650r carb adjustments

Need help. Lately, my xr650r is stalling. When I come to a stop it may idle fine, but usually just burps and dies. It then takes atleast a few kicks to start back up. Also, if I let it idle for a few seconds then quickly blip the throttle it will burp and die. I suspect it is too rich or too lean, I just don't know which. The mods to this bike are 16211-mbn-640=opened carb intake, #170 main jet, and #68 jet, and uncorked muffler. The bike has just developed this problem and have not had any issues before. I live in Dallas and temps have been over 100 degrees. I have raised the idle to keep it from stalling at lights while I find the real problem. Also, when running about 80+ sometimes it will "pop". What do I adjust and what direction. Thanks for you help. I searched for a helpful link but couldn't find one.

Man, I had the exact same problems that you do with my Pig, tried every combination of jetting in the world and the performance was still unsatisfactory.

I finally broke down and bought a Edelbrock Quicksilver carb.

All problems solved, great carb.

It sounds like the float went out of adjustment. Its on the verge of flooding all the time. Readjust the float level to shut off the fuel 2mm sooner than the stock setting. Does this happen most often just after climbing hills (they don't have to be steep hills)?

Some desert racers only like to set the floats 1/2 to 1mm sooner shut off than stock float level. If your not racing and riding slower mountainous single track 2mm works better in my opinion. Just play with the float setting till you find the one that works best for your riding.

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