Wheels, Rims, and Tires

[Don]

Yes, the wheels are available . . . . for about $475 each

The rear tire size *should be* 205/45-16 as that is an identical size (in overall circumference) to our stock 175/60-15 . . . . but I *think* the Euro cars (which are smaller BTW) all came with 175/55-15's and if so, their 195/45-16 would be a closer match to those. The 175/50-16 they used for the front is the closest you can get to matching the circumference of the stock tire (there is no smaller 16 inch tire commonly available) and since it's 3 sizes wider, it should go a long way toward helping with everyday understeer, though when pressed to the limits of adhesion, it's definitely still going to understeer a bunch, because the rear tires are also 3 sizes wider . . . . but you'll be having lots more fun in the corners before the dreaded understeer raises it's ugly head than we are now :mrgreen:

Plus . . . . those wheels/tires just look damn cool on the car, IMO

My 14 inch 'solution' is also using 175 tires for the front and 195's for the rear BTW

Don

 

[Llecentaur]

Then if I have understood the basics, it would mean 16-5.5"-ET 34 for all 4 wheels, 175 all around, playing with tire ratios to get the right diameter...

I guess with these different sizes, a solution allowing rotation of wheels is not plausible unless we know for sure that speedometer is on the back wheel and then aim to match front tyres to the rear ones.

Don, is the issue of modding the hub to fit the front wheels very difficult to do ?

Thanks

 

[Don]

If you were buying 4 new Work wheels like they did, you just order the pair for the front with a larger hub bore and no modding would be necessary. Order all 4 with the larger bore if you want to be able to rotate tires . . . . it won't hurt a thing if the bore is too big on the rear

But, if you want to make rear wheels fit the front, you could simply grind away the interfering lip. Easy enough to pop the front studs out of the hub, grind it flush and then pull the studs back in using an open ended lugnut which you can purchase at any auto parts store

It would be nice to have 4 equal sized tires (so you can rotate them) and if I were going for that, I think I'd use either 185/55-15's on either 5 or 5.5 inch wheels or the 175/50-16's on 5.5 inch wheels like Rinspeed did - You KNOW for sure the latter will work . . . . I think the 15's would too, but don't hold me to it

I think I'd prefer a split arrangement with slightly more meat on the rear, which would mean a 175/195 combo in order to keep the gear ratio the same

Your Rinspeed contact should be able to tell you if the speedo maintains it's accuracy when using their combination - If it does, the speedo input is from the rear of the car, because their 175/50's on the front have a much greater circumference than the 145/65-15's they replaced. Their speedo would be off a bunch if the input is from the front wheels

Don

 

[melloyello]

I did even more playing around with the car this afternoon - I *thought* I had found a good solution. A set of four, 175/50-16's mounted on 2007 - 11 Honda Fit 16 x 6 alloys. The tires are within 1% of the correct diameter for the rear and should easily fit the front too, assuming the proper wheel. I even found me a *perfect* set of the Honda wheels for cheap - $330 plus shipping

So, before I pulled the trigger, I went back to measuring what *should* fit by mounting other 4 x 100 alloys I have laying around. Sad to say, There is no way any 6 inch wide wheel of suitable (or even unsuitable) offset will fit the front end of this car . . . . period!

I *think* the Rinspeed car is using 175/50-16's up front on 5.5 inch wheels, but we would need to know the offset they used. They don't stick out very far, so I'm guessing an offset in the 4o to 45mm range, but we would need to know exactly . . . . There is very, very little room for error on the front to clear the suspension - Nearly any wheel will fit the rear

I don't know of any car running around on stock 16 x 5.5 wheels, so doing this probably means a set of Work Wheels like they used on the Rinspeed car . . . . and that's going to mean about $2500 for new wheels and tires - A bit rich for my blood

Don

Don, does this mean that the 15in miata wheels (15x6 et40-45 I presume?) you tried earlier don't actually fit on the front? If those fit, that would be one of the best options with all the 15in tire choices available.

btw, base lotus elise wheels are 16x5.5 et31 front and 17x7.5 et38 rear with a 56.6mm centerbore, and usually go for about $400+shipping for a (pre-owned) set, so you could probably run 175/50/R16 front and 195/40/R17 rear if you like. Or you could get two sets of fronts to run 16s all around, but either way, I'd be a little worried about the limited tire choices available in those sizes.

 

[Don]

Don, does this mean that the 15in miata wheels (15x6 et40-45 I presume?) you tried earlier don't actually fit on the front? If those fit, that would be one of the best options with all the 15in tire choices available.

I covered that possibility in an earlier post

So, before I pulled the trigger, I went back to measuring what *should* fit by mounting other 4 x 100 alloys I have laying around. Sad to say, There is no way any 6 inch wide wheel of suitable (or even unsuitable) offset will fit the front end of this car . . . . period!

