gas in oil

8 replies to this topic
  • ncmountainman

Posted April 20, 2004 - 12:04 PM


my new wr450 has about 300mi on it after all the standard mods with the stock jetting(air fuel 2 turns out) after the scond oil change i noticed the smell of gas in the oil. ok i thought maybe it was because i dumped that day(if you aint wreckin you aint ridin)so changed it again went ridin didnt wreck and the same thing! it runs fine no stutters nothin it was rnnin a little hot but not over heating i ride between 2000-5000ft anyone have any input thanx

  • Hamish

Posted April 21, 2004 - 12:21 AM


I can only talk from expereince. If I leave the fuel tap turned on on my 2 smoke, fuel somehow trickles down the inlet track and fills the crankcase (probably due to the high float level), and finially the expansion chamber. The fuel then evaporates and leaves the crankcase full of oil. When I finally got it started it spraypainted the side of my mums house with black oil. :)

In your case, any fuel that trickled out of the carb would get to the sump via the ring gap. I'd check the float level, and remember to turn off the fuel tap when in transit. If the engine is in good condition, it would be virtually impossible for fuel to get in the oil when the bike was running. The only engines that normally suffer fuel in oil syndrome are fuel injected methanolengines.
my 2 cents,

  • The_Missile

Posted April 21, 2004 - 12:52 AM


On my WR the carb reservoir is at the base of the carb and fuel gets into the engine either via the squirt or through the 'emulsion tube'? If the bike is sitting I dont see physically how gasoline would end up trickling from the carb and into the cylinder? It also has to get past the valves unless not at tdc. Am I missing something ?

  • Hamish

Posted April 21, 2004 - 01:25 AM


beats me how it happens..but it happened to me. maybe splash effect whilst in transit


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

Posted April 21, 2004 - 01:45 AM


Ok I see that, I have experienced myself trailering with the fuel petcock on and having a flooded cylinder. Always trailer with the petcock closed from now on. No problems.

  • ncmountainman

Posted April 21, 2004 - 05:19 AM


i dont know either after the first time i even tried shutting the fuel off before i killed the engine and made sure it was off in transit ,sitting still ,everywhere! my next try will be to disable the ACV. will let you know. thanx

  • x2smoker

Posted April 21, 2004 - 07:10 AM


Me thinks that when you are not looking, the neihbor kids are sitting on it making "vroooom vroooom" sounds and twisting the throttle :D. The day I bought mine, they had gas running out the drain tubes before I even started it up :).


  • The_Missile

Posted April 22, 2004 - 01:15 AM


There was some sorry assed guy a long while back who had the devil of a time starting his bike for many weeks. Too rich. Couldnt understand....until that is his wife informed him that his kids would do the vroom vroom thing but it was ok cause she kept an eye on them or something like that!! LMAO.

I'm not sure he has kids anymore!! Was that you x2smoker!!!

  • ncmountainman

Posted April 22, 2004 - 05:59 AM


after deep consideration i think it may be carless loading and unloading on the trailer (we load four bikes onto a rather small trailer)that might be giving the vroom vroom effect :) :D seeing as the only kid i allow within 50ft of me or my bike is 13 and has his own vroom vroom! so before i try discombobulating the acv i'll try to make some sort of throttle lock. thanx for helping me figure it out. hopefully


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.