Belt drive. Why not?

[plugboots]

Looks fun. What is the gearing equivalent to?

It's a 46x26, so the same as a 32x18.

Fill me in, this is a fixed speed set up correct? No variable clutch or anything to provide varying Gear ratio's?

Yes it's a fixed speed, no Rohloff or Nexus internal, but not a fixie.

I don't think it's the worst idea ever, far from it. Anyway, I've broken lots of shit that I've had to run home from, so I will not be carrying a spare belt, and I don't ever do 3 mile repeat loops. My first ride was my typical 15 mile daily ride, and I cleaned everything, and I liked the new challenge. The outside of the belt has a grooved finish, so when I had to grind it over a root it gripped fine. Hopefully it all holds up well.

[grskier]

Speaking of belt drive... am I the only one who thinks this is the worst idea ever?

http://forums.mtbr.com/29er-bikes/ni...ve-869863.html

sawing up the rear triangle... brilliant.

[xyz]

how does a belt drive do in muddy conditions?

[simple]

you can't store them coiled up at all..need to keep them as a big loop to avoid stress zones.

That isn't true. They come in the original package wound up in a smaller loop. Only people i know riding with a spare are the Great Divide racers but most of them don't

[smslavin]

I've ridden my Spot for many many miles with the belt.

Thinking about converting my Spot over the winter. What tools do you need to do the conversion/setup yourself? My rear hub is a CK with fun bolts so I'm good on the back end.

[climberevan]

Does your Spot have a split dropout setup? If so, you just need the belt, sprocket, chainring, and freehub spacers.
Tools: Allens, cassette & bb wrenches.

[smslavin]

Does your Spot have a split dropout setup? If so, you just need the belt, sprocket, chainring, and freehub spacers.
Tools: Allens, cassette & bb wrenches.

Yes it does. Any need for the belt tensioner thingy? Everything else I have covered.

[plugboots]

how does a belt drive do in muddy conditions?

I haven't seem this, but friends told me the cyclocross guys with belts just have the support crew blast a hose at it, instead of changing bikes.

[frorider]

That isn't true. They come in the original package wound up in a smaller loop. Only people i know riding with a spare are the Great Divide racers but most of them don't

How big is the packaged loop?

Review quote:

Like the original Carbon Drive, CT belts are not repairable—the only way to “fix” a broken belt is to replace it—and must be handled somewhat carefully when not installed. Bending or twisting the belt too aggressively will damage the carbon cords inside, and can lead to failure. So far, I haven’t broken a belt (a few riders in my area have broken original Carbon Drive belts), and I’ve had more than a few rocks and sticks jam into the drivetrain. Still, I’d suggest carrying a spare belt if you’re headed out on an epic backcountry adventure.

[climberevan]

You need some sort of dropout adjusters to get the tension right. If you're already SS your current ones should be fine.

Sent from my DROID RAZR using TGR Forums

[simple]

How big is the packaged loop?

Review quote:

Around 4 x 4 inch package

[plugboots]

Still love this thing.
ZERO maintenance for the belt. I'm on a Chris King BB now, as I wore through the original.

[Alaskan Rover]

Less efficient transfer of energy is the biggest drawback to them. That's why they aren't used in the pelaton for racing. Otherwise, cyclists would be ALL OVER them!!! Less weight!!!!!!

[toast2266]

Less efficient transfer of energy is the biggest drawback to them. That's why they aren't used in the pelaton for racing. Otherwise, cyclists would be ALL OVER them!!! Less weight!!!!!!

Totally. If it wasn't for the loss of efficiency, all those single speeders in the TDF would be all over belt drives.

[MagnificentUnicorn]

Less efficient transfer of energy is the biggest drawback to them. That's why they aren't used in the pelaton for racing. Otherwise, cyclists would be ALL OVER them!!! Less weight!!!!!!

Unless you are using an internal geared hub I don't know how would you use a belt drive with derailleurs. Is it really less efficient "energy transfer"?

