Rear belt drive?

Curt,
I was just reading over the article and ran across this statement...

"To install
the belt, it will be necessary to cut the
lower left rear fork, as shown in Fig. 6. A
strip of 16-ga. tin, bent to a sleeve and
bolted over the cut, as detailed, repairs the
break and permits easy removal of the belt
at any time. "

Huh? They are cutting the chain stay so the belt can be installed, removing a section of it and the "repair" is a piece of tin to cover up the gap. Is that right? Well, that's no good. Am I reading this right?
SB
 
Yes the hart beat of america sorta, That and the old generator friction builds. They took a old car geenerator and cut the side out of the case welded the mount on the top stays run a belt back to it. it was spring loaded with a rod to raise and lower the generator. The motor set up front between the frame. Many of them built,infact i have a old rusty one i may restore...................Curt
 
silverbear said:
Curt,
I was just reading over the article and ran across this statement...

"To install
the belt, it will be necessary to cut the
lower left rear fork, as shown in Fig. 6. A
strip of 16-ga. tin, bent to a sleeve and
bolted over the cut, as detailed, repairs the
break and permits easy removal of the belt
at any time. "

Huh? They are cutting the chain stay so the belt can be installed, removing a section of it and the "repair" is a piece of tin to cover up the gap. Is that right? Well, that's no good. Am I reading this right?
SB
Click to expand...

Yes that's what they're suggesting Silverbear, - though if you were to use a link type belt or a belt joiner you wouldn't have to do that. Otherwise I've always thought that was a cool old plan :)

Curt, - I like the sound of those old cut down generator based friction drivers. I wonder why I haven't heard of them before. Now of course the problem is finding an old generator that somebody hasn't decided is a 'collectible' and is therefore wanting a fortune for it.
 
Does anyone know the diameter of the drive pulley on a Whizzer motorbike?

Anne, you point out an advantage to the link belt in not needing to cut the frame (and leave it open) to access the belt on that bike in Curt's article. We need some real life experience to know if belt slip is an issue. Wish one of our Whizzer riders would try a link belt just to see. Frame modifications on that bike are substantial to make room for the driven pulley, a second rim welded directly to the rear wheel rim, being of the same diameter. When that article was written the additional rim would likely have been for a balloon tire of 2.5" width. I wonder what difference it might make using a narrower rim of say 1 3/8" width. Might be that no frame alterations are necessary.

Using this article as a kind of model in how to do it might not be such a great idea. Cutting the chain stay and leaving it cut open in order to change the belt makes me question other things as well. That chain stay is there for a reason. If one of the builders on our forum did that the alarm bells would be ringing and for good reason.
I also wonder at the gear ratio with a 3" drive pulley and roughly 22" driven pulley (what the additional rim comes to without a tire on it) which is a good 7" bigger than a Whizzer sheave. That makes the ratio about 7-1, doesn't it? Yet with a 1 1/2 hsp engine the author claims a top speed of 35mph. Maybe, so. But I do think that a person needs to be objective about that article. Could be the author was mostly selling a magazine story which would have a lot of appeal. All these years later it got our attention. Could be the builder made a Frankenstein bike. I keep thinking about that chain stay with a chunk missing... on a bike that now has a motor propelling it down the road at 35mph with one brake, a coaster brake, to stop it. Hmmm...
SB
 
Intrepid Wheelwoman said:
Information on that isn't easy to find on the 'net SB, but it looks like it's 20 inches.
Click to expand...

Not the driven pulley on the wheel, but the pulley on the other end of that belt... should tell us something about the gear ratio in relation to belt slippage. Whizzer must have figured out a good size for each pulley through many years of production.
I have a Whizzer sheave on my kindalikeawhizzer build and it is 15 1/2 inches diameter. Curt says that a 20" bicycle wheel has a rim diameter of roughly 16".

I wonder, too, what the pulley sizes are on the old Simplex servi-cycles. They were belt drive, too, weren't they?
SB
 
http://motorbicycling.com/showthread.php?t=30085

Look at post #4 on this thread link it says : small 2.5" pulley on the flywheel
==================================================
05-24-2011, 09:03 AM
Quenton Guenther's Avatar
Quenton Guenther Quenton Guenther is offline
Dealer

Join Date: Feb 2008
Location: Outer Banks of North Carolina
Posts: 687
Default Re: Whizzer NE-5 belt tensioner headache!
Hi John,

I sent you a reply to your email. I also included a few pictures. I think if you simply shorten the bushing [file or grind] the bearing will "clamp" tighter on the mounting plate.

The manual & automatic clutch have the same size pulleys, and the 15285 automotive wedge belt will also make the manual work better.

