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I needed these for my back as the ride is pretty harsh on these with the OEM rubber even set at the recommended tire pressures. I got these set at 34F and 36R now. Feeling good so far.
I've got to say that 34/36 sounds like a **LOT** of pressure. That's a pretty big tire for such a lightweight car, and if you get the pressures too high without enough weight on it, the tire can't work like it was designed to.

I had a Miata for five years and ran 185/55-15's on it, and settled on 30 front and 32 rear pressures on high performance all-seasons with a relatively stock suspension. This was on a 2150 pound car with 50/50 weight distribution, and I'm one that tends to like the higher end of the tire pressure spectrum. Others with the same Miata, and relatively same suspension and tires ran a couple of PSI lower, which gave probably the highest ultimate grip level. The pressures I ran didn't offer as much grip but gave a wider plateau of a bit less grip. Any pressure higher and the tire just got harsh, had much reduced grip, and beat up the suspension.

So just a suggestion to give some lower pressures a try. Even if you don't corner at the limit, you'll notice better performance in reduced braking distances, especially in the wet. If I were to run 185's on my 2100 pound ED, I'd probably again be in the 30-32 PSI range. On a 1700 pound car with that width tire, I'd probably be around 28 PSI.
 

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^^^Thanks. I normally run high pressures for mpg & efficiency. Maybe I'll try dropping the pressure a tad more a couple lbs a time and see where I settle on.
 

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^^^Thanks. I normally run high pressures for mpg & efficiency. Maybe I'll try dropping the pressure a tad more a couple lbs a time and see where I settle on.
Undoubtedly, rolling resistance goes down with more inflation pressure, but so does tire life. What you might save in gas will be hard pressed to overcome extra tire costs, and even if it does you are losing out on grip. Here's a couple of charts:

rolling resistance versus inflation pressure:



tire life versus inflation pressure:



Of course, that being said, tire life or maximum grip isn't always the primary factor. I do lots of things deliberate that don't maximize tire life nor fuel efficiency (like alignment specifications). The pressures you choose have to work for what you want.
 

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Drove 195/17 40 Yokohama S-drives all around on Genius Darwins all summer, very stable well behaved car. The cap was how the car handled on the Watkins Glen race track. Super handling. That tire combo is superb in the rain but useless in the snow so I'll play it out this fall. Then the over the winter revamp will have a much more aggressive looking tire package on the current car.

I think it is headed to the pampered show and shine circuit next spring and summer. A set of Genius Darwins, 215/50 15s will hit the rear and 205/50 15s on the front. I am looking for a beefier side wall for a more muscular look. The next Smart will inherit the 195/40 17s and will be made for the track. On a trailer pulled to the track by the show car........... ahhhhhhh let a man dream.....

A fantasy photo shop of my spring 2019 dream.........

 

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Yes today I paid my dues and have become a member of the All fours, rotate your tire club.
2015 Passion style package edition.
205/50R15 Nitto Neogen.
15x6.5 Genius Newton Gun Metal wheels.
My Mercedes wheel centers fit like a dream.
Installed New TPMS
New Lug bolts.
And happy as a pig in S&$# over the ride quality and handling verses the original setup of 165/60R15 on front and 195/50R15 on the rear. Absolutely no rubbing front or rear, speed bumps not an issue, high speed cornering the only noticeable aspect is better handling. No more drifting in lane driving at speed. No spacers required due to the +25mm offset of the wheels.
62659

62660
 

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Yes today I paid my dues and have become a member of the All fours, rotate your tire club.
2015 Passion style package edition.
205/50R15 Nitto Neogen.
15x6.5 Genius Newton Gun Metal wheels.
My Mercedes wheel centers fit like a dream.
Installed New TPMS
New Lug bolts.
And happy as a pig in S&$# over the ride quality and handling verses the original setup of 165/60R15 on front and 195/50R15 on the rear. Absolutely no rubbing front or rear, speed bumps not an issue, high speed cornering the only noticeable aspect is better handling. No more drifting in lane driving at speed. No spacers required due to the +25mm offset of the wheels.
View attachment 62659
View attachment 62660
What effect does this have on the Speedo?
 

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This is for "Members" of this "Club" ONLY.

I would just like to see 'who' and 'how many' have made a switch to put the same size tires/wheels on the front AND back?

