Parris crank mod

[raden]

I know this has been discussed before,and all the pros an cons why it wont/will work, but,has anyone ever actually rode or seen a bike with this mod sense it has been around for a while now?

[scalejockey]

We did this back in the 80s' to jet skis. Pure placebo effect!

[cwtoyota]

Is this the one with the swirl marks for "turbine" effect cut into the crank wheels?

If so, I read a test several years back that showed ZERO conclusive gains/losses from this mod.

[deelong4002]

I looked into their website, and the whole thing looks pretty sketchy. I'd have to say this is a scam.

[ncc]

The theory and idea would actually work had the machine the crank the entire gap between the small lines they did.

for it to actually move a significant amount of air it would need more displacement than the small grooves they do. It basically would "calvitate", or just have a small barrier of dead air it was cutting through as it spins.

If it were machined in a way that actually had "paddles" with sizable gaps to catch and push the air, it should add significant increase in power.

[stockrappy]

i think the best thing u could do is give them a call and just talk to them about it.

[s14 2510s]

On there web page the power gain they state is at a different elivation. If your going to state a power gain do it on the same dyno in close to the same conditions.