Crankcase Vent

I recently purchased an '03 XR650R with about 400 miles on it, "uncorked" and with a Baja Designs kit installed. Yesterday I was in the process of removing the rear subframe and shock and noticed that the crankcase vent hose is routed on top of the airbox and ziptied to the subframe with nothing attached to the end. Is this OK or should a vent be attached to the end? Also is anyone running the crankcase vent down by the rear shock? Thanks

The vent hose should be attached to a nipple on top of the airbox itself. :naughty:

Venting to the atmosphere opens the possibility of water and dust entering the crankcase..... and thats not good.

The vent hose should be attached to a nipple on top of the airbox itself. :naughty:

Venting to the atmosphere opens the possibility of water and dust entering the crankcase..... and thats not good.

Exactly, You need to fix it before you ride it........... :naughty:

I installed the BAJA Design block off kit for removing the smog pump. They provided a cap for the airbox and a valve or breather for the hose and then you are to cable tie it to the frame.

I don't know about 650R's, but for quite a few years the 49 state 600 & 400Rs came stock with a crankcase vent that connected to a T, with one line venting to the atmosphere, the other line dropped down behind the crankcase to drain, with a slit cap on it. The post 97 California models have the separator unit with a drain, and another hose vented to the airbox or rubber airbox bellows (my 2003 XR4 came set up like this).

I must assume that the 49 state vent system did not allow dirt, etc into the gearbox or Honda would have eliminated it long ago for all XRs. While a single cylinder crankcase breathes in and out somewhat, blow-by gasses would cause the net flow to be outward. I think I'll keep the separator on my XR4, though; I doubt it slows me down much!

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