15x10 vs 15x8

The inner edge of the rim is not moving, it's the tread of the tire that is moving (not changing size, just moving), because the tire is centered on the rim. If the rim is a different width, then the tread of the tire HAS to move in one direction or another.

You noted above that all you are doing is moving the sidewall in. That's correct, but you are doing it on BOTH SIDES, so the tread of the tire does move slightly towards the inner edge of the rim.

So you are saying that if I have a 1" wide rim, and a 10" wide rim (same backspace), with the same tire size, that the inner edge of the tread will be the same distance from the UCA on the 1" rim as the 10" rim?


If you didn't understand my hawaii analogy above, then I don't know of an easier way to explain it.

And your using of the words magical, and other phraseology, is starting to get on my nerves, especially since your point is incorrect

 

Here I drew a picture for you.

Both of these rims have zero backspacing, for simplicities sake. Both have 12.5" tread tires.

As you can see, in the setup on the left side (8" wide rim) the tread hangs over 2.25" on each side of the rim (therefore it hangs over 2.25" over the inner bead seat).

On the right setup (10" wide rim), the tread hangs over 1.25" on each side. (1.25" over the inner bead seat)

Therefore, on the 8" wide rim, the tires will in 1" closer to the UCA than on the 10" rims.

 

Look dude, the point of all of this is to help other people. If you want to contribute information, that's great. In fact, I encourage giving information back to others. But at the point when you're giving bad information and fail to recognize that more than 1 person is telling you your information is flawed helps no one. I work on wheels and tires everyday. I have worked on wheels and tires for over 6 years, and am very familiar with 1st gens, as my previous taco was a 2002. If you know so much about wheels and tires, perhaps you should go to work for a wheel and tire shop. Best of luck to you OP, and if you have anymore questions, feel free to PM me

 

look dude...i am helping by letting him know the rim width is not his problem. hes not rubbig on his sidewall he is rubbing with his TREAD. an 8 10 or 12 inchrim is not going to change that. im just making sure he doesnt waste money on afix that wont fix. and take it easy man.im not giving bad info YOU are.

as long as the BS is the same on both rims it is not going to do much but suck the sidewall in which will NOT change the width of the TREAD on his tire which is hitting his fenderwell. you are giving the misinformation. i am done. leave it alone.

I have worked with a rim that is actually 2 pieces and i have plenty of experience with this exact mindset you have. you would have to see it to believe it because i did.

 

Are you serious? Explain to me what part of my diagram didn't prove you wrong. Do you just not understand what we are trying to say here?

 

The tread width is not going to change...it will remain 12.5" wide....but it's position will move in 1" closer to the uca. That's what my diagram is showing. I'd like to see how you see it differently.

If he's rubbing on outside of the tread, moving to a 8" from a 10" rim may well cure the rub, because it moves the centerline of the tire in 1".

You can't just "suck the sidewall in" on one side only.

 

of this may be a a question that may help to help the understand some. what actually is backspaing and the offset?

 

Offset is how far the mounting point of the rim is from the rim centerpoint. Backspacing is the distance from the back edge of the rim to the mounting point.

This website helps explain it:

https://www.rsracing.com/tech-wheel.html

 

OP: Does the diagram I posted above make sense to you? We kind of got caught up in all this arguing, just wanted to make sure you were following....

 

yea it makes sense to me thank you for posting that up. i was just sitting back watching while yall were going back and forth.lol

 

so what do yall think would be the best thing for me to do with back spacing and offset or smaller tire . im going to get some ebiach coils which will give me close to an extra inch of lift that could probly help with some of the issue hopefully.

 

I'd see if the coils help anything first.