Tyres for SLK

[cen]

I will shortly require new shoes for the SLK320 which is currently fitted from new 205x55x16 front and 225x55x16 rear. In fairness the tyres Mich Pilot HX have now covered 29,000 miles with the front starting to become illegal on the outer edges. The rear are still good for a couple of thousand which I find extremely good.

I intend purchasing Mich's again however, what problems could I encounter if I fitted 225 on the front instead of 205? That is of course exept the price which is considerable checking online prices.

[pentoman]

If you fit bigger tyres on the front I think it will affect the rolling circumference. That means the speed sensors will pick up incorrect speeds for the front wheels, which will confuse the ABS/ESP systems so you might well have their error lights coming on and those functions not working.

[trickywoo]

You really don't want to be doing that.

[blueyes]

To go to 225 you need to drop to 50 series to keep the same rolling radius:

205/55/r16 converts to 225/50/r16.

MB have shod your car with that size tyre for a very good reason and spent lots of money in R&D working out the optimum size for handling, ride, braking and cornering. Also in the back of your handbook will be a list of sizes that they recommend (TUV tested). Stray from those recommendations and it could be a way out for your insurance in the event of an accident.

In the 171 SLK they even have a special MO Pirelli tyre, with a softer compound, for the rear. They know what they're doing: I changed to Goodyear F1's and the handling was diabolical in any temp below 10c. So bad in fact I took them off after 3000 miles and binned them.

Stick with what MB recommend.

[cen]

Thanks guys, I didn't think altering the width by 20mm would make any difference. One positive thing is that 205 are so very much cheaper