decomp plug leak

4 replies to this topic
  • rush66

Posted April 03, 2005 - 04:15 PM


I just got my bike back together a couple of days ago and got the chance to go for a ride and everything worked great except I noticed a very small leak from the decompression lever hole where I just put a tt plug.

I've had the 450 cam in my bike for awhile but just left the lever and spring there I put in the tt plug while I had everything apart. When I put the retention screw in I geuss I cross threaded the bolt and managed to strip the threads in the hole so I had to pry the plug out so I could tap the stripped hole. Upon doing so I think I might have torn the stock seal. I was looking at the seal and it's in there pretty good, can they come out ? I know they sell the replacement lip seals but if I can't get the stock seal out could I try some sort of other sealant?

thanks for the help

  • 02YZ426

Posted April 03, 2005 - 04:23 PM


Did you put the new seal in when you installed the TT plug? You should be able to carefully pry the old seal out with a flathead screwdriver. I just put the TT plug in my bike and the seal came out with no trouble at all. Just make sure you dont mark up the sealing surface in the case when taking the old seal out. :naughty:

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

Posted April 03, 2005 - 07:07 PM


If it's one of the older type seals with the steel exposed, it can be pretty tough, but if you're careful, you can get it out with a screwdriver as described.

Install the new seal by sliding it onto the plug, and then letting the plug push it in. You can use a large pair of "channel-lock" pliers to push the plug and seal into place by grabbing the plug with one jaw and the head behind the lock bolt boss with the other.

Don't strip it again. The mistake that is usually made is that the retention groove in the plug is not lined up with the lock bolt, and there are not very many threads engaged when the bolt gets tightened. The head of the bolt should bottom with very little resistance if everything's in the right place.

  • cowboyona426

Posted April 03, 2005 - 08:52 PM


I found it easier to remove the seal with the rad removed. With the rad in there it's hard to pop that bugger out.

  • Vibeguy

Posted April 03, 2005 - 10:49 PM



I manufacture the decomp plugs for TT, PM me with your mailing address and I'll get a new seal out to you asap tomorrow N/C.


Related Content


Snake pit oct 30th by The Anvil

Dirt Bike   Dirt Bike Regional Discussion   California
  • Hot  293 replies


Dirt Bike   Make / Model Specific   Yamaha   YZ 400/426/450
  • Hot  30 replies

Should I buy this bike? help....... by Numsa Hul

Dirt Bike   General Dirt Bike Forums   What bike should I buy?
  • * * * * *
  • 10 replies

Is it worth it? (Cam and High compression piston) by macgi77

Dirt Bike   Make / Model Specific   Honda   CRF 150/230 F/L
  • Hot  36 replies

Megabomb Fitment by 288yz450

Dirt Bike   Make / Model Specific   Yamaha   YZ 400/426/450
  • 1 reply

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.