15" 126 tire size recommendation

[Robert W. Roe]

I have heard that 215-65R15 was a stock size but I am also considering the 205-60R15 sizes for my 126. Mine has the newer style wheels and I want to put Michelin MXV4's on the car.

Anyone have experience with either of these size tires? Tirerack's web site suggests using the 205-60R15's.

Thanks in advance,

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Robert W. Roe
1984 300SD 165K miles

[Lee Scheeler]

Hmm...if stock size was 215/65/15 then 205/60/15 is 5.1% shorter overall rolling radius. They have always recommended staying within 3% of OEM rolling radius. 215/60/15 is within 1.9% of 205/60/15 and 215/65/14 is very close (.6% and 1.3%) of both of the 15" sizes. If OEM width was 215, then I would stay with at least that.
You may want to recheck both your OEM size and (based on that) Tirerack's recommendation. I may be missing something but I'm pretty sure 205/60/15 is not a good fit for 215/65/15.

In any case, the Mich MXV4 is the best touring tire you can buy. Whatever size you choose, you can't go wrong with that michelin.

Hope this helps...Lee

[Robert W. Roe]

Lee, thanks for the reply. My owners manual only lists 195/70-R14. I've seen different sizes on various 126's of later years, but I'm assuming that the final drive ratio is different as well on these. Tirerack did only suggest the 205/60R15 in the +1 sizing in the 15" wheel.

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Robert W. Roe
1984 300SD 165K miles

Original size for 15" W126 is 205/65. I use 225/60-15 and they look great on the original 15 x 7 in wheels. 205's look too narrow for such a big car. Anyway, the stated size is not all. Contact patch width of different tires with the same size(diameter) varies. It would be a good idea to comparison shop before you buy. Some people like the rounded edge look(where the tire meets the road) and others like the square edge look.

[Robert W. Roe]

With the 225/60's is your speedometer accurate? Also, is there any rubbing or other clearance problem?

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Robert W. Roe
1984 300SD 165K miles

[Lee Scheeler]

Robert,
If your car's OEM was 195/70/14, then the 205/60/15 is nearly a perfect fit. (0.3% shorter overall, 1/10th the acceptable variance) The 225/60/15 would be 3.6% taller overall and hence not a good idea to cross fit. 225/60/14 is almost a perfect fit, but that is with 14" wheels. By that logic, 225/55/15 is a 100% perfect fit for OEM of 195/70/14. I would check with Tirerack as far as fittment of either 205/60/15 or the 225/55/15.

As far as rounded or square shouldered tires. That generally depends on the type of tire. Touring tires will be more rounded, a max performance tire like the MXX3 or P-Zero will be very square edged. Since you plan on using Energy MXV4's you will be looking at something with a very rounded profile.

Hope this helps...Lee

[Robert W. Roe]

I have 205/65/15's on the car now. What does the 3% affect? My car doesn't have ABS. I'm thinking that the speedometer calibration will be off somewhat, but am I in danger of rubbing something with larger tires, say the 225/60/15? How far off would the 215/60/15 be?
I like the idea of longer range/better fuel economy by increasing the effective final drive ratio with bigger tires. The only Michelin tire in 225/55/15 that I found on Tirerack's web page is the MXM. Are these better for high-speed handling than the MXV? I remember transforming my 108 280SE with H rated Michelin's, but I'm not sure if they were touring or performance tires ... was there an MXV (or MXS perhaps) in the late 1970's?

Also, one thing strange that I noticed: my wheel bolts on the back of the car stick out more than the ones on the front. They are the 15x7 wheels from a 1986+ 126. Is there any reason to be concerned about having the wrong bolts?

I had them swapped from another 126 in exchange for the stock 14" alloys that came with the car. The wheels have the "KleanWheels" dust shields inside them. I plan to remove these as soon as the paint on my wheels is a month old.

Robert W. Roe
1984 300SD 165K miles




[This message has been edited by Robert W. Roe (edited 08-19-1999).]

[Lee Scheeler]

If you go beyond the "3% rule" you are in danger of rubbing as a result of larger overall rolling radius or wider section width. Some cars/models are more touchy than others but it is usually safe to stay within 3% variance of OEM.
The michelin Pilot HX MXM is listed as a touring tire but is actually more of a sporting tire. Put a set on the 500E and they are far more grippy than the XGT Z4's they replaced. (with a better ride to boot) By the numbers the treadwear should not be as good with the MXM's vs the XGT's but have not had the tires long enough to comment on that.

If you are not having any rubbing from too long bolts then the sticking out should just be a cosmetic problem. You may want to call Tirerack and discuss the specifics of fittment with them.

Hope this helps...Lee