Topic: Belt Drive.. for Honda CB 750

[754]

I need

dia of front pulley including flange

width of belt and OAwidth  of pulley

c to c distance of pulleys ( centre to centre approx)

[Ibsen]

I'm pretty sure someone on this forum can help you out:

http://www.armbell.com/forum/index.php?mforum=kz400

[754]

Took a quick look, thanks. I did see your name come up on there.Maybe I can go in as a guest or put the Questions to the moderator.

It did answer 1 Q, the gearing is what I need.

But I will have to fill in more info.. it looks like if it is long enough or can get longer belt. I think I could get a belt drive on a CB 750!! Man would that ever be smooth!!

[Ibsen]

Well, since I'm one of the mods there I think that should be possible.

There were two different lengths used for the belt on the 440, a 125T and a 129T belt. The reason is that there were different sized front pulleys, a 22T and a 24T. The rear pulley have got 4 mounting bolts, while the front pulley have got splines to fit the outgoing shaft from the transmission and it is held on place by a large centre nut and a splined claw washer. The splines on the 440 outgoing shaft are not the same as on my CB650, but I can't tell if the CB650 and 750 are similar.
The belt isn't very wide, since the 440 came in both a chain and a belt driven version, and the only parts that are different are the belt, the pulleys, and the belt guard. And a security chain guard inside the engine chain cover was removed to make room for the front pulley.

[754]

So what i really need is dia & width of front pulley and centre to centre distance...likely a bit shorter thann a CB 750.. but I hope not.
 Spline not a problem, any idea what both pulleys and belt are worth?? Do they ever break??? What is belt width?

[Sam Green Racing]

754, this is  but not a very bright idea

The rubber band might be cheaper and weigh less than a chain, but the pullies will be more expensive and heavier than aloy sprockets.

You are going to need several sets because you can't run at Bonneville on drag race gearing. (more cost)

Also have you thought what will happen when we are on your sidcar outfit (I take it you are still looking for a passenger) at Bonneville.
With a chain, any salt that gets in the vicinity of the chain and sprockets will be flung through the holes in the chain.
With a belt, it could become trapped between the pulley and belt causeing the belt to snap.
I don't want a slap on the arse from your broken rubber band

Real cool idea though

Sam.

[754]

Not on that bike, just an idea I had kicking around for touring..

Not doing it right now, but looked into it and can do it by the looks of it.. has to be a short frame though..

 my other bike runs a 6 over swingarm..may cut it back an inch or so..

[fuzzybutt]

set up properly a chain will have less of a parasitic drag on the drive line = more power to the wheel

[Ibsen]

I can ask around and get the measurements if you want to.
Btw, these parts are very expensive. I checked the price from Bikebandit. The pulleys and a 125T belt will cost you approx $650. With the 129T belt it will cost you close to $800. The 24T front pulley are no longer available btw.

Rubber belts last for a very long time, and are less troublesome than chain and sprockets. A friend of mine put 60 000km on his Buell Lightning without any problem with the belt.

[754]

Just a basic measurement would do, even within 1/4 inch. I think though bcause gearing is so close to thr CB750 I can figure it out by number of chain links in a standard chain.

Yes, belt life should be very long, should factor the price of at least 3 chains and a set of sprockets for a real comparison.

But I think the silence and smoothness would be nice..

[Bodi]

I think the belt is very intolerant of changes in distance between the pulleys, and that belt driven bikes have to be designed with this in mind, essentially making the swingarm pivot as close to the sprocket axis as possible. The 750 chain slack changes a fair bit through the rear suspension travel, fine for a chain but I don't know about a belt.

[Ibsen]

754 I will try to get the info you need.

In the mean time:

http://www.bikernet.com/garage/PageViewer.asp?PageID=358

[754]

Geez man, I am  so sorry to hear of his passing..