XB9R to Blast primary swap

[Bullettooth023]

So a few buddies who own 12's have done the 9 primary swap and after riding them I now want to do something similar to my 9. It got me thinking maybe a blast primary would work. Does anyone knows the gear ratio of a Blast compared to the 9? I've found several different numbers. The Blast numbers I found are (1.6:1, 1.676:1, 1.7) and the only 9 number I was able to find was (1.68:1). Has anyone ever done this before or think it could work? If i still owned my Blast I'd just try it myself...that being said does anyone have a willing donor

 

[loose1]

I think the blast is the same as a 9
Matt

 

[buellxb9rs]

I believe it it as well.

 

[loose1]

And I just remembered, the chain is narrower too.

 

[noone1569]

Mark, worst case scenario, you could probably have one of the custom sprocket manufacturers make a smaller diameter front sprocket for the 9 primary. We have a couple 12 donors they could use for bore size now. Chain may require some changes depending on how much smaller you went.

These guys get good reviews:

http://pmpsprockets.com/products