Vent hose to airbox or not?

[Kivi]

Hi,
when I bought the bike the engine crankcase vent hose was open to vent to the atmosphere, below the engine. On the airbox, at the bottom of the box, there is a hole, which can accept this hose - appropriate diameters....
I was wondering if this hose should be routed to the air filter box or left to vent to atmosphere? Any impact on engine life, operation, performance, consumption, or...?

[timcosby]

either to the airbox or put a pcv valve on it so it doesnt suck dirt into engine.

[pete]

run the pipe up high then back down &
put a filter on the end of it if yer wish..



..

[Megadan]

IMHO the best way would be to run a hose as Pete suggests with a small breather filter on the end. You could combine this with the PCV valve/one way check valve idea timcosby mentioned.

That said, the airbox combined with the PCV valve will also work fine.

There are other options as well. It really just depends on how ambitious you are feeling.

[Ariel Red Hunter]

Originally Posted by Kivi

Hi,
when I bought the bike the engine crankcase vent hose was open to vent to the atmosphere, below the engine. On the airbox, at the bottom of the box, there is a hole, which can accept this hose - appropriate diameters....
I was wondering if this hose should be routed to the air filter box or left to vent to atmosphere? Any impact on engine life, operation, performance, consumption, or...?

A Positive Crankcase Valve (PCV) is my preferance. What you do with the hose after the PCV valve is up to your preferance. You can let it run up to the air box, or let it dangle under the engine. The main advantage to the PCV valve is that it only lets air out of the crankcase, and does not allow the engine to suck air back in. Thus it prevents dust or sandy air back in the crankcase. The secondary benefits are that the crankcase runs in a partial vacuum, which reduces fluctuating pressure on the seals, and less fogged oil caused by crankcase "panting". Not to mention a slight power increase, due to less crankcase air pumping. On car engines, when PCV valves were mandated in the USA, an un-expected side benefit was less oil consumption, as compared to a the previous road draft tube. If you decide to install a PCV unit, make sure the side you can blow through is on the engine side, so it lets air out, but not in...ARH

[Sochin]

I ordered a Microgard PCV112 from O'Reillys (You probably don't have this autopart store in Serbia?) and routed it to up and behing the airbox over the chain