

So I put everything back together and now the bike bairly runs. It is running so rich that it wont idle. I checked the float and it seems to be ok ie not overflowing. I checked the choke and it too seems ok. However, when i turn the gas off while its running, it smothes out nicely right before it runs out of fuel. It seems to run like the choke is all the way on without it being on if that makes sense. Anybody have any ideas on what the problem could be. I did find a small brass peice that looks like it presses in the front of the carb body next to the float bowl mount bolt but I am not sure. I replaced the 58 pilot with the stock 52 and it ran the same. Please help!!


I have a 97 XR600, and just rejetted my carb. While my bike didnt have any smog to begin with, I wound up using #68 slow jet (pilot) and #155 Main. Fuel mix screw @ 2.5 turns out. Not sure if there is much diff between 97 600R/650L, but my bike really 'woke-up' with those changes. I am also using UNI filter. Good Luck!!

youre jetting is right on. couple things could have happened.

enrichener needle stuck open in its bore.

float needle stuck open, or float out of adjustment.

poss(not likely) the needle got caught on the main jet holder and is hanging open.

you followed those instructions to a T? recheck vacuum routing.

If took apart the the decel-enrichment thingie (diaphragm on right side of carb that vacuum line goes to) you may want to check that its back together properly. My bike exhibited the same symptoms until I took it apart at reassembled it.

Thanks for the replys, i found the problem. The little brass piece that fell out was the needle guide that is held in place by the main jet assembly. I installed that and the bike runs like a champ. For the newbs out there, make sure that you can see the brass tube sticking through the bottom of the carb bore.


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