StEVen
Posts: 18
Joined: Wed Oct 17, 2018 2:21 pm

195/55r15 on all 4 corners for over 7000 miles. UPDATE!

Mon Jan 14, 2019 10:59 pm

Hi everyone. A bit ago I posted a question here if anyone had any numbers on running a 195 up front. Well I went ahead with my project and here are the results.
I picked the General Tire RT43 because it is very well rated and there is a 185 profile so if I didn't like the result I could put the stock size back on the front. The tire also has a tread wear rating of 600 A A so a good bit higher than even the stock "LLR or efficient" tires. Ultimate goal was 4 same wheels/tires for a standard rotation. Purchased two extra fronts ;)
My miles per kilowatt hour before the switch was 5.2 over the course of 500 miles. I did this twice in a row just before I got the new tires and got the same result. After the switch to the larger tire up front & all around I am now getting 5.3 mi/kwh. Same thing run twice now. So about the same thing. I think the rolling efficiency of the new tire is offsetting any loss due to the larger tire. I do notice that the green trending dots above the center GOM estimator fluctuate up and down quicker but my overall miles has stayed the same and fluctuates between 77 and 85 miles depending on who drove it last.
Lastly besides the obviously more comfortable ride from having a larger tire up front I notice that my headlights are at exactly the right height now too Lol. The car handles better than ever and It will be a joy to rotate the tires like a normal car.
GM really could have put the same size tire on all four corners on this thing.
Last edited by StEVen on Tue Sep 17, 2019 7:23 pm, edited 4 times in total.
2nd owner
'15 2LT w/ DCFC
21k miles
Stock front wheels w/ 195's on all 4 corners.
Sold for my next EV which is yet to be decided.

NORTON
Posts: 1337
Joined: Fri May 01, 2015 5:52 am
Location: KC,MO

Re: 195/55r15 up front for over 1k miles. numbers

Wed Jan 16, 2019 4:56 am

Good report !

Only this: "Ultimate goal is 4 same wheels/tires for a standard rotation. Purchased two extra fronts"

Are you saying you bought an extra set of front wheels?
You know the front and back wheels are different and you can't rotate the stock wheels front and back.
You know lots of cars don't allow any tire rotation at all because of direction tires and different wheel sizes front/rear.
Used '14 2LT w/ DCFC. +85k miles.
Mostly free charging! Only one LONG visit to the shop....
GM needs Modern Troubleshooting tools for Modern EV's.
3 step Trouble Tree, 1st try car died again, 2nd try / cost $800. 3rd try fixed the problem.

StEVen
Posts: 18
Joined: Wed Oct 17, 2018 2:21 pm

Re: 195/55r15 up front for over 1k miles. numbers

Thu Jan 17, 2019 9:53 pm

Hey. Yes. I am saying that I purchased two used front wheels. The rear wheel is the wheel that can't be mounted up front. The front wheel can be mounted on the rear with no trouble at all. So now YES, I have the same exact tire and wheel combo on all 4 corners that can be rotated like so many cars on the road today. I did not purchase tires that can only be run in one direction. The rear to front wheel offset is within 5mm per side and the width is now 6" wide vs. 6 1/2". You literally cannot tell by looking unless you knew to begin with. Also not rotating all 4 tires in a standard rotation cuts your tire warranty in half. This way I keep my 60k mile warranty. And on an electric car with 300+ pound feet of torque I will be using this warranty. Its absolutely wonderful, the car feels balanced and totally normal in every respect and I love the convenience of pulling in for a STD rotation and not having to peek my head out to make sure things are done right. Or do it myself because I don't have to peel and remount the tires.
2nd owner
'15 2LT w/ DCFC
21k miles
Stock front wheels w/ 195's on all 4 corners.
Sold for my next EV which is yet to be decided.

NORTON
Posts: 1337
Joined: Fri May 01, 2015 5:52 am
Location: KC,MO

Re: 195/55r15 up front for over 1k miles. numbers

Fri Jan 18, 2019 4:40 am

"The front wheel can be mounted on the rear with no trouble at all. So now YES, I have the same exact tire and wheel combo on all 4 corners that can be rotated like so many cars on the road today. I did not purchase tires that can only be run in one direction. The rear to front wheel offset is within 5mm per side and the width is now 6" wide vs. 6 1/2". You literally cannot tell by looking unless you knew to begin with. Also not rotating all 4 tires in a standard rotation cuts your tire warranty in half. This way I keep my 60k mile warranty."