I came to this conclusion by mounting a 15X6 Miata BBS wheel on the front of my car

Whatever you choose for the front (14's, 15's or 16's) they'll have to be 5 or 5.5 inches wide

Don

 

[Llecentaur]

Interesting post on stock tires.

Tired of trying to find a solution, I finally put the original LRR tires on. Please note this was the first time I drove the car with these.

Simply said I am quite surprised and actually wanted to ask forum members how much they estimate these tires contribute to the fuel efficiency. Besides the improved battery efficiency due to higher temperature I feel that these tires contribute between 5 to 10 % to range.

Besides that, the car feels so much quieter and more stable than with my Blizzard Snow tires.

I am indeed having second thoughts on changing the tires now.

 

[alohart]

Besides the improved battery efficiency due to higher temperature I feel that these tires contribute between 5 to 10 % to range.

First-generation Honda Insight hybrid drivers have been trying to find a replacement for their OEM low-rolling-resistance tires that were designed in the late 1990's. But no tire to date has been found to have a lower rolling resistance which is pretty incredible after all these years. Even the second-best tire appears to decrease fuel efficiency by 5-10%. So your observation is almost certainly underestimating your improved battery efficiency compared with winter tires which tend to have a higher rolling resistance than summer tires.

With the i-MiEV range at the lower end of acceptability for many people when its battery pack is new, and with a loss in range certain as our battery packs age, I do not want to substitute tires with higher rolling resistance than our OEM tires. I'm afraid that finding acceptable substitutes will be difficult, especially in North America where there are a much lower percentage of small, light cars than in much of the rest of the world.

 

[RobertC]

The i-MiEV's Curb Weight and GVWR are 2579lbs and 3329lbs giving you 750lbs for passengers and cargo. You should not exceed your vehicles gross vehicle weight rating. I love the way the i-MiEV handles and I have great fun driving it. 13,500 miles in 10 months and I drive it like its stolen. Floor it, it's a blast.

 

[melloyello]

Sad to say, There is no way any 6 inch wide wheel of suitable (or even unsuitable) offset will fit the front end of this car . . . . period!

I came to this conclusion by mounting a 15X6 Miata BBS wheel on the front of my car

Whatever you choose for the front (14's, 15's or 16's) they'll have to be 5 or 5.5 inches wide

Don

thanks for the clarification and all your work testing wheel fitments on the i-miev

another option are base mini cooper wheels which come in 15x5.5 et45 and a 56.1mm centerbore so it sounds like they'll require machining on the fronts based on your testing. :|

 

[blownb310]

Another option are base mini cooper wheels which come in 15x5.5 et45 and a 56.1mm centerbore so it sounds like they'll require machining on the fronts based on your testing.

Are the base Mini wheels steel or aluminum please?

 

[Don]

another option are base mini cooper wheels which come in 15x5.5 et45 and a 56.1mm centerbore so it sounds like they'll require machining on the fronts based on your testing. :|

Those look very promising! They're plentiful and relatively cheap on eBay and there are 3 or 4 different sets of 15 x 5.5 inch alloy wheels to choose from . . . . they also come in 16 and 17 sizes I believe, but I didn't look at those

Machining the centerbore of 2 of the wheels to fit our front spindles is pretty easy to do and should only cost about $25 per wheel - I've had this done to two sets of RX-7 basketweave BBS wheels to make them fit my FWD Protégé 5. Very little metal needs to be cut and it doesn't weaken the wheel in any way. Also, you could just grind the lip off the front spindles and then any 4 x 100 wheel would fit . . . . but I would recommend modifying the wheel I think

Thanks for the suggestion,

Don

 

[jray3]

Another option are base mini cooper wheels which come in 15x5.5 et45 and a 56.1mm centerbore so it sounds like they'll require machining on the fronts based on your testing.

Are the base Mini wheels steel or aluminum please?

Minis come with lotsa different wheels. Here's a guide. http://libraryofmotoring.info/facts/wheels/

 

[Don]

The i-MiEV's Curb Weight and GVWR are 2579lbs and 3329lbs giving you 750lbs for passengers and cargo. You should not exceed your vehicles gross vehicle weight rating.

You're right, of course - Very good advice

It appears the 3329 max weight rating is limited by the tires, specifically the tiny front tires. The car has an actual weight distribution of 45/55, F/R which means 45% of that 3329 pounds (1498 lbs) is resting on the tiny front tires, which are rated for a max weight load of 783 lbs each, or 1566 pounds - No reserve margin of safety left there at all :shock:

By comparison, the rear tires are carrying 55% of that 3329 lbs which is 1830 pounds, or 915 lbs per tire. The stock 175/60-15 tires are rated for a maximum of 1019 lbs each

I'm not familiar with any other vehicle which cuts so closely to the absolute maximum ratings of it's rubber. More than ever, this convinces me that the suspension and tires were not really designed for this car, but for the 1960 pound I kei car they originally came on - This *really* makes me wonder how the Feds allowed this car to be sold in the USA!

