Backspacing, what is it?????

I keep reading about tires/rims and backspacing. What is backspacing? I can`t find an answer in searching.

I'm sure there is someone with more info on this but backspacing it the distance in width from the center section of the wheel to the back edge.

I was going to try to do an ascii diagram, but just did a quick google search and found this:

http://www.yuccaman.com/jeep/backspac.html

-Copperhead

Thank you, now all this wheel talk makes some sense.

copperhead said:

I'm sure there is someone with more info on this but backspacing it the distance in width from the center section of the wheel to the back edge.

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Yup, looks like:


Don't forget that less backspacing means the wheel mounting surface will be closer to the back edge of the rim. 0" backspacing would mean a flush-mounted back of the wheel...

If a rim has less backspacing, does it have less strength?? It would seem that if the center of the rim (part that bolts to the axle) is centered within the rims outer body the stronger it would be. If so why not space it out using wheel spacers or some other way?

a lot of people would rather not use spacers for obivous reasons, like when u add one inch of space via wheel spacer, you add torque on the origonal studs (Force X Lever Arm = Torque) and efectively weaken them. However i havent heard any war stories from a friend who uses them to stuff 33" on her TJ with a 2" BB, so i guess theyre working for her. here is a little more info on spacers that i found using the "search" button
http://www.naxja.org/forum/showthread.php?t=33746&highlight=wheel+spacers

good wheelin to ya

BAMCHEROKEE88 said:

If a rim has less backspacing, does it have less strength?? It would seem that if the center of the rim (part that bolts to the axle) is centered within the rims outer body the stronger it would be. If so why not space it out using wheel spacers or some other way?

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Strength issues? Not that I'm aware of. When I perused the rim catelogs I didn't see any indication that rims with less backspacing are weaker, at least as far as the rim's specs are concerned. For backspacing, there's usually around a two inch variation available for a given rim. I don't think it makes much of a difference in strength as long as the rim was properly designed.

As for the spacers, some states outlaw their use. There are well built spacers and then there are cheap, risky spacers. Besides the legal issue, one reason why you don't see more spacers is because of their cost.

Is there a way to get back spacing by just putting a rubber or metal "spacer" on the hub before placing the tire on it to torque it down?

Is the benefit of backspacing that in full turns there is less change of tire contact with suspension components?

Cottontail said:

Is there a way to get back spacing by just putting a rubber or metal "spacer" on the hub before placing the tire on it to torque it down?

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Absolutely not! There are nice billet aluminum wheel spacers (www.performancewheel.com) on the market for this application. Use anything else and you run a very large risk of endangering yourself and others on the road. As for the billet aluminum spacer, check with your state on the legality of using them.

Cottontail said:

Is the benefit of backspacing that in full turns there is less change of tire contact with suspension components?

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Yes. Less backspacing places the rim further from the vehicle so that the tire doesn't rub against control arms and such. Perhaps equally important is that as you lift your vehicle higher, less backspaced rims give your Jeep a wider stance, which offers better stability.