250-500cc WR 250/300 Case and Carb Breather Mod

Thanks to all those who posted suggestion on how to bomb proof my 2011 WR300.

I have attached some photos of how I tackled the relocation of the crankcase breather and the top carburetor breathers. I couldn't find any photos to help me do it, that's why I took these.

I decided to re-rout them into the air box at a cost of a about $25 for extra hose and fittings.



I used two of these and a t-fitting.


I thought the top left hand side of the air box was probably the preferred entry point for the breathers. I did mount them a little too close to the ring that seats the air filter.



I positioned the fittings upwards to stop water running straight into the crankcase (I don't plan on testing it out in a deep hole)

Both case and carb breathers fitted, I also used a little sikaflex around the thread and nuts.



Fittings from inside air box.


The tee fitting used to connect the two top carb breathers into a single fitting air box fitting.


Hope this helps others. Feel free to point out possible problems with this set up.

Cheers!

nice work...you make my job of routing up under tank and cable tying look bad lol

Thanks! I was going to just cable tie them under the seat. But the space is already taken up with a spare clutch and break lever tied to the frame.
Cheers

curious if any oil will get in your air box form the crank case breather? On my 06 I ran it up under the tank and back down and it still puked a bit of oil on hard MX tracks. Let me know how it works for you.

Yeah will do! Doing a few more mods before next ride so it will be a little while.

For the carb breathers i just used a pc vent kit. But id like to see more on how you guys vent the crankcase breather.

I ran mine up and over the rear shock looped the hose and then back down out the bottom to make the oil have a long path to travel before it can get out.

Its not really a problem oil coming out, more that water gets into the gearbox.

Oh well if too much oil comes out at least its going over my air cleaner!

Ive just invented an automatic filter oiling system!