Changing Sprockets size and Belt??? Hard to find answer....

[Greerstyl]

Thanks for the help on this one guys:

Basically I would like to put the 70 rear tooth 1125r sprocket on my xb9sx and figure out what belt size I would need. Any ideas?

I have been searching feverishly through this and all the other forums, google etc. There are topics on it but it seems the answers aren't apparent.

I would like to change the sprocket size on my 2009 xb9sx without going to a chain. I really like the look of the belt and the way it feels. No complaints there. Just looking for more low end torque. Up the rear sprocket or down in the front.

I read that a couple different models of Buells carry different rear sprocket sizes. Here is what i understand so far.

xb9sx stock = 27 front, 65 rear
1125r = front?, 70 rear
1125cr = front?, 76 rear

i found this link but it dances around the subject:
http://www.buellxb.com/Buell-XB-For...rket-parts/Bigger-rear-sprocket-for-a-03-xb9r

Hopefully this post can work for anyone inquiring.

What are the front and rear sprocket options?

Do they all bolt\line up?

What belt sizes will work?

is there anything else that would have to be changed?

Thanks guys!

 

[captain chaos]

Changing ratios with a belt drive is a major pain, especially when you have a fixed tensioner like the Buell has. That's one of the reasons why chain conversions are popular.

Basically, you need 1 more tooth on your belt for every tooth you add to either pulley. The stock belt is an 1 1/8" wide 128 tooth belt with a 14mm pitch (distance between the centerline of 2 teeth. Adding 5 teeth to the rear means you'll need a 133 tooth belt. I don't know if one exists. 91(?)-03' Sportsters use the same belt as an XB so finding a place that makes belts for Sportster is probably your best bet. Also, 133 teeth may be a little tight since the dia. of the rear pully is bigger (from having more teeth) the angle from the front pully to the rear is going to be different. You may also have to convert to a non-fixed tensioner to make it work. I dunno for sure though, never tried it. This is all "theory".

Overall, I think it's going to be more of a headache than it worth. A chain conversion may be MUCH simpler, assuming you can still get the rear sprocket.

 

[Greerstyl]

Great info thanks I guess I was asking too much lol. Was hinge someone was like yeah here's the part numbers...

Anyone else do or try this?

 

[Loki]

Try this.

 

[Greerstyl]

Perfect Loki thanks alot. I like it! Anyone have one? How would that work captain?

Now I just need belt and sprocket.

Anyone know if the 1125r sprocket bolts up?

 

[loose1]

The rear one will.
HD uses a 133 and 135 x 1 1/8 belt. I'm looking for a 133 for my blast that has xb wheels and a cr pulley.
It's easy as long as you have an adjustable idler.
Matt

 

[captain chaos]

I've always liked the look of that free spirits tensioner. Very slick setup. I see no reason why it wouldn't work great other than it's in Europe and I have a hunch it would end up being very costly by the time you got one here in the states.

 

[lexhere27]

I have the free spirits tension on my build, works great. Google it and you'll find a few places that sell it.

 

[Greerstyl]

Ok and correct me if I am wrong but the 2003 xb9s looks to have a 72 belt and all right? Can I just swap to that setup?

And if not where can I get the 133 belt?

Thanks

 

[Greerstyl]

Is this what I am looking for?

http://badweatherbikers.com/buell/messages/20164/500161.html?1310335952

 

[Greerstyl]

any more help on this one?

What about just swapping to the 72 tooth rear of the 03?

 

[dmp0001]

I have thought about trying the xb9 primary swap but I hate swaping internals. What percent gear ratio change would I see from swaping the rear pully and belt to 70 or 76 teeth? How many teeth are on the stock CR belt?

 

[Greerstyl]

if you have a 12 i would do the primary. i have the 9 which i can wheelie the crao out of but i want to slow it down. like 5 mph wheelies. tends to stall a little

 

[Jerry C]

Will the rear sprocket off an XB12 work on a XB9, would the front sprocket need to be changed?

 

[loose1]

9's and 12's use the same final drive pulleys. Except the '02-'03 9's. They have their own drive system and can't be mixed with the older or newer Buells.
Matt

 

[crawfo]

Do you know what is different about the 02-03 9's loose?

 

[loose1]

The tooth design of the belt is different. It's smaller and weaker. That's why they went back to the old design. You can put the newer belt and pulley's on the early xb's.
Matt

 

[crawfo]

I remember reading it was good to switch out the pullys for a 2004+ but wasn't sure if the old sprokets would except the newer belt without problems

 

[twisted]

What about going with a smaller xbr pulley on a 1125r?