Wheel Terminology Questions.

TTEPHOTOS

Organizer
Hey guys first thread! Looking at wheels for an inbound 17 JKU, they are not going to go on right away like some other things but I do want to at least figure out what ones I want. I have 4 in mind and as a general rule could someone explain the backspace rule? I will be running the OME 2" heavy lift, the wheels will be going on 35x12.5R17 Nitto Ridge Grapplers when everything is said and done. Wanting to make sure I won't be rubbing or having any issues as far as the back space goes. and am also kinda hoping to rule out at leaste one of these to make the choice easier!

Fuel - Trophy D551
17x8.5, -6 Offset, 4.5 BS
17x8.5, 6 Offset , 5 BS
Decent looking wheels, not sure how I feel about the Anthracite, love the Forged version of them but I need to be able to drive on the road.

Black Rhino - Armory
17x9.5, -18 Offset,4.5 BS
Love these and if I am able will probably run them, but info is pretty limited, they are listed here as having the 5x127s but everywhere else they seems to be strictly 6 lug.

Method Racing - 311 VEX
17x8.5, 0 Offset, 4.75 BS
Probably my runner up to the Black Rhinos mostly due to Mickey Thompsons below no longer offering the black ring and it not being removable for easy paint. Different method of measuring throws me off though. Assuming Backspacing.

Mickey Thompson - Classic Baja Lock
17x9, -12 Offset, 4.5 backsacing
Nice set of wheels and a great company, wish they still did the blacked out ones though.


Appears I am unable to post links yet, originally had hot linked the wheels to their respective spec pages, sorry in advance. If anyone has and praise or hate for any of these I would love to hear it as well, and photos are always appreciated if you are running them, even better if your body color is black!
 
Last edited:

TTEPHOTOS

Organizer
Hope this helps.

Appreciate it, So the more negative the offset and the less backspace the better for us correct? (Widens the stance and keeps the tires farther from shocks, inner well etc?) Any kind of rule of thumb for a minimum?
 

Hilldweller

SE Expedition Society
You should be good with 4.5" to 5.2" backpspacing. When they get to talking about offsets and whatnot, my eyes glaze over and I start to zone off.
 

rubicon91

Explorer
TTEPHOTOS I just got rid of my stock rubi wheels and upgraded to some level 8 trackers. They are 17x8.5 with a 4.5 BS and -6 Offset. I gained about 2.5 inches of width over stock. I am still using the stock tires as well. The first pic is about the only one i have that is close to show how the stock wheels were tucked in. The second and third are last week after I put the new wheels on. The tires now stick out a tab past the fenders as you can see if you zoom in on pic 3. Huge difference in the stance now with the wider rim. This is what the discount tire rep said and he was spot on. As far as stance goes, the front lip of the 17x8.5 ET-6 Tracker will sit 2.50-inches further out towards the fender when compared to where the front lip of the factory 17x7.5 ET+45 Rubicon wheels sit now.
Hope this helps some for you.
 

Attachments

  • 20170304_133956_resized.jpg
    20170304_133956_resized.jpg
    632.5 KB · Views: 9
  • 20170407_121213_resized.jpg
    20170407_121213_resized.jpg
    605.5 KB · Views: 10
  • 20170407_121229_resized.jpg
    20170407_121229_resized.jpg
    607.1 KB · Views: 11

TTEPHOTOS

Organizer
What I have learned

So guys, I read the article posted above and here is what I gathered from it.


Backspacing: Measurment from the Inner edge to the wheel mount face.

  • B= 1/2W+0+1/2" Is the equation you can use to determine a wheels offset.
    B= Backspace
    W= Width of the wheel
    O= Wheels Offset

  • More=More Less=Less
  • A general rule for lifted vehicles is that a backspace less than 5" should put you in the clear however different lift kits can effect this.


Offset: The distance from the center of a wheel to the mount face.

  • O=(W/2)-B
    O= Offset
    W=Width in mm
    B=Backspacing in mm

  • The Lower your offset the farther out the wheel will sit due to the distance from the inner "face" of the wheel to the mount being less. So again with offset and with backspace less or lower is better.
  • The Lower offset will contribute to a wider "stance" and some setups may even require a wheel with an offset of zero or a negative offset. If you reduce the inner clearance too much or push the wheel out too far, the tire might rub or not fit at all.



All of this really only helps you if your are just changing the wheel but keeping the same tire though.
Some useful calculators for offset and tire sizing can be found on 1010 tires website (still unable to post links sorry).
WeldWheels also has calculators for converting backspace to offset or offset to backspace.
I am still looking for an overall equation to determine Inner clearance if someone has one or can point me in the right direction.
 
Last edited:

TTEPHOTOS

Organizer
Solution!

UPDATE:

Found a killer website that should serve any needs we have. Will They Fit. Awesome side by side comparison, and even a nice visualization. Info I pulled for the Ridge Grapplers run on the Black Rhino Armory wheels.
CompareExistingNew
Diamete802.8mm877mm
Circumference2522.1mm2755.2mm
Poke51.3mm138.7mm
Inset139.3mm102.7mm
Speedo Error0-8.46%
@30MPH3027.46
@60MPH6054.92
Ride Height Gain037.1mm
Arch Gap Loss037.1mm

"Compared to your existing wheel, this new wheel will have an inner rim which is 36.6mm further away from the suspension strut. The outer rim will poke out 87.4mm more than before. "
 

Attachments

  • wheelimage.gif
    wheelimage.gif
    7.8 KB · Views: 66

TTEPHOTOS

Organizer
TTEPHOTOS I just got rid of my stock rubi wheels and upgraded to some level 8 trackers. They are 17x8.5 with a 4.5 BS and -6 Offset. I gained about 2.5 inches of width over stock. I am still using the stock tires as well. The first pic is about the only one i have that is close to show how the stock wheels were tucked in. The second and third are last week after I put the new wheels on. The tires now stick out a tab past the fenders as you can see if you zoom in on pic 3. Huge difference in the stance now with the wider rim. This is what the discount tire rep said and he was spot on. As far as stance goes, the front lip of the 17x8.5 ET-6 Tracker will sit 2.50-inches further out towards the fender when compared to where the front lip of the factory 17x7.5 ET+45 Rubicon wheels sit now.
Hope this helps some for you.

Thanks for the visual. Wheels look great! Think if I can find some in stock I will be putting on the Black Rhinos, will give me 3.5 wider look and an extra inch an half away from the struts!
 

kenaero

Observer
Remember with less backspacing your steering will change as well. Will become more squirrelly as backspacing goes goes down, this may require more toe-in to compensate. Thats why AEV uses a 5.2 inch backspace on an 8.5 inch rim. My Pro-comps are in that 5 inch range and do not rub with a 3.5 inch lift. Plus strain on your ball joints etc go way up, so keep an eye out for that. Of course that just another excuse to UPGRADE!!!! love me some good upgrades.
 

Forum statistics

Threads
189,927
Messages
2,922,317
Members
233,083
Latest member
Off Road Vagabond
Top