Bicycle Mechanics - litespeed ocoee to 69er conversion-what forks?

Any help would be appreciated.Its a 17 inch bike with 2004 sid rock shox.I was looking at white industries carbon fiber but not sure if I should get 445 or 465 mm .How do I measure and calculate for the right size in order to keep the geometry close?Thanks

Is the 69er the bike with a 26" wheel one end and a 29" one the other?

yes, i want to put a 29 inch tire on the front .

Put this Salsa 26" fork on my Ocoee('99), it is a good one...replaced the old sprung suspension on mine to rigid.

They have 26 and 29 models.

http://salsacycles.com/components/cromoto_grande_29er


bill

26" rim diameter = 559mm
29" rim diameter = 622mm

So assuming you use the same size tires, you're looking at a 31.5mm increase in rim radius. So I would measure the axle-to-crown (ATC) distance on your current setup and try to get a fork with a ATC of 31.5mm less than that. Make sure to measure when you're actually on the bike to take the sag of the fork into account.

Realize that a few mm is not going to matter. In fact, an inch or two in each direction is probably fine depending whether you want the handling to be "quicker" or "slower."

I'm guessing the bike is kinda on the XC side and designed for 440-ish axle-crown. Measure your Sid's ATC and if it's in that neighborhood and you like the current geo I'd go for the 445.