weird stupid plug thingy

I have a 04 WR450F. On the front of the motor there is a weird rubberized plug that plugs a hole in the motor. anyway the plug falls out and hot oil drips all over my right leg. ive had to buy 3 plugs already. if anybody knows what im talking about and how to fix this little prob. please let me know. Thanks. Jake :D

I think that is the decomp plug you are talking about. TT store sells them with the ability to lock them with the existing side bolt. :D

I think that is the decomp plug you are talking about. TT store sells them with the ability to lock them with the existing side bolt. :D
Buy one of These , then check your breather to make sure it isn't pinched off or blocked.

The TT decomp plug mentioned by Greyracer will solve your problem, just don't over tighten the retention screw. It only gets tightened to 5 ft/lbs and a drop of red loctite on the threads won't hurt either.

What I can't figure is out it why the 03 and up still have a plug in that location. With auto decompress it's no longer used. Did Yamaha have a bunch of 426 heads they wanted to use up

For the 03's and newer Yamaha still lists the manual decomp parts kit as an option. Some guys like both for clearing their engine after submerging it. I don't think Yamaha sold many of the kits, especially after everyone who converted their 00-02 bikes over they were giving the manual decomps away on TT.

For the 03's and newer Yamaha still lists the manual decomp parts kit as an option. Some guys like both for clearing their engine after submerging it. I don't think Yamaha sold many of the kits, especially after everyone who converted their 00-02 bikes over they were giving the manual decomps away on TT.

Cool..... I learn something new every day :D

For the 03's and newer Yamaha still lists the manual decomp parts kit as an option. Some guys like both for clearing their engine after submerging it. I don't think Yamaha sold many of the kits, especially after everyone who converted their 00-02 bikes over they were giving the manual decomps away on TT.

I think they were just too cheap to re-tool. Lame because they could have eliminated the plug and bolt, along with the labor to install the parts :D

Retooling expense isn't the answer. The 450 head is already a totally different part. They provided the option deliberately. As old school as I am, I originally intended to buy the kit after I got the 450, but after owning the thing for a while, I just don't see a reason.

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