Why engine and sprocket differences by year?

[Scoobydude]

Been talking to some sportster owners and I'm getting a lot of different info on the spacing between the frame rails and the rear pulley. Why does this change from year to year?

I have a 2000 and I was wondering what mine is. I've got a bit of a basket case right now, but I threw the axle and everything on it together in a hardtail I have laying around, and my gap is slightly less than 1/16". It seemed a little closer, but I have all the spacers and in the correct t orientation.

If it matters to anyone I've found that an 06 is 3/8" and an 02 is .213"

[Sky]

Are you trying to compare rubber mount to solid mount frames?

[farmall]

The two frames don't match because no reason exists that they should as they are different frames for different bottom ends.

[JBinNC]

You are working with an aftermarket hardtail section or frame, and you are wondering about differences in measurements? You have more faith in the consistency of aftermarket parts than I do.

That said, your '00 and the '02 are the same series of chassis, but the '06 rubber mount is a whole different animule.

Jim