my friend and I cleaned the carbs, since then the sled has run poorly. We replaced the fuel pump and battery. It ran fine but seemed to backfire thru the exhaust on deceleration and on idle continued popping. We checked the reeds, they looked okay. The sled ran fine, strong and smooth then this. Any ideas before I give up and bring it to a dealer????
yamaholic22
Active member
Check the specs on the stator, primary coils and secondary coils, as well as the spark plug boots. May have an ignition misfire.
EDIT: I just noticed you said that it ran poorly only AFTER cleaning the carbs. So something went wrong or wasn't assembled right after cleaning the carbs. Did you pull the mains AND the pilots? Could you plainly see light through them all? Where are the fuel screws set? Verify float height and adjust if necessary, they are often out of spec if never adjusted before.
EDIT: I just noticed you said that it ran poorly only AFTER cleaning the carbs. So something went wrong or wasn't assembled right after cleaning the carbs. Did you pull the mains AND the pilots? Could you plainly see light through them all? Where are the fuel screws set? Verify float height and adjust if necessary, they are often out of spec if never adjusted before.
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daman
New member
Or is it poping under load also???
are you sure you cleand the carbs right??,blew evrything out with shop
air???? then checked/set to spec????
are you sure you cleand the carbs right??,blew evrything out with shop
air???? then checked/set to spec????
YAMAHIZAL700
New member
DId that year viper have the tors? If so, try bypassing by plugging the wires together.
Did a compression test on sled-1=90, 2=130, 3=95. I can't figure out why this happened.The sled ran great. The power valves were stuck, but that should not hurt compression. The rings must be cooked on 1&2 cyl's. I wonder if I should buy a complete Wiseco piston kit(sk#1325) or rings and a gasket set.Then trade it in on a new Apex GT.
I would pull off the topend first and see how bad it is, sounds like you either have stuck rings(closed) or smeared ringlands. if you have 90lbs of compression its not too bad, but it needs attention.
Had a mechanic take the top end apart. It seems when the carbs were cleaned and put back on, the oiler cable came out and got hung up. The oil went into carbs, motor, then heated up in the cylinders and stuck the rings closed causing the popping and lower compression. Hopefully that is the answer. I will let you know how it all turns out. Hey guys thanks for all your help. GREAT SITE!!!!!
daman
New member
Huh???
that makes no sense...
that makes no sense...