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Motorcycle Repair/pw50 spitting oil through exhaust...


Hello. Have recently bought my son pw50 wen first starting its kicking out white smoke had a look for oil leaks ect. Have found shes spitting oil through exhaust when revving her up is this just due to high oil to fuel mix or something lyk a perishd seal or are am i going to have to replace pistons. Thanks rossco.

Hello Rossco,

What's important for me to know, in order to troubleshoot accurately, is if you bought it new
or used.
If it's used, first thing is, if it holds idle. If it does, it's most unlikely to have seal or
piston/rings problem. If it doesn't, first check transmission oil for gasoline odor. If it smells gasoline, there is probably a crankshaft seal problem.
Next check starter (choke) cable. It may stick and hold choke open.
Then check the part of throttle cable that goes to the oil pump. Same here, it may stick.
Open the cover, actuate throttle and check oil pump for smooth operation.

Check all of the above and get back to me if nothing works. We'll figure it out...

Best Regards to you and your son!

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Lazaros Ampatzidis


I can help you on EVERY issue involving POST-1980 Japanese Motorcycles plus KTM and Husaberg. My field of expertise includes Engine, Transmission, Fuel system (carburation & EFI),Electrics and Electronics. Maintenance, repair and tuning. Road and off-road suspension tuning. Please don't ask me about non-Japanese Motorcycle, especially American built on which I have low to zero experience.


I'm a rider and hobbyist since childhood. 25 years motorcycle workshop mechanic.15 years motorcycle racing mechanic. In order of experience high to low:Kawasaki,Suzuki,Honda,Yamaha,KTM,Husaberg.

Hellenic (Greek) Technical School.Internal Combustion Engines Engineer. Automotive Electronics.

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