same specs but different rims..same size??
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From: sacramento ca
same specs but different rims..same size??
i have a question..might be noob but here it is anyways. If I bought say one set of brand X rims. size 18X9+30 offset. and another set of brand Y rims same size and offset will they(different brands) fit exactly the same?? Reason for this being running one set on one side and another set on the other side. Also, If i know how good brand X fits and it has the right stance I would like to duplicate the look just with another brand(brand Y). Maybe I have confused bit if anyone knows can ya help? thank!
If the wheel size and offset are the same, then the wheels will sit in the wheel well identically. The offset is the distance between the centerline of the wheel to the mounting face. A positive offset indicates that the mounting face sits outboard of the centerline. A wheel's width is measured by the bead width, not the overall width of the wheel, so you could have some difference there, a wheel could have additional material in the lip so the overall width could be greater. In actuality, I'm not sure how much variance from wheel-to-wheel there is in overall width for a given say 8" wide wheel.
What isn't easily expressed is the shape of the spokes, and how the wheel lips down near the outside edge to accomodate the valve stem hole. Obviously a wheel with outward curved spokes is going to offer much better brake caliper clearance than one with straight or inward curved spokes. So you can end up with 2 sets of wheels that have matching size and offset, and one set has no caliper interference, and the other does either due to spoke shape or the inner diameter of the wheel near the outside edge.
I guess this is why there's so many threads like "Will X Brand 17x8.5 in offset +30 fit?" No easy way to tell without just test fitting the wheel.
In fitting 15x7 +35 gravel wheels I ran into the problem in that the spokes offered plenty of clearance, but the ID of the wheel decreased quite a bit near the outside edge of the wheel, so I ended up having to run 10mm spacers giving me an effective offset of +25mm. It's not inconcievable that a wheel from a different manufacturer would've cleared with no spacer, or maybe only a 5mm spacer.
If wheel manufacturers wanted to make our lives easier, they'd post up dimensionally correct cross-sectional templates of their wheels in every size and offset they make in PDF format, and you could just cut one out of cardboard, and verify caliper clearance by setting it on your rotor hat and spinning it 360. You could also make sure there wasn't any interference with any suspension pieces by doing the same thing with the front wheels at full lock in both directions. Why this isn't common practice eludes me.
Check out this link: http://www.tirerack.com/wheels/tech/...jsp?techid=101, it makes it easier to visualize offset.
What isn't easily expressed is the shape of the spokes, and how the wheel lips down near the outside edge to accomodate the valve stem hole. Obviously a wheel with outward curved spokes is going to offer much better brake caliper clearance than one with straight or inward curved spokes. So you can end up with 2 sets of wheels that have matching size and offset, and one set has no caliper interference, and the other does either due to spoke shape or the inner diameter of the wheel near the outside edge.
I guess this is why there's so many threads like "Will X Brand 17x8.5 in offset +30 fit?" No easy way to tell without just test fitting the wheel.
In fitting 15x7 +35 gravel wheels I ran into the problem in that the spokes offered plenty of clearance, but the ID of the wheel decreased quite a bit near the outside edge of the wheel, so I ended up having to run 10mm spacers giving me an effective offset of +25mm. It's not inconcievable that a wheel from a different manufacturer would've cleared with no spacer, or maybe only a 5mm spacer.
If wheel manufacturers wanted to make our lives easier, they'd post up dimensionally correct cross-sectional templates of their wheels in every size and offset they make in PDF format, and you could just cut one out of cardboard, and verify caliper clearance by setting it on your rotor hat and spinning it 360. You could also make sure there wasn't any interference with any suspension pieces by doing the same thing with the front wheels at full lock in both directions. Why this isn't common practice eludes me.
Check out this link: http://www.tirerack.com/wheels/tech/...jsp?techid=101, it makes it easier to visualize offset.
