this also references your comments in the untruths thread, but, i dont think its fair to compare the rolling resistance of pneumatics vs urethane, due to the general size difference. im currently running 5 inch pnuemies; the only comparable urethane i know of are the rare tb130’s, and those are much wider. with actual similar dimensions, im not sure how range or rolling resistance would compare.
Imagining what would happen if you just sent each wheel rolling down the road on its own isn’t relevant since those wheels have very different amounts of inertia, and the dominant source of inertia and load when they’re being used is the rider, not the wheel. Rolling resistance coefficient is determined by, in broad strokes, diameter plus stiffness plus rebound. (Lots of asterisks there tho). I’ve always been under the impression that high rebound urethane can have a lower coefficient then a good pneumatic bike tire, but maybe I’m wrong.
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I mean, they must be compared if we run both on our boards
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Hmmm okay see where you’re coming from. It just always seems to me that with pnuemmies at our size and less than ideal pressure
Rolling inertia does make a big difference too, it’s part of why the heavy as balls eovan RF wheels have nearly as bad consumption as pneumatics
oh for sure, but without testing similar dimension wheels, i dont think its fair to make generalizations like “pneumies kill range” or otherwise directly comparing pneumatic wheels to urethane. they are built very differently. there obviously will be the actual use comparison. but i dont think its fair to compare, say, our standard 6 inch+ pneumies to our generally 100mm or less, much wider, urethane wheels, and generalize about urethane vs pneumatic.
regardless, airless are the real range killers.
Sure about that? An object in motion will stay in motion, and all that jazz. When you are traveling at a constant speed, the angular inertia of the wheel has literally zero effect. When you are accelerating and braking, it has an effect that is a couple orders of magnitude smaller than the inertia of your body
But they do, that’s the thing. Show me any single person in this entire forum that has lower wh/mi consumption on pneumatics (any size) compared to urethane
It’s not fair, but also, what huge urethane wheels do you see that could compare to other large pneumatic wheels?
In our application, urethane is more efficient than pneumatics.
Rubber airless wheels can be pretty bad too. In my experience, they split the difference between urethane and pneumatic.
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No I am not sure, however, I do not know what testing would be able to get the correct answer
I would be interested to know though. It has been a general speculation in the longboarding community that heavier wheels have worse range
No one knows for sure why though
my flash airless are still my favorite wheels ride feel wise, but they literally cut range by 60% compared to 100mm urethane. these 5 inch hoyt tires are a close second, but that wide contact patch on the flash is something else. i dont know how switching to large urethane on this board would affect range, it would probably add some, but im not sure. but then; what would 3 or 4 inch pneumies be like, compared to large urethane? i dont know. the fact that softer wheels have steadily better rolling resistance on that chart makes me question it even more.
It has been demonstrated pretty conclusively via competition results that larger wheels are faster in rollerblading, but when blading wheels get bigger the urethane band doesn’t get thicker. Maybe that’s the difference
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Yeah, they are like scooter wheels, big wheel, thin urethane
However, on the eovan RF, they’re a giant hunk of metal, with thin rubber
Depends on riding surface. Harder Wheels have little resistance on perfect surfaces, but the optimum hardness for a rough surface will be softer, because it’s easier to absorb the bumps than to bounce over them
Here’s some numbers
The range estimates are with a high efficiency rating but I used the same settings for each of them, so they should be scalable
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i get around 19wh/mi on these 5 inch pneumies, pretty sure. personally, love them. ive charged this board one time since it arrived. i wouldnt call that particularly worse than urethane, honestly, but i still feel like that has more to do with wheel size than material. there is definitely a balance to be found.
Interesting, yeah that sounds like a pretty good number
i also have absolutely no free roll on this drive train, i run high negative ramping time to simulate it. these wheels on a belt or DD setup, you could coast forever, which would lead to FAR greater range if you were riding with that in mind.
Whoa tb110s weigh more than rockstar 2s with tire. I always forget how huge those things are.
Isn’t that wild haha
Also, how heavy 9 inch tires are
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urethane is HEAVY. i forget the exact number, but when i questioned urethane car wheels, it was like, 200lb a wheel or something.
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