Yamaha Forum

**JimR** · 11-06-2009, 11:17 AM

We all know older Yamaha 4 strokes can be a pain to sort out ... leave a comment here & I guess it will get fixed

78xt500 · 01-10-2010, 09:40 PM

Hi I have a 1978 Yamaha xt500 that seemed to run fine after I rebuilt the carb but now it has problems running right. I replaced all the gaskets and plungers and cleaned the carb a bit recently. The bike seemed to run fine but now it is starting to have problems. The first thing I noticed was fuel spewing out of the overflow on the carb. Not to long after that had happened, the bike started running funny, The bike wants to bog out when given throttle. It does seem to idle decent though. When I first start it I can give it throttle and it will rev up all right but after a few revs(like 2) it starts to bog out bad. Does anyone have any suggestions? Do you think the float stuck??

**JimR** · 01-11-2010, 09:28 AM

hmm I guess you have rebult the carb incorrectly
Take it off again and check the jet needle (you may know it as the valve seat assy) and the float for the correct height as it ran ok before I guess you have 'manufactured' a fault. Does the carb have an accelerator pump ? if so did you replace the diaphram there ?
Regards Jim

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01-10-2010, 09:40 PM	#2
78xt500 Join Date: Jan 2010 Posts: 1 Thanks: 0 Thanked 0 Times in 0 Posts	Hi I have a 1978 Yamaha xt500 that seemed to run fine after I rebuilt the carb but now it has problems running right. I replaced all the gaskets and plungers and cleaned the carb a bit recently. The bike seemed to run fine but now it is starting to have problems. The first thing I noticed was fuel spewing out of the overflow on the carb. Not to long after that had happened, the bike started running funny, The bike wants to bog out when given throttle. It does seem to idle decent though. When I first start it I can give it throttle and it will rev up all right but after a few revs(like 2) it starts to bog out bad. Does anyone have any suggestions? Do you think the float stuck??