Hello. I'd like to know if I can maintain either my gear ratio or speedometer accuracy while switching to 17" rims. I would like aluminum rims for weight reduction (among other things), and I figured someone might recommend a set and some tires to match. Where do I start looking?

http://www.miata.net/garage/tirecalcold.html

16" rims are lighter than 17" on average.

Steel rims are lighter than aluminum rims of the same size.

Ride quality and cornering will be better with 16" than 17" assuming you select the right tire.

I don't see any logic in your reasons for the choice in 17".

Will


Steel rims are lighter than aluminum rims of the same size. ???

Yes, they are. Steel is stronger than aluminum, so there'* less of it. That'* why most of us with slicks prefer steel wheels.

I talked to someone at Pep Boys today, and he said that aluminum rims of a larger size would actually provide better handling and such. He based this on saying that the rubber displaced by the larger rim is heavier than the rim that displaces it.

However, it seems that 16" steel rims are actually lighter than 17" aluminum rims, and I sincerely hope tire rubber is lighter than rim steel. If so, I'm good with 16" rims. However, aren't my rims, the gold, crossing lace-like ones, pretty heavy because of the sheer amount of steel? I'm not into looks as much as I am into staying light and such.

Radomir, your crosslace rims are ALUMINUM. Not steel. Steel wheels would be lighter, but the crosslace are known here to be the lightest production aluminum wheel on Bonnevilles.

The guy at pepboys is wrong. For better handling, you have to allow your sidewall to flex in order to keep the contact patch on the road. Your suspension rates are calculated to take this factor into account with 16" rims.

2000'* are 'tuned' in the suspension rates to allow for the shorter sidewall on the 17'*.

radomirthegreat, I have a speedo-recalibration unit from Intense that I'd be willing to sell you for cheap. That way regardless of size of tire/rim you can adjust your speedo.
PM me if you're interested.

Go for a rim that allows you to run a wider tire, while still not "rubbing". I believe you should be able to run a 235 or maybe a 245 without any "modding". I believe 255'* would require some modding or maynot fit at all. Others here will know better then I.

As for which rim is light/heavier.... if you're picking a performance rim, they manufacture normally has the weight of the rim listed. Just compare that to how much your current rim weighs (without the tire of course).

I don't think a calibrator is really necessary if the right tires are chosen in the first place. But in this case, judging by what I think he'* trying to say, once he realizes his crosslaces are actually aluminum, and the lightest production bonneville wheels available, he'll probably be happy with them.

Awesome posts! That is very cool. I figured 17s would be good because they have available for them 2455017 tires, and then I could have wider tires. Well, I'll just enjoy my stock rims unless something amazingly better comes up. Thanks!