Wheels, Rims, and Tires

[JoeS]

The one controlled test I did used the GPS mileage and not the car's odometer.
Today I paid attention to the GPS vs. indicated speed and at 30mph on the GPS the car was showing 29mph. Now have over 3000miles on the Yokohamas.
Just came back from a hypermiling run up and over the hill to the ocean. Will download the consumption from ChargePoint and just now plugged in the car and intend to fully recharge and hope to post the performance tomorrow. For distances I only use the GPS, so it's tire-diameter independent.

 

[JoeS]

OK, with over 3000 miles on my new Yokohama tires, here's the trip yesterday afternoon going to Capitola (on the coast) from home (600' net altitude drop, but going over 1800ft summit along the way) and last night coming back, just a little longer than this trip (see graph). One of the differences is that I stayed on the freeway instead of taking a slightly shorter and slower-speed road for about five miles, but also ended up driving in town in Capitola to avoid the freeway traffic jam. Tire pressure 51psi. Going, the temperature was around 70degF, coming back was around 60degF. No use of either aircon or heater or seat heater, but headlights on coming back. One person in the car, with about 50# of stuff in back. Traffic was heavy going to the coast, but very light coming back. Kept the freeway speeds in the 50's, coasting wherever possible.

Here's the data (all distances are off the GPS, with RR off the instrument panel):

Left home fully charged (16 bars), mileage 000, RR=55 (ugh!)
Arrived Capitola with 7 bars, odo = 40.7miles, RR=36 (good)
Charged in Capitola using ChargePoint (208vac?) 8.917kWh
After charging, RR=89 (WOW!)

Drove a few miles around Capitola after charging.

Left Capitola, 16 bars, odo = 43.6miles, RR=86
Arrived home, 3 bars, odo = 85.4 miles, RR=11
Charged overnight 120vac 12A, 11.776kWh (T.E.D.), after charge RR=58(UGH!)

Consumption going: 40.7/8.917 = 4.564mi/kWh (219Wh/mi)
Consumption coming back after Capitola charge: (85.4-40.7)/11.776 = 3.796mi/kWh

Trip overall: 85.4/(8.917+11.776) = 4.127 mi/kWh (242Wh/mi)

Comments:
1. Going I stayed with the heavy commute traffic and thus did not hypermile much and yet the consumption was pretty good, attributable to the 600' net altitude drop.
2. Coming back I was disappointed at not doing better (despite the altitude climb), as traffic was very light, but perhaps I didn't hypermile as carefully as I could/should have as it was late...
3. REALLY DISAPPOINTING was my RR = 58 this morning after a full recharge (I expected it to be around 75); but I also recognize that the last 15 miles were freeway driving followed by a 2-mile 300' climb
4. I just realized that my previous trip is not a good baseline because it was only a recorded half-trip.
5. I recorded the outgoing trip on Canion, but haven't looked at it yet.
6. Apologies to our international friends for not converting to metric (I'm in a bit of a hurry).

Back On-Topic: ever since I installed the new tires I haven't seen a fully-charged RR number over 71, so it was encouraging to have that RR=89 pop up - yes, those last 15 miles into Capitola before recharging are indeed all downhill down to the ocean.

So, are Yokohama AVID ENVigors worse than Dunlop Enasaves from a rolling-resistance perspective? Subjectively I think so (and thus would not buy the Yokohamas again), but there are too many variables and we all know that the driver is the biggest variable in a vehicle's range.

 

[PV1]

Comments:
1. Going I stayed with the heavy commute traffic and thus did not hypermile much and yet the consumption was pretty good, attributable to the 600' net altitude drop.

How close were you following the vehicle in front of you? 1-3 carlengths or way back? I drove the highway home one day in heavy traffic (talking 1-2 car lengths behind the person in front of me at about 55 mph), both lanes solid cars. I used just a tad more energy than on the main road.

No need to hypermile if you're not pushing air.

 

[misterbleepy]

Do you have really abrasive roads over there?
Those tyres are almost bald (and in this country would get you into serious trouble with the law)!

Here are photos (taken on 30 December 2013) of the four tires which had been run at 60psi for 22,000 miles before I rotated them:

 

[jray3]

Do you have really abrasive roads over there?
Those tyres are almost bald (and in this country would get you into serious trouble with the law)!

