Taller gearing on '09 XB12?

Buellxb Forum

Help Support Buellxb Forum:

Miami78

Well-known member
Joined
Dec 7, 2009
Messages
1,677
Is there any way to get a little taller gearing on an '09 xb12Ss while keeping the belt?

With my proper tune I constantly feel like I'm going to fly off the back of the bike during hard acceleration and I go through the gears very quickly...would like to try a little taller gearing for lower rpm's at cruising speed (at the sacrifice of acceleration), but I don't want to do a chain conversion...want to keep the belt. Is that possible?
 
You might be able to put the Xb12 primary gearing on there I don't know why you wouldn't be able to you can put the 9's on a 12 for more low end grunt.
 
Um, I have xb12 primary gearing already (it's an '09 xb12ss)...I'd like some taller gearing if possible...
 
up one tooth on the front, and down a few on the rear so that the same aspect ratio is maintined between the pulleys to keep the same belt tight.
you'll still have the speedo/odo error. dunno if a jap bike 'speedo healer' will do the trick. maybe power commander/ecmspy could change it.
http://www.americansportbike.com/shoponline/ccp0-prodshow/5470.html

a primary gearing kit sounds alot easier, but i don't see an 11% Primary gearing increase Kit for the 08+ XB12 listed on thier site. maybe some harley tranny parts can be interchanged.

or you can run a dry, open primary. i seen pics on teh interwebz of a belt driven primary with a dry clutch on an XB back in the day. havent seen any others since, so i presume it's not easy/cheap/worth it.
 
Thanks Matt! Guess I need to figure out how many teeth I have on each currently...
 
Ha, helps to crack open the manual...27 teeth up front, 65 teeth on the rear.
 
ASB has a 29 tooth front sprocket, wonder if it'll work with the stock belt and stock rear sprocket...I emailed Al to see if he has any input.
 
If you went up 2 on the front pulley did'nt change the rear sprocket wouldn't that put too much tension on the belt?

My belt seems tight enough already.

Maybe the FreeSpirits belt tesioner could help?
 
Don't know...I do have the free spirits belt tensioner, that should be able to take up some of that extra tension shouldn't it?
 
the xb9 kits use stock xb 12 primary chain and sprocket. there is no alternative parts for hte 12.

my lady had the conversion on her 9. made it a lot slower off hte mark, and yeah a cruisier top speed. was too cruiser like for my liking. eventually we changed to stock for her.

two points here. first... she said she wouldnt ever go back. was not as responsive or fun as hte bike is now (original trim) and second hte 12 chain was stretched quite a lot for only 15000klms. i am thinking cause of hte push to keep it in the rev range.

dont think you could swap a larger front sprocket with out changing hte diametre of hte rear smaller... would probably have to find something custom to do this anyway... but if you didnt change the diametres of hte sproketc repsectively,hen obviouslyt he belt is not going to stretch the extra.
 
and nillo... wouldnt one up on the front and one down on the rear make it launch fasternad top speed slower? the front would spin lower for more rear revolution.

i would think that for more top speed and cruisier acceleration, that it would be down in front and up in rear? could be wrong...
 
and nillo... wouldnt one up on the front and one down on the rear make it launch fasternad top speed slower? the front would spin lower for more rear revolution.

i would think that for more top speed and cruisier acceleration, that it would be down in front and up in rear? could be wrong...

Bass Ackwords.

Larger front, smaller rear = slower acceleration and higher top speed.

Smaller front, larger rear = quicker accel and lowered top speed.

~Mike.....
 
Back
Top