Newbie question re: carbureator

Hello all.

I am new to this forum, but have been reading it for a few days now (as soon as I found it!) I did a lot of riding in my younger years, then took a few off to go to college, and start a family. I recently bought a 2000 XR650R on e-bay. It still had the tits on the tires, and is like brand new. It is the first thumper I've owned, and I love it! I did the power up kit after my first ride, and it made a huge difference. My question is regarding the carbureator. I have been into Mikunis (I know this one is not a Mikuni, but it seems pretty similar.) on several occasions before, so they don't scare me, but I have a small problem now that I'm not sure about. I was getting a lot of overflow gas out of the overflow vent when tipped on the kick stand, so I took the carb off, checked the needle and seat and they were both clean. The carb looked good too. (it had set for a couple of months without being started) I adjusted the float tab up, which took care of the overflow problem, but now it won't idle well. I didn't go radical with the float adjustment, but could that be the cause? If not, then I probably have some crap in the pilot. I'm running the 68s, that came with the jet kit. Mileage wise, I'm guessing that the bike has less than one hundred miles on it. I've only put about 50 miles on it since I've had it, and I've done more damage to the tires then they had on it when I got it. My tank vent is clear, and I'm realively certain that none of the other vent tubes are pinched. Any suggestions??



P.S. Stonewall, your posted picture is sweeeeeeet! I need to find a re-fueler like that!! :)

First of all congratulations on the new bike!! If the only thing you changed was the float level and imediately you got the bad idle then my guess would be it was changed just a bit to much. I had to adjust my level too to eliminate the overflow problem but I haven't had any run problems. All things being equal you may want to pull the carb and inspect just to make sure you don't have a plugged jet and perhaps tweek the float level if need be..

P.S. Stonewall, your posted picture is sweeeeeeet! I need to find a re-fueler like that!!

Thanks!! I like the fuel overflow problem. :) It just means she has to refuel me more often. :D :D

Hey Winkel.. Let me help you out here, I had the same exact problem with my 650R a few months after I bought it. It had also been sitting for about a year.

The problem is not the float level, but probably a white corrosive deposit on the float needle SEAT, which is the part the rubber needle seals to.

First, readjust the float back to specs. Then, use a Q-tip with b-12 on it, and clean off the needle seat completely, even if it doesn't look dirty, there is probably a small amount of white deposits on it which keeps the rubber needle from sealing. Problem should be solved.

Hope this works for ya. :)

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