I don't know about Joe's roads, but he does get 300+ days without rain per year! My western Washingtonian tires seem to wear more slowly because they are almost always lubricated with rainwater (sleet and hail yesterday) and stay cold and hard rather than hot and soft...

HowEVer, when I moved to the Pacific Northwest from the Southeastern US, I was struck by how rough the roads are. They use a much coarser crushed aggregate than the smooth southern asphalt that's often no more than small sandy round pebbles plus tar, and have a high percentage of concrete roads, which get cracked up by the heavy truck traffic. (105,500 lb weight limit rather than 80,000 lb) We are also stung by studded tires rutting and roughening up the roads, something Joe probably doesn't need to worry about.

 

[misterbleepy]

I just looked up average rainfall for San Jose - about 400mm per year - we've had close to that already where I live in the UK (just over 390mm) - and I live in about the only part of the UK where palm trees are a common sight outdoors.
The roads have a variety of surfaces, and locally there's always windblown sand on them. Some of the lesser used lanes I use are so narrow that grass grows through the tarmac down the centre of the road - that keeps your speed down, especially around harvest time.
I'd like to get good mileage out of my tyres, but we have to replace them if any part of the tread is shallower than 1.6mm deep. I'm hoping with the car being RWD the wear will be more even than on a FWD car.

 

[PV1]

Does anybody have any experience with the Continental tires for the i-MiEV? I'm about ready for a new set (and a front-end alignment).

 

[jray3]

Does anybody have any experience with the Continental tires? quote]
Not on my i, but Continental Eco-Contact have been popular as summer street tires among NEDRA drag racers, and they come in our size range. They're LRR and original equipment for the 2004-2006 Smart car. I like the idea of that outer solid tread band for improved cornering/reduced wear, though the compound they use is not recommended for colder temperatures.

Tire Rack has 145/65R15 on sale for $75 and the closest they've got for our rears is 175/55R15 for $83

http://www.tirerack.com/tires/tires.jsp?tireMake=Continental&tireModel=ContiEcoContact+EP

Otmar has been using EcoContacts on the California Poppy (high performance electric Porsche 914) for many years....
http://www.evalbum.com/293

 

[PV1]

$200 cheaper than Dunlops. I might try them out. My usage of the car won't be impacted for the most part by any loss of range these may cause. I'd like to switch while I still have some tread left so I have a spare should one blow out.

 

[carnut1100]

My girlfriend blew out a front tyre in a pothole so we put the continental 155s on both front wheels as it was the same price as one Enersave....
Better handling, less twitchy on bumpy roads and in crosswinds, no range loss that we have noticed....
There must be some loss, but not that we have noticed.

When the tyres on mine wear or i will be going with continental also.

 

[Don]

My girlfriend blew out a front tyre in a pothole so we put the continental 155s on both front wheels as it was the same price as one Enersave....
Better handling, less twitchy on bumpy roads and in crosswinds, no range loss that we have noticed....
There must be some loss, but not that we have noticed.

Same experience here. I blew one front tire when I hit a chunk of asphalt which had fallen out of a dump truck and I replaced both front tires with Continental EcoContact EP in 145/65R15 . . . . the same as the original size. Here, virtually no tire dealer wiil install a tire of a different size from what's shown on the door sticker. These tires were the only thing my local guy could get me on an hours notice. They are made in France and so far I'm very happy with them. Think we have about 3,000 miles on them at this point. When we need new rear tires, I'll get another pair of them

Don

 

[JoeS]

... I replaced both front tires with Continental EcoContact EP in 145/65R15 . . . . the same as the original size. Here, virtually no tire dealer wiil install a tire of a different size from what's shown on the door sticker. These tires were the only thing my local guy could get me on an hours notice. They are made in France and so far I'm very happy with them. Think we have about 3,000 miles on them at this point. When we need new rear tires, I'll get another pair of them.

Don, I take it you haven't noticed any change in your range? We're still bemused by our range loss after installing the Yokohamas, but have been sharpening our hypermiling skills to compensate when needed.

 

[Barbagris]

Continental EcoContact EP no longer manufactured; today they have EcoContact 3

http://www.continental-tyres.co.uk/www/tyres_uk_en/themes/car-tyres/standard-car-tyres/contiecocontact/contiecocontact-ep.html

But seems now don't make the size 145/65-15...

