OMG stock V stack vs Factory Pro must see

torque my friend torque.

Graves make better power in the midrange...

:fact :beer :beer

I'm so confused with the whole Graves vrs Factory Pro thing.

I have the Graves, FWIW.

Ram air on the 04/05 R1 seems to starve #2/3 cylinders of air so the Graves design equals the air flow.:beer :beer

Actually...

Factory helped Graves design their stacks. I had the Graves on my 2002 R1, but am going to try the Factory set for the '04.

I think Marc's got a winner here!

Wheatman said:

Graves make better power in the midrange...

:fact :beer :beer

Click to expand...

Better than stock or better than the Factory Pro? Or both?

Marcs great to deal with. Always real informative....

:bow I can testify to that. I've got the Factory stacks in my 04! Really smooths out the power band...! :thumbup

Anyone have a true comparison on the two. I'm in the same situation. Which one to get.

Lestat77 said:

Anyone have a true comparison on the two. I'm in the same situation. Which one to get.

Click to expand...

I second that. Any side by side comparisons???

That dyno unfortunately doesn't help at all. You cannot compare a standard bike to a bike with exhaust AND stacks, to tell anything on the effect of the stacks themselves.
We need a dyno showing the difference "before/after"

Take care

Juerg

Juerg said:

That dyno unfortunately doesn't help at all. You cannot compare a standard bike to a bike with exhaust AND stacks, to tell anything on the effect of the stacks themselves.
We need a dyno showing the difference "before/after"

Take care

Juerg

Click to expand...

where did you get exhaust out of that post?

You have two different designs. I think the Factory pro stacks would help alot more with midrange and you would lose alot more with the top end. The graves you will gain some mid range, but only lose a little in the top end. Guess, it depends on what your really looking for.
From what I understand velocity stacks don't produce more HP but move the power band in the RPM range. Shorter stacks are better for top end power and longer stacks are better for midrange/low end. Yamaha actually increased the midrange on their 05 R6's by making the middle stacks longer. Just like the Graves set up, but they made up for the top end loss by making the throttle bodies bigger. Still would be nice to see a back to back comparison on the dyno.

Do they make those for the carb. bikes?

LDHR1 said:

where did you get exhaust out of that post?

Click to expand...

:iamwithst

the dyno shows stock, graves stacks, factory stacks, and factory stacks with bmc filter

atleast thast what i got out of it........:dunno

Both the graphs with the yrd is Yoshimura Racing Development.