[3181]

I would like to take a minute to talk about backspacing. Its my personal opinion that backspacing is one of those things that is a little hard to nail down at first, and is often overlooked by unsuspecting noobs. YUP,its been covered, but i dont think its been covered very well. It took me a very long time to figure out what BS i wanted, so i thought it may be helpful to cover this thuroughly for any newcomers that dont know what BS is, or how to choose the right BS. Sooo... i would like to open up discussion on the pros and cons of different backspacing amounts and put down some info on helping people CHOOSE the right backspacing for them.

Backspacing Tech:

What is Backspacing (BS)?: For a good explanation click here and see the "backspacing" section

Factory XJ BS is: ??(someone help me out here. this is one question that comes up ALOT and not too many people know the answer)

Common BS numbers: Most people purchase rims with backspacing between 3.5" and 4.5". Remember, the LOWER the number, the more the rim will "stick out"

Why not just keep stock BS?: There are a few reasons why one might want rims without stock BS. They are..
-Tires that are ??" wide will rub on the lower control arm when the wheel is cranked
-Looks. Plain and simple. While i prefer function over fashion, no one wants to build an ugly rig. Some prefer more wheel stickout, some prefer less.
-why else? to prevent fender rubbing?

Other BS considerations: It has been said that a rim with very little backspacing (2.75" for example) can have a negative effect on bearings. Since the mounting surface offset from the center fo the rim, torque is applied to the knuckles. I have yet to hear ANYONE gripe about this, for the most part... it seems to be a non-issue.

OK, thats what i have so far... lets open it up for discussion. why did you choose the backspacing you did for your junk? what were the factors? what would you change about your decision and why? think something i said is stupid or ridiculous then lets hear it!

when we gather some more info i will edit this original post and try to keep the most pertinent info up top. have you ever seen anyone get this excited about rim backspacing?

-jm

 

[1572]

just to add to the why you dont want stock bs list

your rear tires will rub on the inner fenderwell when flexing

there will never be a magic number becuase its gonna depend on tire size, tire width, axle width, and suspension height. but this thread is a good idea, but i would like to add to another part of the rim the width. keep it skinny if you wheel and air down, youll be much less likely to pop a bead with a skinnier rimm.

 

[2719]

I beleive the factory

was 5.25
And I have heard that 31 10.50 tires will be the first to rub the lower control arms with stock

I can't talk from experience other than with my 235/75s which rubbed like mad with a budget boost but I think I also have 4.5

. Not positive though

 

[3946]

I have 31X10.5 15's on aluminum rims. Also a 3" procomp lift. They only rub the fender flares a little at tight turn radii. I don't know what the backspacing is on them. They do not contact the control arms.

 

[2793]

I thought the bs on the stock 7" wide steel wheels was at something like 4.5". I can doublecheck, though, since I have the stockers laying in the garage. I went 3.5" on my new 8" wide ones to widen the stance and bring the tires out a little more for clearance on the LCA. I did have to trim the air dam in the front, though, since they rubbed there with the new offset. Also, at least around my area, it seems to be the case that the smaller the offset, the farther out the tires go, and the friendlier the DOT cops want to get with you by pulling you over.