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2003 XR650L Carb woes part throttle bog

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I've been snooping around here for the past week and elsewhere on the web trying to research why the bike I just purchased last weekend bogs and chokes at part throttle. The snorkle has been removed, and has a clean uni filter in it. It also has a FMF exhaust that has a Q on the side (rather loud).

When I got it the guy had just cleaned out the carb and installed an FMF jet kit (165 main, stock pilot, different needle in 3rd clip, shorter spring). It would idle but part throttle it would surge and bog a little. I assumed it needed a larger pilot jet so I ordered some, (55 and 58 Keihin) Well the problem was worse with the 55 and 165. It would not idle and belched black smoke when given more throttle. The plug was very sooty as well. I'm in Texas at about 600' so I am shocked the larger pilot didn't work.

It also now has a drilled slide, with the stock spring back in. I have tried every combination I can think of and am now an expert at removing the carb on this bike. Basically with the 50s stock pilot, and 160 main with FMF needle, drilled slide and stock spring is the best I can get it to run / idle, but its still almost not rideable. It will idle better but there is no low speed cruising, its either idle or wide open. I have also checked the valves twice and they are spot on. I read elsewhere that the choke needs to be correctly adjusted, and plan to check that again this weekend. Also I read to check the needle seat if the pilot jet emulsifier tube has been removed, and will do that as well. Is there anything I'm missing here? I just want to ride my new toy!

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I just noticed that I do not have the slosh baffle either, how would this affect my carb?

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I've been snooping around here for the past week and elsewhere on the web trying to research why the bike I just purchased last weekend bogs and chokes at part throttle. The snorkle has been removed, and has a clean uni filter in it. It also has a FMF exhaust that has a Q on the side (rather loud).

When I got it the guy had just cleaned out the carb and installed an FMF jet kit (165 main, stock pilot, different needle in 3rd clip, shorter spring). It would idle but part throttle it would surge and bog a little. I assumed it needed a larger pilot jet so I ordered some, (55 and 58 Keihin) Well the problem was worse with the 55 and 165. It would not idle and belched black smoke when given more throttle. The plug was very sooty as well. I'm in Texas at about 600' so I am shocked the larger pilot didn't work.

It also now has a drilled slide, with the stock spring back in. I have tried every combination I can think of and am now an expert at removing the carb on this bike. Basically with the 50s stock pilot, and 160 main with FMF needle, drilled slide and stock spring is the best I can get it to run / idle, but its still almost not rideable. It will idle better but there is no low speed cruising, its either idle or wide open. I have also checked the valves twice and they are spot on. I read elsewhere that the choke needs to be correctly adjusted, and plan to check that again this weekend. Also I read to check the needle seat if the pilot jet emulsifier tube has been removed, and will do that as well. Is there anything I'm missing here? I just want to ride my new toy!

Try running it with the air cleaner side cover removed, better or worse? Check the plastic widget that holds in the needle, if not installed correctly they come loose and cause problems. Make sure you have the diaphragm on the throttle valve installed correctly and no holes. All the vacuum lines are correct? Good luck you'll get it.

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Got home and took the carb off again, and low and behold the slide needle seat is missing! I thought these things were pressed in, but apparently not. I e-mailed the guy I bought it from who dipped the carb and maybe he still has it. If not where can I order it from?

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Got home and took the carb off again, and low and behold the slide needle seat is missing! I thought these things were pressed in, but apparently not. I e-mailed the guy I bought it from who dipped the carb and maybe he still has it. If not where can I order it from?

Anyone who sells Honda/Keihin OEM parts. Dealers, TT, Chapparal,

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Part came in today~ she rips! Went with the 55 pilot and the 165 main with dynojet needle and 2 turns out on the mixture screw for now, seems to idle well and pulls strong through all throttle positions! thanks for all the info on the site!

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Got home and took the carb off again, and low and behold the slide needle seat is missing! I thought these things were pressed in, but apparently not. I e-mailed the guy I bought it from who dipped the carb and maybe he still has it. If not where can I order it from?

Just so we know, are you talking about the plastic retainer that goes under the spring and holds the needle in the throttle slide?

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negatory, it was the brass piece that fits under the main jet emulsifier tube. The slide needle goes through it from the carb throat.

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