How much shorter of a stroke is the 9 compared to the 12?

[sak1782]

Im thinking of picking up a project bike, and building a slightly higher reving turbo bike over the winter. I remember reading that the 9's had a shorter stroke, and there for can rev a bit higher, more safely than the longer stroke 1203.
Anyone know much about this?

 

[rockerphotographer]

I've never ridden one, but I've read the same. It seems the racers tend to like the 9's better as well. Thinking about getting one myself to play around with

Just wondering though, would you have to replace with stronger internals to be able to run a turbo?

 

[sak1782]

There are already forged kits out for these bikes, so thats not an issue. I was actually thinking of doing a 9SX, with a 1250 kit, and running a few lbs of boost. Fabrication of the kit is not a big deal, and I would just run it rich, while dialing back fuel till i get a good AFR and no knock/ping. I dont want to build a crazy monster like my turbo busa was, but something with alittle more would be nice

Ive also thought about talking to a friend of mine to see if we could fab up a trans casing for a Baker 6 speed.
http://www.bakerdrivetrain.com/xl/index.htm

I have too much time on my hands down here in the hotel...LOL

 

[captain chaos]

1203cc stroke: 3.813"
984cc stroke: 3.125"
so yes, it is a LOT shorter.
The limiting factor for revs becomes the valvetrain though.

I've owned both a 9 and a 12 and personally I like the freer revving (and smoother) nature of the 9 better. someday I will probably have another Buell but it will be a 9 with a 1050 big-bore on it. IMHO, the 9 is the better motor and the 1050 kit (along with some other goodies) would just perfect it.