I went for a ride and got home and i always check oil before and after a ride. This time the oil had a strong scent of gas! I recently rejetted with a 48 pilot jet which HMF recommends for the slip on and have a 172 main. What is causing this to smell this way!

 

ttt

 

Be sure to turn off your fuel petcock after your done riding, it can overflow from the carb bowl and run into your engine while setting.

 

could it be jetted to rich? I always shut the fuel off and let it run until it starves itself so i know that is not it, any other guesses please!

 

anyone please?!?!?

 

one last time please!

 

I donno exactly but i might be able to help. Think of all the ways gas could get into oil in a 4 stroker.
Piston seal? Sounds unlikely considering you starve it, but the rejetting coincidence is interesting...

Weird Valve problem? Any weird noises or inconsistent performance....?

Oil level. If it isn't higher than before you rode, one of two things happened- You burned exactly the same amount of lube as gas that got into the oil. Seems unlikely. OR There isn't too terribly much gas in there, or the gas smell is coming from somewhere else. Take a paper towel (CLEAN) and dip the tip into the oil hole. Step away from the gleaming yfz450 and take a whiff. Still have gas problems? I'm over and out.

 

A couple of times i thought that my oil smelled like gas, but i think that certain brands of oil can get a gassy smell when it's hot. If it was running smoothly and wasn't smoking then i doubt that the problem could have anything to do with your jetting. I would change the oil and see what happens next time you ride it.

 

I just recently had that same problem and it turned out that my piston was cracked.

 

Alright guys, yfz has the same symptoms. We switched to the ESR Airbox Eliminator without rejetting. Of course the bike sits there and gets hot while idling...too lean. Kill the bike after 5 mins of idling and check the oil and have gas in the oil...what in the world could be causing this? Put the stock air filter back on and change oil problem solved...somebody help a brother out. Thanks