Just an FYI for anyone wondering. I put 225/50 Kumho Ecsta Supra 712's on the RSX yesterday, and they fit, no rubbing on sharp turns or anything. Maybe everyone alreaedy knows this, but I didn't, so I was a bit worried till I test drove it. So if anyone didn't know, now you do.

and DANG what an improvement over those 205 michelin oil slicks that used to be on there.

 

two words:

tread squirm.

 

It's not an issue so far, and I don't see it being an issue anywhere but a tight autox, and even then, the difference would not be dramatic. But thanks for your two words.

 

Not so much tread squirm as it is sidewall deflection.

But the OEM tires suck so bad that I doubt you'll notice.

 

interesting.

 

Mine stock are 215's. Were they 205's in the previous models before '05? They seem to grip pretty well to me so far. Not the best tire but far from the worst.

 

Yes, 05's come with the 17" 21lb wheels with 215/45/17's

02-04 came with 16" 16lb wheels with 205/55/16's

You pay for the 17" bling

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jolt-tsp &raquo;</TD></TR><TR><TD CLASS="quote"> I put 225/50 Kumho Ecsta Supra 712's on the RSX yesterday, and they fit, no rubbing on sharp turns or anything. </TD></TR></TABLE>

How do they look? I've got 225/50/16 Kumho MX on 16X7's and the sidewall bulges quite a bit.

 

I'll see if I can get a pic tonight. The bulge isn't as dramatic as I expected. I still have the crap stocker michelins on the back, and they don't look mismatched.

 

712's are not a wide tire. If those were S03's or something, you'd definitely notice a bulge.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by kung fu grip &raquo;</TD></TR><TR><TD CLASS="quote">two words:

tread squirm.</TD></TR></TABLE>

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Todd00 &raquo;</TD></TR><TR><TD CLASS="quote">Not so much tread squirm as it is sidewall deflection.

But the OEM tires suck so bad that I doubt you'll notice.</TD></TR></TABLE>

What do these things mean?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Todd00 &raquo;</TD></TR><TR><TD CLASS="quote">712's are not a wide tire. If those were S03's or something, you'd definitely notice a bulge.</TD></TR></TABLE>

Ya, I've noticed Azenis or some other tires seem up to an inch wider. I didn't take a pic, it got dark. If you look at the stock tire(205), there is about 15mm between the tire and the edge of the wheel. The 712's (225) go all the way to the edge. Still, I'd say the tread of the tire is no wider than the wheel, except maybe 5mm. It's hardly noticable.

 

todd had it right.

essentially, because the tire is wider than the rim, the sidewall has a tendency to deflect (shift or roll) under cornering. it can leave the driver with a vagueness in steering feel under cornering and transition.

think of it like this: imagine wearing shoes that are a bit too big for your feet. you can lace them up and they work fine, but they tend to shift around a little when you run or cut back.

it's not dangerous, per se.

a wider rim matched with the tire gives the car a better 'platform' or 'plant' when cornering.

i've put 225 width hoosiers on 5.5" stock miata wheels. stiff sidewalls in that case. wasn't bad, but a lot of the "cripsness" and feel was gone.

 

sorry, let me add:

tread squirm is really the tread of your tire deflecting (sideways). the tread blocks are taller when they are newer, so the 'squirm' a bit while cornering.

the only real danger to putting too wide of a tire on a rim is that if the side wall is too soft, you *could* pop it off the bead if you corner too hard.

sorry about the double posts...it's kinda early...coffee hasn't kicked in yet.

 

Hmm, so 225/50 is still too wide on a 7" wide wheel? I have a set of Kosei's 16x7.5" which I specifically bought to run 225/50 (though found a cheap set of Azenis so I mounted them on). I was thinking of selling them and just settling for 16x7, but maybe I should reconsider...

 

technically, yes. but a 225 is happier on a 7"" rim over a 6". the azenis also has a stiffer sidewall, so the deflection won't be as bad.

two main reasons i kept with a 15" wheel was a) tire choices/options/prices b) weight.