Don

 

[jray3]

I'm not familiar with any other vehicle which cuts so closely to the absolute maximum ratings of it's rubber. More than ever, this convinces me that the suspension and tires were not really designed for this car, but for the 1960 pound I kei car they originally came on - This *really* makes me wonder how the Feds allowed this car to be sold in the USA!
Don

Don, for one in such a sunny climate you sure do rain a lot.
I've been wondering about that, given that all our suspension components seem to be shared with the Kei version. Since our cars are wider and less tippy, I've been itching to screw on some sticky tires and run cones at an SCCA event. Surely only something as dramatic as hitting a curb or pothole would damage the front suspension, and not just increased cornering vectors (when front end sticks in a corner rather than sliding out). :?:

 

[alohart]

Since our cars are wider and less tippy, I've been itching to screw on some sticky tires and run cones at an SCCA event. Surely only something as dramatic as hitting a curb or pothole would damage the front suspension, and not just increased cornering vectors (when front end sticks in a corner rather than sliding out). :?:

The detailed German study of the i-MiEV posted yesterday makes me wonder how well the i-MiEV would perform with sticky tires. The torsional rigidity of the i-MiEV's body seems to be pretty poor, even compared with the VW Polo. The i-MiEV might need a lot of structural bracing to keep its tires planted firmly on the pavement.

 

[Don]

Don, for one in such a sunny climate you sure do rain a lot.

Actually, it rains just as much here as it does there

I was raised in Bellevue and I was stationed at McChord there in Tacoma for 2 or 3 years. The rain you get in 180 days or so (60 to 65 inches?) we get in 15 or 20 days - Not at all unusual for it to rain here for half an hour and get an inch or more of rain :shock:

I'm sure there's a chance that a set of sticky tires *could* overload something else in the suspension when they stick to the corner instead of washing out, but I'm still going to try. I'm 99% convinced (and disappointed) that they didn't change a darned thing from what they put under the little lightweight kei city car

Assuming I end up with a set of the 15 x 5.5 Mini wheels, I'm going to go with a matched set of Yokohama S Drive Ultra High Performance Summer tires, size 185/55-15 on the front and 195/55-15 on the rear. The rear tires are the same exact circumference as the stock 175/60 tire on there now and both of the sizes are 'legal' for 5.5 inch rims. I'm not at all concerned that they're not LRR tires . . . . I'll give up a little range for some GRIP any day . . . . especially in wet weather, which is what summer tires were designed for. I can still run 51 psi in them, so I doubt the hit in range is anymore than 5% or so . . . . well worth it to me. I have sets of the Yoko S Drives now on both my Miata and my Protégé 5, all on the super lightweight BBS basket weave wheels, so I already know I'll LOVE the tires

Gotta be more FUN to drive! - It might do surprisingly well on your local auto X course :idea:

Don

 

[fjpod]

I don't get it. Why does everybody want to change their tires and wheels for something "better"?

 

[aarond12]

Depends on your definition of "better". Many people are concerned about the significant understeer of the i-MiEV because of its smaller tires. (Solution: Add throttle! :lol Some prefer the appearance of wider/larger tires and wheels.

 

[alohart]

Many people are concerned about the significant understeer of the i-MiEV because of its smaller tires. (Solution: Add throttle! :lol

Not a great solution when entering a downhill turn a little too hot

I would prefer to have the same wheels and tires front and back with the tires being low-rolling-resistance tires in an easy-to-find size of the same diameter as the OEM rear tires to avoid speedometer error. For 17 years, I drove a mid-engine 2,100-pound Porsche with about the same front/rear weight distribution as the i-MiEV. Porsche equipped it with the same 5.5 x 15 wheels and 165/80R15 tires front and back. That was by far the best-handling car I've owned with no oversteer or understeer problems. The i-MiEV is heavier, so installing a set of LRR 165R15 tires on the OEM front wheels might be interesting although the 4" wheel width would be a bit narrow. That would be the least expensive option and should improve or eliminate the understeer.

I agree with Don that Mitsubishi appears to have done little or nothing to update the suspension, wheels, and tires to deal with the i-MiEV's significant weigh increase over its ICE kei car sibling. So I look forward to the results of experimentation with different wheel/tire combinations so that when the time comes to replace my tires, I'll have some options that would work.

 

[Llecentaur]

Definitely, putting 165 by 15 tires on the OEM wheel would be the cheapest. But I was told that 145 was the widest a 4" wheel can take. Maybe the max width also depends of the tire construction. Would be great to have a confirmation.

Also someone on the forum was referring to suspensions. Should we not rather look at shock absorbers to improve handling and try and adapt the front drive train to the heavier car?