2014 Yz450 Crank Breather Mod

I checked my valves and noticed dirt getting into the valve cover through the breather tube so I'm definitely going to do this mod and thought I would share these photos of what I found. I'm wondering if anyone has put foam into the breather cavity in the head to catch this dirt as a alternative to re routing the breather tube?would that be a no no? Just an idea. Re routing the breather tube will be next on my list..

1418402044546.jpg

1418402067767.jpg

1418402086640.jpg

1418402114134.jpg

Stuffing the tube with foam would probably restrict the crankcase ventilation excessively, and you would be liable to blow the "half moons" out at the cam cover.  You can, however, find crankcase breather filters at auto parts stores in with the "self-help" odds and ends.  Most of them will work, but be sure the inlet barb for the hose is a half inch (12mm), and remember to keep it cleaned.

That's a good Idea too I don't really want to cut into the air boot

One of the reasons I haven't done this myself, besides the fact that I don't have a problem with dirt intrusion, is the lack of a way to route the rear-running hose from the engine compartment, past the shock hanger (or over it) and into the air box.   If I were more inspired, I would work on it. 

I drop coin for the thumper breather valve

It works!

and makes a farting noise when you shut down;)

One of the reasons I haven't done this myself, besides the fact that I don't have a problem with dirt intrusion, is the lack of a way to route the rear-running hose from the engine compartment, past the shock hanger (or over it) and into the air box.   If I were more inspired, I would work on it. 

Something like this? ....

 

                 https://www.youtube.com/watch?v=EaHnq0_0KJY&index=12&list=FLL4iETP1sQsW2vb4i7cuAnw

Not exactly.  The airbox end needs a filter because the hose run back to the engine from there is short, and the '06-'09 air box is an unusually dusty place.  

So I checked my valve cover again and there is still debris getting in through the breather tube..sand and even some grass or something so I re routed the tube and added a breather at the end. I didn't realize how large the filter I ordered was. But it works . I did my best to not kink or restrict the tube and found the only place I could mount the filter. Whatcha think?

1426530657158.jpg

1426530669666.jpg

1426530681321.jpg

1426530701584.jpg

1426530717190.jpg

1426530731568.jpg

1426530749906.jpg

So I checked my valve cover again and there is still debris getting in through the breather tube..sand and even some grass or something so I re routed the tube and added a breather at the end. I didn't realize how large the filter I ordered was. But it works . I did my best to not kink or restrict the tube and found the only place I could mount the filter. Whatcha think?

 

If you had to re-order a breather what size would you get?

If you had to re-order a breather what size would you get?

1.5 " or smaller...mine is 2" I beleve which is large to fit it places. The breather doesn't need a large filter

The breather is an avenue for up to 450cc of air plus combustion gasses either coming or going with each half turn of the crankshaft.  Restrict it with too small a filter, and you'll start pushing you cam box gaskets out.

The breather is an avenue for up to 450cc of air plus combustion gasses either coming or going with each half turn of the crankshaft. Restrict it with too small a filter, and you'll start pushing you cam box gaskets out.

that is true! I just think the 2" breather is a little overkill :D

I learned the hard way this weekend, sunk my bike in a very soft sandy creek crossing and it suck it into engine.

My oil filter is completely picked with sand. I don't even think I am going to bother taking it apart.

What is the best option to put a filter on the end or to reroute it to the airbox?

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now