Changing Tire Size

[2SmartNM]

Has anyone used a different tire than came with the Smart? Is there any alternative to the Continental 155/60R15 for the front wheels?

[Muckquomp]

I would like to add the same question but with more spicifics. What narrower rear tire size substitute can I use? I want to increase my gas mileage. I thougt the rears were 60s and the front 75s?

[bull8042]

Not really an answer to your questions, but something to think about nonetheless. Going to a narrower tire should/could increase your mileage a little, and may help with driving in the snow. However, handling will also be adversely affected.
I just put 195/45R-16 on the front and 215/40R-16 on the rear of my Brabus. Granted, I went from the factory tires to Yokohama S.Drives in addition to the size change. But my handling improved quite a bit. It is now much more responsive, more "go cart-ish" for lack of a better description. Also, the wind-buffeting is reduced noticeably, not eliminated, but reduced.
So, the handling is something else to consider in addition to your mileage concerns when you start thinking about a tire change.
If you really want to improve your mileage, find a station that sells fuel without ethanol. That should easily improve your mileage 10 - 15%. Marinas are usually a good source.

[kennyrayandersen]

once a car gets a certain mileage, incremental improvements mean less. The savings from 40 mpg to 50 mpg is only a couple hundred bucks a year. That's why, generally, hybrids are such a bad deal. A Prius is several grand more than a Corolla, but basically the same sized car -- you will never make up the fuel savings from the initial cost.

So, as stated , you might pick up an mpg or slightly more by going to a narrow (preferably high-pressure) tire, but you'd save $30/year and have worse handling -- it makes the fuel savings appear to be 'not worth it'.

[Huronlad]

Originally Posted by 2SmartNM

Has anyone used a different tire than came with the Smart? Is there any alternative to the Continental 155/60R15 for the front wheels?

Kumho makes smart size tires, performance might not be quite as good, I think they have a softer sidewall.

[Huronlad]

Originally Posted by Muckquomp

I would like to add the same question but with more spicifics. What narrower rear tire size substitute can I use? I want to increase my gas mileage. I thougt the rears were 60s and the front 75s?

Continental Ecocontact tires can be bought in 145/65R15 size. They however will not mount to the rear wheels, you would need 4 front wheels. If you are not traveling much over 60 MPH, the 145's would be perfectly fine. Handling and braking performance will be reduced.

[bull8042]

Originally Posted by kennyrayandersen

once a car gets a certain mileage, incremental improvements mean less. The savings from 40 mpg to 50 mpg is only a couple hundred bucks a year. That's why, generally, hybrids are such a bad deal. A Prius is several grand more than a Corolla, but basically the same sized car -- you will never make up the fuel savings from the initial cost.

So, as stated , you might pick up an mpg or slightly more by going to a narrow (preferably high-pressure) tire, but you'd save $30/year and have worse handling -- it makes the fuel savings appear to be 'not worth it'.

Kenny stated it a bit more eloquently than I did, but, er....yeah, what he said.