I've been contemplating getting a set of these to free up parasitic drivetrain loss and free up some horsepower...Rick's claims it sheds 1 lb 10.1 oz of rotating mass from the pulleys...
bear in mind these are not underdrive pulleys, they are stock dimensions, just much lighter.

Have any of you tried these? Butt dyno results?? Real dyno results??

Ever since my dyno appointment I've been bitten by the bug to free-up / add horsepower

 

"Fongu" from Ottawa, Canada, got these some years ago. I don't know if he still has them. You might want to PM him a link to this thread so he might comment. I do recall when riding with him, that he mentioned he actually did a calculation and came up with a real number for the "effective" gain. And he seemed to indicate he could feel it in the butt dyno.

 

The is roughly 60 sets out in the field at this point. So they are not a new idea. I am sure someone can post thier impressions. I know that serveral of the current GB members already own a set and are in it for a differant color.

 

I like to think of them as an addition to my lightened drive train. Pullies, flywheel, wheels. it all adds up enough to walk an AP2

 

im with you boooo the ap2 grrrrrrrrr

 

I've been running them for about 3 years with no difficulties. They definately allow the engine to wind up quicker.

 

is it a noticable gain? i had a crank udp pulley on my old car that weighed alot less and it made a very nice difference.

 

does our OEM crank pullie have a dampener?

 

Yes, it is a dampener.

 

I would be surprised if 1lb less rotational weight translated to the wheels, but if it does it's an upgrade I will do and probably need to do before boost so I don't need to tune it in later