Let's see if this works.

Sheldon Brown

I want to see his opinion belt drives.

Put up the crazy old guy signal plz.

I think there are two different discussions people are having here.

1) Merits of chain vs. belt drive as a drive system, isolated.

2) Functionality of chain vs. belt drive on a bicycle...

The first one is a silly discussion because almost no one here (myself included) has the necessary information on the topics (not that it ever stops us from pretending we do)

The second one really isn't much of a discussion because I think all the pros and cons are immediately obvious...

Not sure what my point is since most of our discussions here are fruitless.

As you were.

its aint NJS

Weezy wouldn't ride a bike if it's ain't NJS, he'd say it's ain't proper.

How is the belt joined together?

scotch tape

Here is an entry in The Glossary.

I didn't even think about the issue of looping the belt through the chainstays.

Threads that would be started... Does anyone make a white studded belt to match my white studded belt?

We need to get on making the Sheldon Flatline IMMEDIATELY!

you can see how spot addressed the issue in the picture. there seems to be a small piece in the dropout that is removable.

Yeah i noticed that too. So the belt is one-piece. Seems like theyre doing it right.

no more skiddin? wouldn't this be slip happy all day long on a fix? just seems like the rubber teeth wouldn't hold up well against anything that won't coast...

Given that rubber belts are used as timing belts in engines, also known as the things that keep the pistons and rods nice and separate, I wouldn't worry too much about the belt's sturdiness.

It shouldnt slip. They use belt drives on high powered motorcycles and they dont slip at all.

They also dont suddenly change direction at speed. Im now extremely curious as to what would happen. Id think it would immediately flex and not work too well.

ps - all the high hp bikes I know of, from I4's to vtwins, use chains (drive systems). Ive built and seen high hp cars with timing belts be fine but, as of late, many newer cars are now produced using chains

Yes they do. Except it isnt for stopping power..its launching power. Which on a bike is about 100 times more than the friction of some 23c tire skidding on the street at 20mph.

I know guys with 500whp+ motors that run belts with no issues at all.

The f*ck they do. When a big ol' bike (any belt driven one will do, let's say a Buell. Look it up for details) goes from all out acceleration to engine braking, that's a sudden change of direction. So there. *smiley*

Exactly, thats what im trying to say. No fixed gear skid on skinny ass tires is gonna come even close. I dont care how many MASH stickers you have on your bike.

The Pistons are pinned to the rods
Timing belts keep the pistons and the valves seperate (most of the time)



There is no change of direction (the motor doesnt spin backwards)

True, there is no change of direction. But there doesnt need to be one to exist a transfer of extreme loads. Going from a slow speed to a fast speed with loads of torque is what is happening.
All the power the motor puts out is transferred thru that belt alone to the back wheel of the motorcycle.

so are we talking about doing backwards circles on a bike?

Beyond WOT to down shifting not making much sense *wink*, the belts still going in one direction. Its not a immediate reversal of the belt, its just scrubbing speed through the drive train. You would obviously first brake, rev match, down shift, repeat as need to carry corner speed etc. All of which would lessen the stress.

I never said belts cannot handle massive amounts of stress, I just said "I think it would flex and not work too well" when suddenly thrown in the opposite direction.


Its only pulling in one direction though, it also has a tension system (which this bike does not have). You dont think the belt flexing or skipping teeth would be, at all, possible?

No, not obviously. Because you DONT HAVE TO do that for the belt to survive. There are 1000000 people riding belt drive bikes that have no damned idea how to ride properly and their belts last just fine.
You can ride like an idiot all you want and itll last. I know people that do it everyday.

Harleys and Buells make less than 100hp. If you put a belt on a 140hp motorcycle and take it to the track, it will disintegrate upon launch. Maybe not right away, but it will fail fairly soon. I know because I have drag raced many Harleys, from 80hp to over 300hp.

Even though the bicycle belt is smaller, the design is similar, but I highly doubt this would ever be a problem on a bicycle. Most people are pretty low power, and skidding a skinny ass high pressure rear tire doesn't really take all that much force.

Az