[M.O.Ther]

Re: Sportster wheel question

Rubone is correct in what he writes. There is one other difference between the pre '70 rims and the '70 and newer aluminum rims and that's the bead seat profile. The earlier ones are all WM profile. The '70's ones are CM profile.

The CM profile rims are made for use with Goodyear Taper Bead Base tires. I think it was an attempt on the part of Harley and Goodyear to corner a part of the motorcycle tire market.

It doesn't mean you can't use them. I have an 18" steel CM profile rim on the back of my '96 Sportster, with a Continental SuperTwin 120/90-18 tire. And am about to lace up a 19" disc brake front aluminum rim to a mid star hub to use on the back of my Pan project with a 4.00 x 19 Sears copy of a Pirelli MT53.

The rear Sportster 18" rims as well as both styles of the front 19" rims are 2.50 at the bead seat, so the width is OK to use a front on the rear. You want to use the one for the disc brake though, because it's drilled for a smaller diameter hub. The 18" will be part number 43008-70, and the 19" will be part number 42998-74.

Here's a link to a tech piece that has more details.

http://www.jockeyjournal.com/forum/showthread.php?t=22085

 

[M.O.Ther]

Re: Sportster wheel question

ok, say i use a disc brake 19 wheel as a donor. will the spokes lace to the midstar hub or will i need custom spokes ?

You will need custom spokes. But you can get chromed steel ones pretty cheap, or buy the good Buchanon's stainless for around $100. It's a common size.

 

[M.O.Ther]

Maybe this will help a little. The differences aren't much. This is from an Avon tire catalog. They don't show the CM profile because, like it says, they don't recommend...