[jono]

An accurate friction loss comparison seems to be hard to come by. Friction Facts did a test, which was partially published on Bike Radar, but the parts that were published were far from conclusive. They reported losses in Watts, but didn't report the total, which would impact a) how much the losses matter and b) the actual tension being tested. The fact that they found belts with zero preload to be more efficient than chains above 208 Watts indicates a potential problem with the first test (namely, that under full pre-load the efficiency would also change with power, so a single data point is useless) and that for off-road use, where we spend more time under high loads or coasting, a belt could be more efficient.

And that's a comparison with a new chain, not one that sees 100 miles between lubes or has stretched a bit with wear.

Gates continues to say that belts are about the same as chains, for whatever that is worth. When mated with a Pinion gearbox they are quiet enough to hear the gear whine, though. So they've got that going for them.

[Alaskan Rover]

That's true of course about the belt / dérailleur problem. You'd never be able to get 11 speeds with a belt...the belt would certainly be wider than the new narrow chains. You MIGHT be able to get 5 sheaves to fit, though. I don't know...it would be weird! And I guess the derailleur can have sheaves instead of jockey wheels. It seems a round belt would work better around a sheave-enabled derailleur and sheave "cassette". But then wouldn't you have more slip around the main " drive," sheave if you went to a round belt, instead of a v-belt?????

Another thought : slip and loss of energy isn't much of an issue when you're dealing with a 5 HP belt driven system say on a mower or whatnot...you would barely notice it. However, you'd notice even a little bit of loss when you're only a 1/8 HP human driving the system!!!

But for a just hop on/hop off street bike or beach cruiser converted to single speed, seems it would be the cat's meow!! You know how many pant legs of nice khakis I've ruined with grease on my cruiser bike???? Prolly 8 pair or more. And that is WITH the ankle strap...would be even worse without!!!! Or having to look like a dork with your right pant-leg tucked into your socks and it fucks up the crease.. Hahaha

I don't think it would be hard to convert ANY cruiser bike to belt simply if it wasn't for the problem of needing track bike-style rear facing drops. So I guess converting a hipster fixie to belt would be easiest. Would be nice project. Hell, I'd be game just to be free of grease on a rec street bike!!

[plugboots]

Well the way it's worked out for me is the positives of the belt outweigh any negatives of the belt, if you're talking about a single speed or an internal geared hub.

[Alaskan Rover]

I'm stoked on trying a belt, unfortunately none of my present frames have rear-facing dropouts. Would a regular single speed tensioner work instead? Would you be able to get enough tension out of it? Still a bit of a conversion, swapping out the jockey wheel on the tensioner with a proper sized sheave. I guess a belt conversion kit can be had.

I think I'll just find an old frame with rear facing dropouts, instead of messing with a tensioner.

[toast2266]

I'm stoked on trying a belt, unfortunately none of my present frames have rear-facing dropouts. Would a regular single speed tensioner work instead? Would you be able to get enough tension out of it? Still a bit of a conversion, swapping out the jockey wheel on the tensioner with a proper sized sheave.

Are you going to cut a hole in your frame too?

[Alaskan Rover]

Are you going to cut a hole in your frame too?

How do you mean?

Ahhh.....I get ya!!

Yes....a dilemma!! Sewing a belt together like the old-timers did with leather belts?

OR....how about something like this??

[GeezerSteve]

Another thought : slip and loss of energy isn't much of an issue when you're dealing with a 5 HP belt driven system say on a mower or whatnot...you would barely notice it. However, you'd notice even a little bit of loss when you're only a 1/8 HP human driving the system!!!

High speed low torque vs. low speed high torque is apples v. oranges.

[Alaskan Rover]

High speed low torque vs. low speed high torque is apples v. oranges.

That was basically what I was getting at...however when comparing machine to human, it's more like high speed, high torque (machine)vs low speed, low torque (human), comparably, wouldn't it? What is the torque exerted by a Olympic class cyclist at the crank while in an all-out sprint?

[GeezerSteve]

when comparing machine to human, it's more like high speed, high torque (machine)vs low speed, low torque (human), comparably, wouldn't it?

Right, that was my point

[Alaskan Rover]

Right, that was my point

Rethinking your statement...it turns out your high speed, low torque (your average small engine) vs low speed, high torque (your average cyclist or mtn biker) is more accurate than my high speed, high torque vs. Low speed, low torque... because I'd underestimated just how much torque the leg muscles can apply to the crank!