I need to get my geometry right on my racebike. When I bought it, it had used up Dragon SCs on it and is set up for that tire. I'm now using different tires (BT002s, DCs, etc.). What I want to know is where to measure to and from and what the right baseline ride heights are with a Penske shock.

Basically I want to know a dimension, like from the subframe to the ground so I can get the right ride height. I believe the front is pretty close but I don't know where to start there either because all the tires have different circumferences. Any knowlegable racers who can help me or point me to a website that can? Thanks.

By the way, it's a 2000, not sure if there is a difference.

The best suggestion is to check with the track side vendor for the brand of tires you are running. they can usually point you towards a racer that will have a bike that is set up that you can get some baseline numbers from.

personally, when i set up a bike, i measure from the bottom of the lower triple clamp to the top of the front axle to set my baseline. then i use a caliper to determine and set the amount of fork tubes that extend above the top triple. when installing a new shock, i measure from eyelet to eyelet and set length before installing. from there, i measure from the top of the rear axle straight up to a fixed point on the tail of the bike and adjust from there. once i have a setup that works, i adjust ride height for the changes in radius of the tires. also, i try to maintain some consistency and i dont change tires unless i have time to actually test them and dial the bike in for them. i keep a detailed notebook with my measurements and associated laptimes and comments so that i can reference them when making changes.

overall, you are looking for a setup that provides stability at speed while still maintaining manuverability. you get one at the expense of the other and you have to decide where your happy medium is.

good luck