Hello to all here. This is my first post. I have done alot of searching here and read the carb sticky and I just can't seem to find the answer to my question. First off I have an '01 xr50 with the only mod being the opened air box. My problem started yesterday with the idle. It will idle ok for a while then it will cut off. Also when you rev the bike the idle takes a long time to return back to the idle speed. I am sure that someone out there knows how to fix this. Thanks in advance for the help.

 

try lubing the cable and the throttle assembly

 

I have tried that. Thanks for the response. I have been browsing through a lot of threads and I see that you have some good answers. I also noticed that it will rev up a little just out of the blue. I thought maybe I had an air leak but I can't imagine where. I have checked the intake and the throttle boot?

 

let it sit there and idle while moving your bars around side to side. if the idle goes up as u move the bars, u will need to loosen the throttle cable adjustment just a tad. if thats not the solution, it could quite possibly be a vacuum leak.

 

spray starting fluid or carb cleaner around the intake,carb etc while its running, if theres a leak, when you spray it youll know

 

That's a great idea!
I should try that on my ct70, cus sometimes it runs like crap and I know the intake or carb. is at fault.

 

now that you have opened the airbox up your gonna need to tinker with the fuel screw .this dictates what your air fuel mixture is at idle

 

I have checked for leaks using carb cleaner and there is no change in idle. I rode for quite a while today and when I would stop it would idle for about 5 seconds and then die. I have been adjusting the air fuel screw to no avail. The bike runs great but just doesn't seem to want to idle.

 

just turn your idle up some, when mine was stock it would do that, only idle about 30 seconds and die

 

im gonna agre with hurricane on this
turn your idle up 1/4 turn and then reset your mixture screw
gonna take some tinkering be patient

 

don't forget to do a plug check after all the "tinkering"