Wheel width

[Kev@KAM]

This may be a stupid question but when buying alloys and the manufacturer lists the width as 7j is that the bead seat width or overall width?

 

[JamesBryan]

Bead seat to bead seat.

 

[JamesBryan]

Same as the diameter is measured to the bead seat floor not the outer rim edge.

 

[Kev@KAM]

Right. I need to order wider then lol
I hate custom parts!

 

[JamesBryan]

There won't be that much in it i'd imagine though, i mean, how thick is the lip of a rim on most wheels...

Might be best to double check with them.

 

[Kev@KAM]

True. Just the tyre I need to use looks overtyred on a 7" rim so need to go a little bigger to sort

 

[JamesBryan]

What tyre is it?

Race tyre manufacturers usually list an optimal rim width.

 

[Kev@KAM]

Pirelli Trofeo R. Their sizing is pretty broad but most competitors are using 7" rims. I think we can get a bit more from the tyres though with a bit more width...
Pirelli themselves say the 7" is not really ideal but no-one runs wider rims (mainly as you have to go custom)

 

[PhillipM]

Bead width, wheel itself is usually about 1/2" wider.

 

[JamesBryan]

Just had a look at the Trofeo R and 205/45/17 rim spec is 6.5j min, 7j optimal and 7,5j max.

I'm guessing you're on a 17" wheel?

 

[JamesBryan]

 

[Kev@KAM]

15" rims I think its 205/50r15 off the top of my head. The other 225 width one we tested but its like a van tyre and needs an 9" rim I'd say

 

[JamesBryan]

Lol they don't seem to list that spec ?

 

[Kev@KAM]

Its not on their common sizing guide, but you can scroll down for smaller fitments

 

[Darryl_1983]

I was looking at ultralite F1 alloys the other day. These come in 15 X 7.5J. and 6.5kg. but they are a copy, design wise and I'm not sure how strong they are.