17" Wheels. Any regrets?

[NukleoN]

Hi there,

I've got the ball-rolling on some Xtatic Mass 17" wheels with 195/40 fronts and 215/35 rear Yokohama S-Drive tires. The Mass wheels in black with the red stripe look simply amazing to me, but I am a bit bothered by the fact that there is basically zero technical information on Xtatik's site about these wheels and it's the weekend so there's nobody I can talk to at Xtatik.

I assume the Xtatik Mass wheels are made of aluminum, but nowhere on the site does it actually mention what they're made of or how much they weigh. The site (a nice flash design btw) does mention that the manufacturing process is used in aluminum applications, but that still doesn't directly tell me what the wheels are made of. My skeptical mind screams, are they hiding something or was this an oversight? Are we all to assume modern-days wheels can only be aluminum unless otherwise specified? Perhaps a reasonable assumption, but I hate to assume anything.

I've read nearly every relevant thread about wheels at SCOA, and I am well-aware of unsprung weight as it relates to vehicles and have read the technical back-and-forth regarding unsprung mass with regard to stock vs. 16" and 17" wheels. My question is, is this concern enough to stall my purchase process or am I over-thinking it? Is my Smart gonna be a hard-to-steer slug during parking maneuvers with noticably worse acceleration with 17" wheels?

In real-world driving, how did the change from stock to 17" wheels/tires feel in the Smart Car? Anecdotal evidence might suffice to allay my fears a bit here. Any noticeable slowing of acceleration?

I realize the bigger/wider wheels might be more stable at speed, but I don't want to make a slow car considerably slower, if that's the result. Having never driven a Smart in anything other than stock form, all I have is the tech info I've read (mostly speculation and solid theory) and then my own imagination of how it would be to drive the Smart with 17's.

So, any input would be great, especially from anyone here who's actually driven a Smart with the Xtatik Mass wheels. I want to hear the good, bad and the ugly!

Thanks a lot.

[WhiteNBlack08]

I will be following this thread with great interest, since I am considering a similar upgrade(only I plan on using the Genius wheels). If you go to Tirerack.com, it will give you all the technical specs for the OE vs S drive tires. One note, a 225/35 might suit you better on the rear. The 215/35 is actually smaller in diameter than the 195/40. Comparing tires, you are going to add close to an inch OD vs OE tires, and about 6 lbs more per tire than OE. But, the really curious thing is if you look at rotations per mile, which is what will affect speedometer calibration, and final drive(which will affect acceleration). The 225/35 S drive is within 3 rpm's of the OE tire, so it should not affect driveability or speedo calibration(0.3% difference). Obviously there will be some affect, due to increased rotational mass, and more surface friction due to wider tires, but I'd also really like to hear from people who have done the switch, how did it affect performace and mileage?

[cowancom]

#1-The stock tires on the smart are "low roll resitance" ,in english this means they are hard as rocks and NEVER "grab the road". Here in Florida where it rains every afternoon in the summer the stock tires run on top of the water. It's called hydroplaning and made the car more than a handfull to drive in the wet.
With the 17" rims and real tires the car it is much more stable and much safer to drive. When we first put the new shoes on the car it was much slower 0-60 and did not feel as nimble in parking situations. After living with this for about 5 months stupid (me) finally looked at the side of the tires. After riding around with 35lbs in each tire, stupid (me) put 45lbs in each tire. Side wall says 50lbs. Road around with a 148 degree road ,doing 70mph the tires never went over 48lbs of pressure ,so I feel thats ok for summer. Have I said I LOVE the Orange electronics tire pressure monitor system? Now the smart has it's zippy feel back and is back to being a breeze to park.
Amazing when you put the proper pressure in your tires.

[SmartChip]

NukleoN, I just swiched over to set of Genius Darwin wheels and Yokohama S-drive tires. Wheels are195/40/17 front and 225/35/17 rear.These tire sizes were recommended by Genius,Thefront rims are 6.5" wide and the rears are 7.5" wide. Genius also said to run the same pressure as the stock tires, 29 front and 36 rear. I've only had them on for a little over a week. I now thoroughly enjoy driving my Smart now. The tire change has totally changed how the car feels on the road. All of the "hunting, wobbling and "feeling light" problems are gone. The car feels planted and sticky, giving a feeling of much more confidence while driving in wet or dry conditions.I feel this is THE best and most necessary mod that I have madeto date. I hope this helps you with your decision.Cheerz, SmartChip

[NukleoN]

Thanks guys, all of these 'seat of the pants' comparisons help a lot! Keep 'em coming!

I like reading about the exact wheels people got and how the ride compared to stock, good or bad! I checked out the Schmidt 16" wheels but the price is too high and I can't get into the styles on offer.

