What fuel with Fast By Ferracci 12:1 high comp pistons?

[lwszabo]

my 95 M900 has the FBF 12:1 pistons, heavy duty studs, stage 2 jet kit, open airbox, ferracci slip-ons. What gas do you recommend running? I was thinking 93 octane.

[Speeddog]

W heads or V heads?

[lwszabo]

W heads or V heads?

I am not sure, how do I check?

[Speeddog]

Stamped on the side of the head, left hand side, next to the valve cover.

[lwszabo]

it has V2 stamped on the left side of the head.

[lwszabo]

also what is the differnece between v and w heads?

[lwszabo]

I sent you a pm

[Speeddog]

W heads have 750-sized valves and ports, and 750 cams.
Good for making low rpm torque, but that's about it.
They're not *awful*, as my Cagiva Gran Canyon has 'em, but they're disappointing.

More info here:

http://www.bikeboy.org/900equal.html

http://www.bikeboy.org/grancanyon.html

V2 heads are good.

As to the fuel, I'd say try the 89 and see how it likes it.
then try the 91, and see if it's any better.

Other folks here have done high-comp 900's, and I have not, so YMMV.

[Porsche Monkey]

I run 91 just to be on the safe side.  Its only a half a buck more to have some peace of mind.

[lwszabo]

W heads have 750-sized valves and ports, and 750 cams.
Good for making low rpm torque, but that's about it.
They're not *awful*, as my Cagiva Gran Canyon has 'em, but they're disappointing.

More info here:

http://www.bikeboy.org/900equal.html

http://www.bikeboy.org/grancanyon.html

V2 heads are good.
I always use 93 octane, it seems to be good when the bike is cold, and around 4500 rpm...but it all changes when I get into a city. the bike cuts out  abit! the bike only has 4500 miles, and is new to me!

As to the fuel, I'd say try the 89 and see how it likes it.
then try the 91, and see if it's any better.

Other folks here have done high-comp 900's, and I have not, so YMMV.

[lwszabo]

I was hoping it didn't need race fuel

[teddy037.2]

when I got my hi-comps, the consensus I got was that 11:1 was on the 'safer' side running w/92 octane e10 gas, which is the best we get here... if we didn't have any ethanol, I'd probably have gone w/12:1

[Duck-Stew]

You're likely going to need at least 91 octane.  If you had the W heads (with smaller cams and therefore more cylinder pressure), you may be in the realm of racing fuel.

[ducpainter]

You're likely going to need at least 91 octane.  If you had the W heads (with smaller cams and therefore more cylinder pressure), you may be in the realm of racing fuel.

[lwszabo]

sounds like i need High test! FBF has not returned my calls yet!