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Motorcycle Repair/79 yamaha yamahopper scooter


Dorn D. Taft VI wrote at 2008-07-25 04:26:08
Your fuel flow is not fast enough to keep up with your carb.  Take out the petcock, if it has one and check the filters, or filter.  Seal it off and put some CLR or other rust remover in the tank with nuts and bolts: "follow instructions on bottle", then rattle it around for awhile.  This will get rid of the rust and varnish.  You MUST follow up with a rinse of water, then twice with gas to eliminate residual chemicals.  Do not use this method when there are any rubber gaskets present

matt wrote at 2009-07-03 08:10:34
probably sticky breather bearing in your gas cap (common). ride a bit (carefully) with cap just open to see if its the problem

matts moped mania wrote at 2014-09-06 13:49:23
Your fuel is restricted. Whether in the tank, lines, filter or carb you have a fuel issue. The float bowl is not filling fast enough to keep up with engine. Check fuel lines and filter for cracks or debris. If nothing is wrong there take carb apart and clean with carb cleaner paying special attention to the float and needle. Be sure the needle is not sticking. It should come down as the float does.  

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Mark Shively


Friends, I will be ending my services with AllExperts effective the first week of June, 2007. It's been a pleasure the past few years corresponding with the many of you. Respectfully, Mark Shively (Dayton, Ohio) ""


Graduate of the American Motorcycle Institute (AMI class 172), multi-factory trained technician, 7 years experience dealership technician & service manager, professional roadracing team technician. Court certified expert in area of motorcycle technology. State certified crash investigator. State certified commercial vehicle crash investigator. State certified forensics/evidence technician. State certified instructor; community college instructor. Privately servicing street motorcycles & ATV's, accident reconstructionists, and dealership turn-aways. I am not available as an expert witness.

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