[jwight]

Glad somebody mentioned hydroplaning; while fitting wider tires might be a good thing on dry roads, those same tires might increase the risk of hydroplaning:

Hydroplaning: The Role Tires Play

Hydroplaning happens when one or more tires is lifted from the road by a wedge of water that gets trapped in front of and under a tire as the vehicle drives through water. Hydroplaning most frequently occurs during heavy rainstorms when water creates puddles on the highway or expressway. In addition to the accompanying splash and scaring the heck out of the driver, hydroplaning typically causes the steering wheel to jerk and the vehicle to abruptly pull towards the puddle.

The speed at which a tire hydroplanes is a function of water depth, vehicle speed, vehicle weight, tire width, tread depth and tread design. It depends on how much water has to be removed, how much weight is pressing down on the tires and how efficient the tread design is at evacuating water. While deeper water, higher speeds, lighter vehicles, wider tires, less tread depth and less efficient tread designs will cause tires to hydroplane at lower speeds; all tires will be forced to hydroplane at some speed.

As a rule, tread design affects hydroplaning resistance at high speeds and in deep water. Tread compound affects wet traction at lower speeds or in shallow water.

Directional tread designs (sometimes called Unidirectional tread designs) are frequently used on tires intended to better resist hydroplaning. Their multiple tread grooves are aligned in a repeating "V" shape to increase the tire’s ability to channel water from between the tire’s footprint and the road. Somewhat like the vanes of a water pump continually pushing water in one direction through the engine, the grooves of a directional tire are designed to push water in one direction through the tire (forward on an angle to the sides). Directional tread designs are especially helpful in increasing hydroplaning resistance when relatively wide Plus Two, Plus Three or Plus Four tire and wheel applications result in fitting a much wider tire to a vehicle than its Original Equipment size.

Tire Tech Information - Hydroplaning: The Role Tires Play

There are a couple of formulas floating around for (very roughly) predicting the hydroplaning speed of a tire: 9 (or 10.35) x the square root of tire pressure. Bottom line: wider tires, less tread depth, lower air pressure all increase the danger of hydroplaning.

[John_H]

And yet the complaint is the smaller stock tires are more subject to hydroplaning? I don't understand.

[jwight]

Originally Posted by John_H

And yet the complaint is the smaller stock tires are more subject to hydroplaning? I don't understand.

I don't either; all else being equal, narrower tires hydroplane at a higher speed than wider tires.

[SmartMadness]

Originally Posted by NukleoN

Hi there,

I've got the ball-rolling on some Xtatic Mass 17" wheels with 195/40 fronts and 215/35 rear Yokohama S-Drive tires. The Mass wheels in black with the red stripe look simply amazing to me, but I am a bit bothered by the fact that there is basically zero technical information on Xtatik's site about these wheels and it's the weekend so there's nobody I can talk to at Xtatik.

I assume the Xtatik Mass wheels are made of aluminum, but nowhere on the site does it actually mention what they're made of or how much they weigh. The site (a nice flash design btw) does mention that the manufacturing process is used in aluminum applications, but that still doesn't directly tell me what the wheels are made of. My skeptical mind screams, are they hiding something or was this an oversight? Are we all to assume modern-days wheels can only be aluminum unless otherwise specified? Perhaps a reasonable assumption, but I hate to assume anything.

I've read nearly every relevant thread about wheels at SCOA, and I am well-aware of unsprung weight as it relates to vehicles and have read the technical back-and-forth regarding unsprung mass with regard to stock vs. 16" and 17" wheels. My question is, is this concern enough to stall my purchase process or am I over-thinking it? Is my Smart gonna be a hard-to-steer slug during parking maneuvers with noticably worse acceleration with 17" wheels?

In real-world driving, how did the change from stock to 17" wheels/tires feel in the Smart Car? Anecdotal evidence might suffice to allay my fears a bit here. Any noticeable slowing of acceleration?

I realize the bigger/wider wheels might be more stable at speed, but I don't want to make a slow car considerably slower, if that's the result. Having never driven a Smart in anything other than stock form, all I have is the tech info I've read (mostly speculation and solid theory) and then my own imagination of how it would be to drive the Smart with 17's.

So, any input would be great, especially from anyone here who's actually driven a Smart with the Xtatik Mass wheels. I want to hear the good, bad and the ugly!

Thanks a lot.

Nucleon,

I believe the wheel material is the same as all the other wheels in this range.

The finish on the wheels is nice and since you are nearby you can always swing by our shop and check out the wheels in person before we mount everything up for you.

We have these and all others in stock so you can see them for yourself and not have to rely on pics.

As far as the ride... We have never had anyone complain. Everyone that upgraded to larger wheels has loved the improvement in the ride.

We have a couple smarts at our shop that have larger wheels and you can always swing by and take a test drive first.

Boris

[babybenz]

when u go to 17s it simply means ur going for looks definatly not ride quality. also it takes a little hit in mpgs. one i am not one for ride quality and did not by my smart for the mpg so they suit my needs also go with a 225 in the rear