So I understand BCD/PCD, rim diameter, offset.
Now I have 2 questions
1 - Why does my wheel print say "7 1/2" inch rim width but my tape measure says 8.5" ?
2 - is centre bore relevant for modern vehicles?
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1. Where does it say 7 1/2? Is it "7 1/2 JJ"? Rim width is measured from inside the bead.
2. Very. These days it's the centre bore that holds the wheel, well, centred, as well as taking the weight. As opposed to the old days you'd make sure all the nuts were in their holes properly.
Edit, if I changed wheels to a later model rim on my old car, I'd have to use hub rings to take up the difference.
blakamin:
1. Where does it say 7 1/2?
Subaru stock wheel.
Engraved on the wheel "18x71/2J"
I just edited my first post.. It's measured from inside the beads.. So measuring from outside to outside will give you a larger number.
If you're looking at aftermarket rims, make sure they have the same or larger centre bore, and if larger, get hub rings.
Ah ok. Maybe I'll search wheel width for particular tyre width ... trying to source a set of rims coz I managed to buckle 2 wheels over a large unsighted pothole ...
joker97:
Ah ok. Maybe I'll search wheel width for particular tyre width ... trying to source a set of rims coz I managed to buckle 2 wheels over a large unsighted pothole ...
Most online tyre shops have a calculator for that biz.
What size tyres?
I know how you feel... I did the same in my last car. That's when I found out Fulton Hogan do roads here in Adelaide
Or a Suby forum...
I have this guide for my car, it'll give you a basic idea, but mainly aimed at BMW owners.
http://www.meeknet.co.uk/e31/timms_bmw_wheel_and_tyre_page.htm
EDIT: Actually, if you look down the bottom, the e31 - e32 bit is pretty much normal tyre widths.
225 45 18 ...
thinking of 225 50 17 for more room for the next pothole ... !
don't want wider (need clearance for snow chains)
225's will fit on a 7.5in rim. The profile (50) will change your speedo and possibly your guard clearance, but not by much. It seems Subaru fit fairly comfy tyres as standard!
It came with Ferrari tyres (Potenza RE050A) ... rigid sidewalls ... wasn't comfortable at all! Maybe I'll look out for holes once I find wheels and tyres ... what tyres do you run on your beemer?
I have 235/60 16s on it.. The ride is very comfy
On the one I wrecked the rims, 235 45 17.
those sound like formula 1 tyres
“We’ve arranged a society based on science and technology, in which nobody understands anything about science technology. Carl Sagan 1996
"vibration at 75-95kph" It could be anything :(
So it disappears at 110kph?
How many Ks has it done?
Maybe start another thread to get more participation ...
“We’ve arranged a society based on science and technology, in which nobody understands anything about science technology. Carl Sagan 1996
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