Belt resistance

Hey everyone, I was wondering if a tighter belt will result in more range? Another builder told me that a tighter belt will result in more power transfer and less energy lost, resulting in more efficiency and range, but I also read somewhere that a looser belt will have less resistance, hence more range. Which is true?

On a side note, I have a pair of old belts that are pretty stretched and makes a squeaking sound whenever the wheel is in motion. The teeth looks pretty solid with not much wear, and the whole belt doesn’t look like its going to fail anytime soon. Should i replace it?

A loose belt will put less strain on the motor. Less strain means less heat, less heat means less losses which means better efficiency. I do my belts as loose as possible without letting the belts slip.

I’m not sure how a tighter belt provides more torque transfer.

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Tight belt creates more resistance in the whole assembly, especially in the bearings. A loose belt will have less resistance as your not restricting the “play” or tolerances of the bearings.

Also everything @Jinra said above ^^^^ resistance = friction = heat.

Loose belts of course are prone to skipping on the smaller pulley. Which is why some like myself run idlers.

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So that means I won’t lose much torque and power from a loose belt?

Wider belts will increase torque transfer. So yes technically a wider belt will give you a couple extra feet of range.

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It’s all about balance, a properly tensioned belt will give you the best range and the best torque transfer. Running your belt super tight will actually reduce torque transfer and range

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Ah, thanks for the clarification

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Regarding a wider belt. Yes there will be better torque transfer.

Wider belts offer more material which takes more force to stretch.

When your under power, the belt stretches on one side and compresses in the other. So the belt is stretching for x time over x distance with x force. (Think rubber band) the stretch is exponential not linear.

Basically a smaller belt during the time it is stretching will stretch more then a wider belt with more material that would require more force to stretch the same distance as the narrower belt.

Of course the side of the pulley the belt is stretching or compressing on depends on if your under throttle or braking.

Less stretch = more efficiency/less wasted energy = more power to ground Think of it kind of like drive shaft flex on a car when doing a wheel dyno vs a flywheel(crank) dyno. The tighter the tolerances the less drive train losses.

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Yea so basically… I was spot on :wink:

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and if too tight, the belt easy to break.

too loose, easy to strip off tooth.

normal tension will be good.

What would be a normal tension? I run my belts very loose but they dont slip. But its loose to a point that theres not much tension. Is that still alright?

Edit: What i mean by not much tension is from what i can tell the belt is slightly curved between the gears, not straight. And i can squeeze them quite abit

I just had a few issues too with an over tight belt being noisey and obviously inefficient too… I loosened it off and now it’s much quieter. I’m hoping he range may be extended by a km or two as well.

The tension is different for all of us. It’s really trial and error for each individual.

Best of luck.

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I have installed hundreds of drive kits, my standard for belt tension is. when you spin the wheel by hand, the motor will follow smoothly, like on the video.

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which type of bearings and bolt did you use? I need this so much for my raptor 1

Full Si3N4 ceramic bearings are certainly the best.

http://www.ebay.com.hk/itm/302325927096?ssPageName=STRK:MESELX:IT&_trksid=p3984.m1555.l2649

As loose as possible without slippage is what I do

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ceramics as an idler seems overkill, no ? (sarcasm)

Of cause not. if you have a 20KM continousely ride, you will found the normal bearings produced great heat. I did tried the bearings heated melt the wheels before. ceramic bearing don’t produce heat.

That’s good info though. didn’t come to mind, my bearings are loosening inside the weels plastic centers. This is probably the reason. Thanks ! But aren’t ceramics fragile to impact ?

ZrO2 is fragile to impact, Si3N4 is real hard

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