Oil breathers

[Phill106]

Crank case breathers, are they worth the extra effort? Iv seen a couple welded into the gsxr11 clutch housing. Just wonder if they are actually beneficial? 

Edited November 29, 2015 by Phill106

[Oilyspanner]

I think it depends how much you've tuned your engine really. Bigger pistons will move more air around beneath the pistons for example , or on a tuned engine that revs harder- on a big block I think it's near a must, but for a  standard (ish) engine there's little need for extra venting. Most OC bikes have the vent on the cam cover.

[Captain Chaos]

They are never a bad thing. And as Spanner said, on tuned engines they are a must.

[Tony Nitrous]

If your going to do it do it right.

The one that thread into the filler hole are pretty poor, much too small an internal diameter.

Been there, done that, next one will be a weld in, big bore vent. 

 

Edited November 29, 2015 by Tony Nitrous

[Gixer1460]

Big bores and forced induction motors will all suffer ring blow by and crankcase compression - fact. Without increased breathing, you'll end up with blown seals and leaky gaskets - fact. Any added is a good option - my 1186 turbo had oil filler vent in dash 8, clutch cover vent in dash 10, std cam cover vent in dash 8 and additional cam cover weld on in dash 10 - excessive? maybe, but never blew a seal / gasket ever.

[nightrider]

oil filler vent in dash 8,  additional cam cover weld on in dash 10

Having a hard time imagining these two, pics pretty please Gixer1460

Plus, has anyone tried a weld-on location in the top case? Some where above or behind the transmission i'm thinking.

[McLean Racing]

as stated above, for stock engines, probably no need but a must for tuned motors

on my nitrous bike i run a an10 breather from the oil filler cap and a modified breather cover with an8 which all terminate into a catch tank and in 3 seasons of racing it has never put so much as a drop of oil into the catch tank

[Gixer1460]

Having a hard time imagining these two, pics pretty please Gixer1460

Plus, has anyone tried a weld-on location in the top case? Some where above or behind the transmission i'm thinking.

Re the Weld-on Q - the red cap in the 3rd piccy was the dash 12 turbo oil drain line return - not into case but into clutch cover

Edited November 29, 2015 by Gixer1460
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