Good stuff to know!!!
Thanks !
Used '14 2LT w/ DCFC. +85k miles.
Mostly free charging! Only one LONG visit to the shop....
GM needs Modern Troubleshooting tools for Modern EV's.
3 step Trouble Tree, 1st try car died again, 2nd try / cost $800. 3rd try fixed the problem.

dennali

Re: 195/55r15 up front for over 1k miles. numbers

Sat Jan 19, 2019 2:30 pm

I'm looking a installing 16" tires and aluminum wheels. Has anyone done this? I see in the other post someone matched the size on all four wheels with no ill effect.

NORTON
Posts: 1337
Joined: Fri May 01, 2015 5:52 am
Location: KC,MO

Re: 195/55r15 up front for over 1k miles. numbers

Sat Jan 19, 2019 7:00 pm

dennali wrote:
Sat Jan 19, 2019 2:30 pm
I'm looking a installing 16" tires and aluminum wheels. Has anyone done this? I see in the other post someone matched the size on all four wheels with no ill effect.
Keep searching. There are some great pics and specs in a thread here.

Of cause fatter tires are not going to be as good as LRR tires for range.. But great on grip !!

Go forth and find that Cooper S 8-)
Silently !!! :mrgreen:
Used '14 2LT w/ DCFC. +85k miles.
Mostly free charging! Only one LONG visit to the shop....
GM needs Modern Troubleshooting tools for Modern EV's.
3 step Trouble Tree, 1st try car died again, 2nd try / cost $800. 3rd try fixed the problem.

StEVen
Posts: 18
Joined: Wed Oct 17, 2018 2:21 pm

Re: 195/55r15 up front for over 1k miles. numbers

Tue Sep 17, 2019 7:22 pm

An update on my set up. I have 4 front OE wheels on all four corners of my Spark EV (I purchased two additional used front wheels and mounted them on the rear). I did this because the front wheel fits on all 4 corners of the car without issue and allowed total clearance of the wheel and tire. I mounted the General tire RT-43 195/55r15 which is the stock rear tire size on these 4 wheels and have been rotating them several times now. I am getting outstanding results with anywhere from 75 to 85 miles on this little guy with each charge depending on how I drove for the week. My commute is ideal with back roads and city stop and go which is what this car was made for. I find the tire to preform very well in both wet and dry conditions and have no regrets, no rubbing or any issues at all. I know its popular to try to put expensive performance wheels and tires on this little hot rod but it really is no more than a 4 seat golf cart with 10 airbags so its not really practical in my book.
2nd owner
'15 2LT w/ DCFC
21k miles
Stock front wheels w/ 195's on all 4 corners.
Sold for my next EV which is yet to be decided.

an7mal
Posts: 2
Joined: Thu Sep 03, 2020 4:32 am

Re: 195/55r15 on all 4 corners for over 7000 miles. UPDATE!

Thu Sep 03, 2020 5:57 am

I think 195/55R15 on the front are a good idea.

https://photos.google.com/photo/AF1QipM ... Z6E1IzVFEV
I Installed 195/60R15 on all four corners per above pic (hopefully my pictures work here). I did this because the stock tire size seemed like roller skates on the bumps I encouter on my daily commute and I wasn't real happy with traction of the low rolling resistance tires. I found a good deal on Cooper Evolution Tour TR tires that were rated M+S and high mileage as my Spark had cord showing on the 2nd set of stock fron t tires within 39k miles.

I wanted 195's because the 185's on the front allow the rims to hit before the sidewalls on curbs - the 195's help considerably with curbing.

The larger 60 series tires are only ~10mm (3/8") bigger radius and do rub slightly at extreme turning angles. The speedo now reads ~3% low. They ride considerably 'softer' over the bumps and have a lot better wet weather traction. Efficiency/range seems to be down a few percent.

If I had to do it over again, I'd probably try to find a high mile, high traction tire in the 195/55R15. There were more options in the 60 series, such as the Pirelli P4 and Cooper tires. I've also considered getting smaller wheels (Honda Fit, Mini Cooper, Miata all come with 14" rims with 4x100 bolt pattern) and trying a taller profile tire, such as 185/65R14, which opens up options. On the smaller, narrower rims curbing the rim with a skinnier tire is less of an issue but tire footprint wouid be reduced.

Clearance of the stock front wheels with 195/60R15:
https://photos.google.com/photo/AF1QipM ... _AwrZuVJXP

Brakes on front/rear appear to have almost no wear with 40k miles:
https://photos.google.com/photo/AF1QipN ... FFqQWD1guf

MINITSLA
Posts: 2
Joined: Sun Feb 16, 2020 1:46 am

Re: 195/55r15 on all 4 corners for over 7000 miles. UPDATE!

Sat Sep 05, 2020 6:01 am

an7mal,
And idea why I can't view any of your Google pics when clicking the links? All that comes up is an error page stating "404. That's an error." and "The requested URL was not found on this server."

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