(ForkenSwift sporting the winning tire: Bridgestone Potenza RE92's, OEM low-rolling-resistance tire of the 1st generation Honda Insight.)
So, on the weekend as you may have seen already, I did some rolling testing of the six (6) different sets of tires that are currently in the Suzukiclone fleet. (Seven sets,
if you count the spare tire donuts, which I also tested.)
I wanted to find out which tires had the best rolling resistance performance (and which ones had the worst).
This info probably may not be particularly useful to anyone else unless you have the same tires. (Which is unlikely, with the exception of the Bridgestone Potenza RE92's, which are still available. And maybe the Goodyear donuts.
)
All the wheel/tire sets were mounted on the same car (ForkenSwift), which was rolled down a gentle hill onto a flat run-out.
Long story short, here's what I learned:
Order of testing - it was sort of an "A-B-C-D-E-F-G-H-A" test...
The how
- All testing was done by mounting the wheels/tires on the ForkenSwift
- I drove each car the same distance to an empty parking lot with a small downhill entrance/exit opening on a level run-out area
- Start: car was stopped with the hand brake at a marked position on the hill, transmission placed in neutral and the brake released
- Finish: after coasting to a stop (max speed < 10 km/h / 6 mph) each run's "end" position was marked on the road with chalk.
- 3 - 5 runs were done for each set of tires
- drove back to the shack, swapped the wheels/tires
- the hydraulic brakes were not used at all during the testing, to avoid as much as possible having the front brake pads dragging on the brake rotors after use
Conditions:
24 C / 75 F - clear & dry
wind WSW 12 km/h (~7 mph)
Here's a pic of the test area, with an accurate representation of the RE92's average finish position compared to the average finish for the donuts (@ 70 psi):
You can see it wasn't that steep a hill. Maybe a 2 foot elevation change. (From:
Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com - View Poll Results )