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Jeremy R.
Jeremy R., Mechanic
Category: Motorcycle
Satisfied Customers: 9020
Experience:  15+ Yrs Factory certified technician and business owner.
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I have a 2004 yahama Bsw zuma 50 cc I just bought and am trying

Customer Question

I have a 2004 yahama Bsw zuma 50 cc I just bought and am trying to restore . It run but when I ride it it reves up but idles down about half way and after a couple of seconds it drops down to an idle. What could cause this
Ps I have tried 2 different carb with the same result
Submitted: 2 years ago.
Category: Motorcycle
Expert:  Jeremy R. replied 2 years ago.
Hi there,I'm not quite sure I understand what you're saying.If you're sitting still on the stand and you rev it up.It will come back down at an odd rate because the belt drive and momentum from the rear tire will be pushing the engine along.If that's what you're saying then it's normal.If you're riding it and let off and stop and when you come to a stop and it still takes the motor a couple seconds to idle down then the problem is the mixture isn't correct.It's too lean.You can adjust the carb to fix this by turning the mixutre screw out 1/4 turn at a time.