Having also replaced my stock wheels and tires, I think a few things are potential FE hits: tire width, tire composition (LRR or not), wheel aeordynamics, and wheel weight. My tires are only 195's opposed to the 185's I started with, so I don't think width was a factor. I replaced LRR with LRR. I even dropped 2.3 lbs per wheel in weight. Net result - so far no change that I can tell (better or worse). So that's good news. However given everything else was fairly even, and I even dropped weight, I would have expected a small increase in FE. So I'm wondering if the drag of the spoked wheels really makes more of a difference than I originally thought - especialy at highway speeds.

 

does anybody know the weight of the stock wheel and tire combo? i would want to know to see how much more or less my current set up is.

 

There were some earlier posts about that.
I remember that being a highly guarded Honda secret.
I also thought someone actually WEIGHED one ( what a novel thought - I'm sure Honda NEVER saw that coming!).

 

I was amazed at how little Honda would tell me. When I called customer service, there were either unable or unwilling to part with the data. Tire weight can be found on TireRack or on the manufacturer's site. In the case of the Dunlops, I actually had to contact the company directly (as the SP20's are not widely advertised to the public). I only found the true weight of the OEM wheel after removing it and putting it on a scale. Here was the data from my replacement - however it's from an HCH I.

Original setup was (31.8 lbs)
14" OEM Wheel (14.2 lbs, weighed on doctor scale)
185/70R14 Dunlop SP FE (17.6 lbs, from Dunlop)

New setup is (29.1 lbs)
15" Kosei K-1 TS (10.8 lbs, weighed on scale and from Kosei)
195/60R15 Continental ContiTouringContact CV95 (18.3 lbs, from Continental)

 

I think this easily could make a big difference as the whole wheel is completely open, the spokes themselves create more frontal area than a flat rim, and wider wheels/tires would tend to stick out slightly further into the stream of air around the car.

For the first thousand miles, or even longer, expect the tires to break in. On a known stretch near my house, I coast down a hill, then use the momentum to roll up and over a smaller hill. my speed at the top of the second hill on my original tires was about 20mph. The first week on my new tires, I barely made it, and would actually have to get on the gas to maintain speed. Now though, I can coast the whole way at about the same speed as before (I never measured it very precisely). My actual mileage though hasn't improved much since then as I've tended to offset the improvements in rolling resistance by driving faster on the freeway

 

Well, I just read about the break in period about the tires. So, hopefully things will get better after 500 miles on the new tires. But, this morning on my commute to work the loss doesn't seem to be too bad. about 2-3 mpg. but, traffic was really light this morning. i will post results as temps warm back up and driving conditions are about the same as when I had the stock set up.

 

Any updates?

I am looking at Motegi Racing TrakLites (17X7 weigh 14 pounds) and I am curious what you have noticed with your set up.

 

HCHII has a stock wheel/tire combo weight of about 34 lbs.

 

Well, the new set up of wheels and tires have eaten my fe. I suspect it is the tires since they are not non-rolling resistance tires. But, the loss was about 5 mpg. But, it is worth it to me for the handling and performance.

 

According to www.tirerack.com the factory tires weigh 18 pounds alone. This would mean the wheels weigh 16 pounds.