White smoke but smells oily.....

1 reply to this topic
  • mutiny5050

Posted September 08, 2015 - 10:13 AM


Well on the last round of the NHHA in Panaca I had a ton of Silt get through the filter and reek havoc on my plug, piston and carb. I tore the whole thing down and cleaned the piston, carb and replaced the plug. I put her together with no issues and she fired right up.  Took it for a test run and everything was good. 


The next day we went for a little put . I passed my buddy and he thought he was riding behind a 2 stroke. He said there was white smoke galore. When i was idling i reved it up and during the high rpm there was white smoke coming out. It smelt oily but the bike also smelt hot. The radiator fluid lowered so I think it is just a head gasket. 


My question is.... should I just replace the head gasket or get a new top end or rings just in case? Any other things you guys can think of to replace or look at?

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • grayracer513

Posted September 08, 2015 - 10:41 AM


First, understand that most people can't tell the difference between "white smoke" and the so-called "blue" smoke produced by oil burning.  To almost everyone, oil smoke looks much more white than blue. 


Supposedly, "blue" smoke is oil, and white "smoke" is coolant, but the fact is that coolant doesn't produce smoke at all; it produces steam, which can be easily distinguished from smoke by the fact that steam will vanish into the air as it cools, whereas oil smoke will only thin out and drift away.  Oil smoke and steam containing coolants also have distinctly different smells.


Even that doesn't entirely clear up the question (any puns are accidental).  The problem is that either or both of oil and coolant can enter the engine via a faulty head gasket.  If you just want to be sure, plan on replacing the rings and valve seals along with the gasket.  Evaluate the cylinder condition when you open it up, and decide whether either needs replacement or other work besides deglazing the bore. 

Related Content


yz400f throttle bog by yz400fmaniac

Dirt Bike   Make / Model Specific   Yamaha   YZ 400/426/450
  • * * * * *
  • Hot  28 replies

First Hare scramble tips by dhend8

Dirt Bike   General Dirt Bike Forums   General Dirt Bike Discussion
  • Hot  33 replies

Snake pit oct 30th by The Anvil

Dirt Bike   Dirt Bike Regional Discussion   California
  • Hot  35 replies

YZ450F 03 Sparks driving me crazy by SirAttard

Dirt Bike   Make / Model Specific   Yamaha   YZ 400/426/450
  • 5 replies

2016 YZ450 by CaptainKnobby

Dirt Bike   Dirt Bike Technical Forums   Suspension
  • Hot  59 replies

Join Our Community!

Even if you don't want to post, registered members get access to tools that make finding & following the good stuff easier.

If you enjoyed reading about "" here in the ThumperTalk archive, you'll LOVE our community. Come join ThumperTalk today!

The views and opinions expressed on this page are strictly those of the author, and have not been reviewed or approved by ThumperTalk.