They don't have to be OEM wheels/tires, just as long as you have the same size at all four corners.

I know there's already a thread or two 'discussing' this. THIS IS NOT THAT THREAD. I'm only looking as to who and why.....PLEASE no discussions or opinions from those who are NOT a member of this "Club".

SIMPLY list WHAT 'mod' you made (OEM or Aftermarket, wheel and tire size, brand...etc) and WHY you did it.

Feel free to post pics TOO!:D
.
Thank You! :)
Yes, my 2008 smart car has the OEM rear wheels all the way around. I run 195/15/50 Yokahama tires. Better ride
 

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What effect does this have on the Speedo?
As far as the rear are concerned it’s a wash with no increase in overall diameter. Previously I was running 195/50R15 on the rear and increased the width only to a 205/50R15.
The fronts are a slight difference as I went from a 165/60R15 to a 205/50R15 with a total diameter difference of 22.08 inches for the 165/60 to a 23.07 inches for the 205/50 which converts to 1.2 percent difference in diameter between the two.
The speedometer change at best is negligible and has not affected anything like the ABS/ Traction control. The speedometer changes at speed is as follows: 20 MPH 0.24 MPH difference and at 65 it’s a 0.74 MPH difference. Not enough to make a noticeable change IMHO, compared to the benefits of now having a car that’s a pleasure to drive with handling that is stable verses that lane drifting and over steering I used to deal with
Paula
 

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Ok thanks. I want to get all 4 tires the same AND get the speedometer corrected. Currently, at top speed for my 2016 ED, I am OVER-reporting my speed by 4 or 5 MPH. I want to get bigger tires to take care of this. There's a thread somewhere that I bookmarked that tells me which tires to get, but I can't find it right now.
 

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Ok thanks. I want to get all 4 tires the same AND get the speedometer corrected. Currently, at top speed for my 2016 ED, I am OVER-reporting my speed by 4 or 5 MPH. I want to get bigger tires to take care of this. There's a thread somewhere that I bookmarked that tells me which tires to get, but I can't find it right now.
Your welcome,
What I have researched is you want to stay as close as possible to the original diameter the car came with. You can look on the door plate and find the size listed if you’re not sure. I’m going to guess the fronts were 60s like most of the smarties and the rears were 50s.
My original intentions were to go with what George (1983JRZ3W) is running on his Brabas which are 215/35R17 on 7.5 inch wheels which would have brought me to the closest OEM diameter and in my opinion art the best setup, but the roads up here in New York are terrible and I needed that extra rubber between the road and the wheel that the 2015/50 gave.
Paula
 

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Yesterday, I bought one OEM rear 9-spoke aluminum alloy wheel from eBay for $117 shipped, and I'm about to buy the 2nd one from WheelerShip.com for $144 shipped.

Question: Can I re-use the TPMS's from the existing front alloy wheels? If so, do the tires need to be deflated/removed from the front wheels to do so?
 

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Yesterday, I bought one OEM rear 9-spoke aluminum alloy wheel from eBay for $117 shipped, and I'm about to buy the 2nd one from WheelerShip.com for $144 shipped.

Question: Can I re-use the TPMS's from the existing front alloy wheels? If so, do the tires need to be deflated/removed from the front wheels to do so?
I’m going to go out on the limb here and say yes you can reuse them if they are not too old where as the battery is going to fail. I believe the batteries are good for about 5-7 years. Mine on my second set of wheels are six years old and still work fine. The new ones I purchased off EBay Im having issues with them that I have to correct.
You only need to deflate the tire and break the bead on the stem side to remove them without having to take the entire tire off the wheel. But in either case they are installed from the inside out.
There are some interesting videos on YouTube showing how this can be accomplished.
Keep us posted we care!
Paula
 

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I think I'm just going to order 2 (or 4) new ones on Amazon so I can leave my 2 original front wheels intact and inflated, and use one of them as a spare.
 

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Got my new front wheels mounted this week!

With 195/55R-15 Riken Raptor VR tires on all 4 wheels!

Part of my motivation for doing this, on top of being able to rotate tires, was to correct the optimistic speedometer that was off by 5mph and was capping my top speed in my 2016 Electric Drive to 78mph (even though it read 83mph). Now I can go 81mph (still shows 83mph)!

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