Stripped Bolt on cylinder

While adjusting the valves and timing I stripped the bolt that holds on the decompression actuator on the right side of the cylinder. It's tapped right into the cylinder and starting to leak oil. The bolt is kind of a funky design too. I jb welded it a few weeks ago before an enduro to get by but now it's leaking again. Any suggestions?

Check to see if you can order it through Yamaha.

If it is a stud, I have removed mine buy cranking a vice-grip on it and spinning it out. This has worked beautifully on the aluminum studs I stripped out on my Honda's Showa fork legs. I replaced them w/ steel studs from the hardware store, and used lockwashers to prevent overtightening the nuts (I could watch the lockwasher compress).


99 WR, all YZ mods, de-octopused, OEM YZ tank and IMS seat, jetting by Clark, got forked by Pro Action.


For clarification: WE'LL be having a KICK ASS time in Moab!! Right Mitch?!!

The bolt seems to be tapped directly into the soft aluminum cylinder and it is the cylinder that is stripped not the bolt.

I will bet you can you drill it out use a heli coil insert kit and then seal the whole thing with a copper washer and some Gaskachinch?? You will have to pay particular attention to the depth of the heli-coil insert but it is repairable on the bike if you are careful and very clean on with your work habbits and gard against any chips getting into the engine during drilling, etc.

If you do not feel comfortable doing it yourself take the head off and take it or mail it to a reputable shop and they can professionally repair it. It is definatly fixible.


[This message has been edited by Clark Mason (edited 07-10-2000).]


I did the same thing the first time I changed to YZ timing and did my valves. It went back in but it never torqued down and I know I stripped it.

The next time I will have to change my exhaust valve shims, I just know it will stip out for good. It isn't leaking yet or coming out but I'm screwed the next time.

My only thought will be to get it re-tapped. I have stripped about 3 bolt holes so far on the aluminum parts of this bike. I am compensating with lock washers for the time being.


Dougie, '99 WR400

Mods: YZ timing, Race Tech Suspension, FMF PC IV, FMF Hi FLo Moto, YZ seat, IMS 3.3 tank, One Industries Graphics, Renthal bars, 14/52 gearing.

[This message has been edited by Dougie (edited 07-13-2000).]

As Clark mentioned, the helio-coil is the only way for a sure fix.

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