head gasket


4 replies to this topic
  • chopp123

Posted February 13, 2011 - 12:20 PM

#1

anybody think its possible to suck the crank case pressure into the cyl throught the head gasket. no matter what i do my bike is poping and backfiring. changed electrical, carb, cant figure it out. has new piston and crank. noticed that some smoke was coming out the vent. wondereing if its sucking and then blowing the crank case pressure out. my head isnt warped eathier. timing is right, im completely lost

  • lumpy790

Posted February 13, 2011 - 12:39 PM

#2

I have herd of a slight exhaust leak at the header/muffler joint causing a back fire popping on decel.

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • chopp123

Posted February 13, 2011 - 01:45 PM

#3

its not that. im pretty sure im sucking antifreeze and air in that head gasket.must be a shit one. its at any point when i hit the throttle. and its violent. pipe is trying to break apart at the coupling.

  • lumpy790

Posted February 13, 2011 - 03:38 PM

#4

Typically a blown head gasket will push compressed air into the cooling system. An automotive CO2 sniffer will tell you if there is CO2 in the coolant. A coolant pressure test would push coolant into the cylinder.

  • chopp123

Posted February 14, 2011 - 04:16 PM

#5

the dam carb i bought on ebay had the slide upsidedown i dont know how my other motor ran for 2 years with it but that was the whole problem.





Related Content

Forums
Photo

BIGBORE FOR YZ450F 2006? by Taattie94


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

YZ450FX OR YZ450F by MESSMAKER


Dirt Bike   Make / Model Specific   Yamaha   YZ 400/426/450
  • Hot  30 replies
Wiki
WR Camshaft Swap Info - last post by jamesm113

WR Camshaft Swap Info


Articles
  • 0 replies
Forums
Photo

James Stewart back on a YZ450F by YamaLink


Dirt Bike   Special Interest Forums   Pro Racing
  • Hot  47 replies
Forums
Photo

05 yz450f not fast enough by RedeyeYZ


Dirt Bike   Make / Model Specific   Yamaha   YZ 400/426/450
  • Hot  38 replies
 
x

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.