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.
W heads or V heads?
Quote from: Speeddog on May 28, 2009, 02:36:52 PM
W heads or V heads?
I am not sure, how do I check?
Stamped on the side of the head, left hand side, next to the valve cover.
it has V2 stamped on the left side of the head.
also what is the differnece between v and w heads?
I sent you a pm
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/900equal.html)
http://www.bikeboy.org/grancanyon.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.
I run 91 just to be on the safe side. Its only a half a buck more to have some peace of mind.
Quote from: Speeddog on May 28, 2009, 03:04:36 PM
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/900equal.html)
http://www.bikeboy.org/grancanyon.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.
I was hoping it didn't need race fuel
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
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.
Quote from: Duck-Stew on May 28, 2009, 06:12:53 PM
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.
;D
sounds like i need High test! FBF has not returned my calls yet! :P
Quote from: lwszabo on May 29, 2009, 04:11:02 AM
sounds like i need High test! FBF has not returned my calls yet! :P
You
may also need to retard the timing.
Quote from: ducpainter on May 29, 2009, 05:42:55 AM
You may also need to retard the timing.
Is this hard to do? I would think FBF would set everything up right!?!
I put J+E 11.1:1 pistons in my 900SS and with the timing fully retarded I still get some ping on high-test, but I'm a bit lean too.
Quote from: lwszabo on May 29, 2009, 05:46:39 AM
Is this hard to do? I would think FBF would set everything up right!?!
It's not that difficult,but requires removing the left cover...and yes you would assume that they did.
Ride it with high test and if it pings badly we'll go from there.
No pinging, but it has full exhaust and an open airbox. I wonder if I should get a colsed airbox cover. :( it was tuned with all the mods, so we will see!
Quote from: lwszabo on May 29, 2009, 06:29:27 AM
No pinging, but it has full exhaust and an open airbox. I wonder if I should get a colsed airbox cover. :( it was tuned with all the mods, so we will see!
If it was tuned with an open box leave it alone.
You can try mid grade, but I'm pretty sure your set up needs high test.
Run premium and get 1.1 modules or the newer Chec box. It's unlikely you really have 12:1, most are around 11.2:1 or 11.5:1, although true 12:1 can be had and still run fine on pump gas.
Quote from: Norm on May 29, 2009, 07:12:09 AM
Run premium and get 1.1 modules or the newer Chec box. It's unlikely you really have 12:1, most are around 11.2:1 or 11.5:1, although true 12:1 can be had and still run fine on pump gas.
I never thought of that, I am sure there is really no true drop in 12:1 kit! I have had no problem. Thnaks . luke
Quote from: lwszabo on May 29, 2009, 04:11:02 AM
FBF has not returned my calls yet! :P
Don't hold your breath.... [roll]
Quote from: ducpainter on May 29, 2009, 05:42:55 AM
You may also need to retard the timing.
Ha ha ha he said retard [laugh]