Crankcase evacuation

[Guest]

I run crankcase evac systems on all of my performance motors (dirt modified etc.) Wondering if my '78 gs1000 "Pro Street Bike" would benefit from that technology. Thanks

[Onthebar]

a bit more on crankcase evac

I run crankcase evac systems on all of my performance motors (dirt modified etc.) Wondering if my '78 gs1000 "Pro Street Bike" would benefit from that technology. Thanks

There are claims of horse power gains on race engines using these systems & the benefit of no breather mist in the engine compartment on my street car is great. I'd like both benefits for my GS, but limited space for mounting the one way check valve & it's spigot on the exhaust has me thinking that it may not be worth the trouble. Any info on this would be appreciated, gotta get off the fence. Thanks.

[rapidray]

Yes, they are a benefit but most now just use a vacuum pump to draw a bigger vacuum in the crankcase, allowing less ring tension & still getting ring seal, freeing up even more horsepower.
Ray.

[dorkburger]

After going the pods route on mine, I often wondered what to do with the vent on the top of the engine that went to the airbox. I ran a hose down to the bottom of the engine, then connected the shown pipe. Venturi effect pulls a vacuum. I confirmed this with a magnehelic gauge ( sensisive pressure gauge ) I dont recall how much vacuum it pulled, but it did pull a vacuum. Did it make a real world difference on an internally stock engine? None that I noticed....

[madmikeracing]

Back in the eighties on our old drag Bike I welded a bung into the narrow section of our V and H sidewinder Pipe for the crankcase evacuation system. Ran Lines to it, (Braided Stainless steel ) On dyno was supposed to give 4 horsepower or so at high rpm. I am not sure the Tech Officials approve of oil vapors venting from exhaust pipe ? Anyhow a vacuum pump would be the best . (Like Ray had said)

[Onthebar]

Thanks for the info, it's nice to look at it w/a better understanding. I'm on the last mock-up, trying to tie up loose ends before completion. I've raced dirt bikes, snowmobiles, karts, drag & dirt cars, I do a ton of performance work out of my business, mostly chassis work & components, but we touch all the bases.... I give you guys a lot of credit, this bike has been a big challenge. With all the time spent back-halfing it for car tire & all the frame mods, wheelie bar, pipe, seat pan & mounts to retain enough stuff to keep it streetable, it all has to come together this time or it gets shelved again, cause customers are already screamin. thanks again. I don't think I have room or probably need a pump, but curious how it would be driven.

[rapidray]

The vacuum pumps most common now are electric.
Ray.

[Onthebar]

You seem to be a wealth of "real world" knowledge & I appreciate your time. I went ahead & welded in the bung for my evac system, after all... nothing ventured...nothing gained. Thanks again.