 

[Don]

... I replaced both front tires with Continental EcoContact EP in 145/65R15 . . . . the same as the original size. Here, virtually no tire dealer wiil install a tire of a different size from what's shown on the door sticker. These tires were the only thing my local guy could get me on an hours notice. They are made in France and so far I'm very happy with them. Think we have about 3,000 miles on them at this point. When we need new rear tires, I'll get another pair of them.

Don, I take it you haven't noticed any change in your range?

Nope - We hit our two year point today and a full recharge gave an RR of 87 - The best we've ever seen is 88. 8 Bars usually shows 40 miles remaining, +/- one or two just as it always has. Can't see any difference between the Continentals and the Dunlops, mileage wise

Don

 

[FiddlerJohn]

... and a front-end alignment.

... Though there is no front camber adjustment mechanism- would have to go custom.) Bottom line- if you have an annoying rattle in the front end- check the swaybar studs! The two nuts mounting each strut top to the fender ...

The is no CAMBER, CASTER or KINGPIN alignment mechanism. Only TOE-IN can be easily aligned. If your front tires are wearing on the inside, your tires are pointing outward. The MiEV front wheels should point straight ahead for zero TOE-IN.

If your steering is not centered do the TOE-IN adjustment one side only. If the steering points to the LEFT, then shorten the tie-rod on the RIGHT. Try about one full turn.

If your front tires are wearing on the inside and the steering is straight (shorten) CORRECTION: LENGTHEN each TIE-ROD (unscrewed) about half a turn.

1. Loosen the locking nut with tie-rod bellows clip removed,
2. Perform the adjustment by turning the TIE-RODS.
note The toe moves to the outside by turning the tie-rod: left to the forward direction, and right to the reverse direction.
2. Install the tie-rod clip, and tighten the lock nut to the specified torque. Tightening torque: 34 ± 5 N·m
3 .Check the toe-in standard value of ZERO.
4. After adjustment, check that the steering is straight ahead.

 

[tomrh]

My girlfriend blew out a front tyre in a pothole so we put the continental 155s on both front wheels as it was the same price as one Enersave....
Better handling, less twitchy on bumpy roads and in crosswinds, no range loss that we have noticed....

I ordered 155/60-15 of Pirelli Cinturato P1 since they have less rolling resistance than the continentals mentioned. My experiences are the same, the car is much more stable now. I don't have to adjust the steering everytime someone lets a fart out in the parallell lane...

 

[tomrh]

Btw - did anyone manage to fit 14" rims on the i-MiEV?

We have had some problems during this winter with icy roads, and a number of times I had to leave our i-MiEV further down the road at our neighbour's place and walk home. Spiked winter tyres would help. I have not found anything fitting on the 15" rims, but on 14" rims there are available tyres. A guy on the norwegian EV forum did try but it wouldn't fit because of the brake calipers. But the rim was only about a few millimeters too small, so a differently shaped rim might fit?

 

[Don]

I have an extra set of Miata 14 inch wheels/tires and I did try fitting them some time ago. There is no problem at all putting most any width 14 inch rim on the drive axle in the rear, so you could definitely use a set of 14 inch studded tires there if you like - A 195/60R14 tire would give you about the same overall circumference as the OEM tire

The front is another matter. You'd need a 5 inch wide rim (or narrower) to clear the front struts and my Miata wheels were too wide. I don't recall if there was a caliper clearance issue or not, but I don't think so. I do have a compact spare from a Miata with a much narrower rim which *might* fit . . . . but could you find a studded snow tire to fit that narrow rim?

Don

 

[tomrh]

Nokian Hakkapeliitta 7 w/spikes comes in 155/70-14 (only 4 mm wider diameter than the original 145/65-15). For the rear tyres I could choose 165/65-14 or 175/65-14, there are a lot of spiked tyres to choose from - especially in the 175-width.
I found a suitable 4,5"/14" Dezent L rim: http://www.dezent-wheels.com/438_DE.htm?webdid=382 (cf. Daten & Grösen), it comes w/offsets ET39 and ET45. Do you think it would fit on all wheels?

 

[Don]

I *think* they would fit the front - They'd be OK on the back for sure

Interesting that you have a better selection of studded 14 inch tires than 15's

Don