WR 426 / 450 Oil Breather Pipe?

Hi Guys, 


I'm new to the forum but have viewed many topics and threads on here so hello from 'me' as this is my first post.


I have a WR426 2002. 


This morning I noticed a pipe leaking.  The pipe starts from the top of the engine head (Next to the spark plug). The pipe is thick and then steps down in size as it passes the carb..


I think the other end should attach somewhere. 


Please can some one tel me if it is a breather/overflow pipe or return pipe which should be attached!??!!


Many thanks!


Looks like the breather, but it's not routed the same as mine.  Mine goes to the front of the motor and dumps on the skidplate.

Thanks for the reply.

Yes, that all makes sense!

Does anyone's oil breather pipe ever kick out white/brown sludge?

I changed the oil recently and possibly filled it up a little too much.

Go to bikebandit .com and look up your bike and it will show the routing at both ends.


As SERVICE MANUAL will also explain it, which Yamaha provides for free on their website

Yamaha provides no owner service manuals for free on the US website, so when you say that, you point people down a dead end street. 


The manuals are downloadable from either Yamaha/Europe or .../Australia:






The breather's original routing is forward from the head to the frame down tube, down along the frame and under the ignition cover, dumping just below the end of the shifter.

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