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You also have to consider the lower moment of inertia from 17” to 16” wheels.
 

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You also have to consider the lower moment of inertia from 17” to 16” wheels.
If in response to me, the weight differences were for the respective diameter wheel.
 

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Been a while since I've done any physics like this, but if it was only an overall weight difference including wheels/tires, wouldn't that affect the city fuel economy numbers more than the highway numbers? I don't know how EPA calculates, but if at a steady speed in a straight line, I'd think the wheel weight and overall weight wouldn't be major factors like they would be in city stop and go traffic. Tire width, rolling resistance and aerodynamics and other factors would affect highway mileage differences, of course.
 

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Been a while since I've done any physics like this, but if it was only an overall weight difference including wheels/tires, wouldn't that affect the city fuel economy numbers more than the highway numbers? I don't know how EPA calculates, but if at a steady speed in a straight line, I'd think the wheel weight and overall weight wouldn't be major factors like they would be in city stop and go traffic. Tire width, rolling resistance and aerodynamics and other factors would affect highway mileage differences, of course.
Just to share as an FYI - the EPA tests aren't quite at steady state speeds. Their testing protocol specifies a top speed, max acceleration rate, temperature, and reports the average tested speed.
 

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Just to share as an FYI - the EPA tests aren't quite at steady state speeds. Their testing protocol specifies a top speed, max acceleration rate, temperature, and reports the average tested speed.
I would hope the highway profile is a lot more consistent than the city one. I'll see what I can learn tomorrow, but it sure seems like something else would have to vary besides a few percent in weight for there to be the same 4 mpg difference both city and highway.

Edit, here it is: LA4 vs. HWFET https://www.epa.gov/vehicle-and-fuel-emissions-testing/dynamometer-drive-schedules
 

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So has anyone got new rims and got better real world MPG?

If so what rims? (For touring model)

@Jason posted about getting lighter wheels (Maxxim Winner) and smaller tires for the Touring earlier in this thread (post #14), with better fuel efficiency as primary objective. The new wheel weight was ~52 lb lighter (plus another 4 lb weight savings from smaller tires). Hoping he can update and share here what the net MPG gains have been after the change...

@ATMANBA separately posted about getting lighter wheels (Sparco Assetta Garas) for OEM tires on the EX in separate thread, where we're hoping to hear what the fuel efficiency gains are for the 22 lb weight reduction.
 

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Been a while since I've done any physics like this, but if it was only an overall weight difference including wheels/tires, wouldn't that affect the city fuel economy numbers more than the highway numbers? I don't know how EPA calculates, but if at a steady speed in a straight line, I'd think the wheel weight and overall weight wouldn't be major factors like they would be in city stop and go traffic. Tire width, rolling resistance and aerodynamics and other factors would affect highway mileage differences, of course.
Short answer yes, lighter wheels/tires would primarily affect fuel mileage during acceleration. Heavier wheels/tires are slightly better for coasting (higher inertia), but there is a limit to that benefit.

Lighter always benefits acceleration, heavier only benefits coasting (and to a smaller degree regenerative braking).
 

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Searching the OEM part number the only site I could find with a weight says it is 29 lbs. so yeah, there is that.

I am bored enough to pull off a wheel and weight it... not going to remove the rubber though. I could just message Honda too, but their response is often humorous... maybe I should anyway.
 

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I’m thinking about buying 1 wheel from my local Honda dealer ,weighing it, and then returning it. Nothing out of pocket vs removing wheel/tire and mounting again.
 

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I’m thinking about buying 1 wheel from my local Honda dealer ,weighing it, and then returning it. Nothing out of pocket vs removing wheel/tire and mounting again.
Why not just bring your scale to the dealer and ask to weigh one? It's a lot of paperwork to just buy a wheel from a dealer.
 

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Why not just bring your scale to the dealer and ask to weigh one? It's a lot of paperwork to just buy a wheel from a dealer.
That’s probably a better idea. The only problem is the dealer most likely won’t have it, but I can call around to a few dealers to see if they have the wheel in stock without having to order it.

This wheel will most likely be special order item.
 

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I messaged some people selling OEM rims on eBay. My responses for weight were 99% "I do not know." I did get one reply on the 17" Touring that it was "25 lbs when packaged."
 

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There’s probably a way to get the weight of the wheel only by getting the weight of your tire and how many psi that tire is inflated to and checking online how much air at that PSI for that exact wheel and tire spec weighs...I’m sure there is something online with air weight for tire and wheel sizes.

Then deducting the tire weight and air weight from the overall weight of tire and wheel.

The only problem is it wouldn’t be exact because your tire tread is less after being driven and the tire would be a little lighter then spec.
 

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Okay, factory wheel. 20k miles. 35ish PSI. We have...

6042


for the 16" that comes on the EX. I remember to do stuff eventually.

In theory... the rubber itself is 21 pounds. So the rim is 23ish pounds give or take a bit for worn tread and acts of nature.
 
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