Due to a design flaw by Joe Lin [Tiawan] the original clutch arm isn't the correct length, and makes it very difficult to make the manual clutch work smoothly. It is either tight and the belt doesn't slip when stopped, or loose and allows a stop without "grabbing", but slips at higher speeds. Sadly a 29" belt is too long, and a 28" belt is too short [a 28.5" belt is needed]. He also wasn't smart enough to understand that notched belts were made to work with small pulleys. The vintage Whizzers used a AX26 [28" long] notched belt, and the clutch worked 100% correctly. He elected to use a cheap fractional HP belt [4L290] and it doesn't bend well around the small 2.5" pulley on the flywheel. The cheap FHP belt also stretches, and easily glazes.

Hope this information is helpful.

Have fun,

================================================

Maybe this is the information you needed.

I also looked at Memory Lane Classics, but the size is not listed. Maybe call as they were nice and talked with me when I was pricing Whizzer clone sheaves.

I ended up buying on Ebay my sheave but it was a bit needing of cleaning the weld seam that was rough. Also I drilled out the clamp threads and used my own stainless steel hardware with a bit more effort an cost.

2.5 inch is a bit smaller than the belt type centrifugal clutch Max Torque makes, I bought for my build which is 3.2" diameter.

http://www.maxtorque.com/html/pully_clutch.html

http://www.mfgsupply.com/4-865.html

MT
 
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MT,
Excellent post with a lot of valuable information in it. Quenton Guenther knows his stuff. Thank you, sir!
SB
 
My 2" pulley is no longer being use between the top and bottom jack shafts. I use a chain instead. Maybe 3" should be the smallest used and I got the cogged belt to help make the tight radius bend without as much heating and fraying.

Below the link to the adjustable diameter pulley 3.5" max. I got a cogged belt that I use with it and it connects to the Whizzer clone sheave. I have it set under the 3.5" by a small amount, probably 3".

http://www.grainger.com/product/CONGRESS-V-Belt-Pulley-1L844

MT
 
The bolt onto sprocket I'm not sure exactly how, but the sprocket is on a flat plane most likely.

The spokes to clip to just please consider this:

The spokes themselves that span between the hub and the rim make kind of a cone shape on both sides.

I did have sort of an issue when I made my wood (coated with resorcinol glue) sandwich to connect a pulley to the spokes.

I looked to see what the inner diameter of the 16 inch pulley is for what you were looking at.

This was because if the pulley is planted onto the spokes, it will be some distance away from the spokes where the belt is riding in the groove of the pulley. What that means is the drop outs must be spread ever so much more for the assembly to fit.

Guessing it is about 1/3 of the 16" or roughly 5" inner diameter.

Anyway, I am not sure if there is something that you have that accounts for this, but my past washing machine pulley worked, but only after I got it to place the edge of the pulley as close to the spokes as possible. Now since it was too weak a metal (aluminum), I already replaced with a Whizzer clone sheave made of steel.

The pulley I used had its own type of spokes that I bent at an angle to match the angle of the wheels spokes cone shape. They did not break under the strain, but the pulley groove itself did. So I ended up not a complete DIY rear belt drive, but that is my story.

My past wood pulley sandwich on my thread: Page 9 post #90 picture.

http://motorbicycling.com/showthread.php?t=29678&page=9

More DIY the better, though I offer what I was confronted with with my method of building. Hope the info is useful.

MT
 
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In the interest of seeing if this 16" steel pulley will work, Curt is going to pick it up for me at his local Fleet outlet. He is also picking up a 3" weld on pulley and will be making the modifications on my old Tecumseh clutch, turning it from a sprocket clutch into a pulley clutch. (In return favor, Ill be upholstering another old seat for him.) We talked about the frame clearance issues and I'll be doing some measuring today.

It is a little early to speculate, but I think he will be cutting down part of the pulley from the center out since the pulley is going to be bolted to the old driven sprocket. The pulley will be bolted to the inside edge of the sprocket to draw it a bit closer to the spokes and away from the seat stay and chain stay. Adding spacers is another possibility. Giving the belt clearance from the frame is an ideal. Big sigh if major modifications are needed. A plus is that the sprocket the pulley will be mounted to is a full 10" in diameter and is substantial. It, in turn, is mounted to a Manic Mechanic clam shell hub adapter which can be adjusted laterally on the hub. This, too, gives opportunity to draw the pulley in closer to the wheel.

If after all is said and done, tried and if found wanting, I can always resort to using a sheave attached to the spokes. Just in case, I'll be on the lookout for a 20"wheel with a narrow tire, 20" X 1 3/8" (with an actual rim size of 16", the same as the pulley from fleet and the approximate size of a Whizzer sheave). I have a set of Whizzer spacers and clips which should work attaching it to the spokes. So there is a backup plan and I could have saved some money ($26.00) by just going this route. But in the interest of finding out how this big pulley bolted to sprocket will work I had to give it a try. If it works out it should open up some belt drive options for others on a budget.

Curt will be converting the clutch this winter and I'll ask that he take some pictures along the way. Material costs for the conversion should be around $7.00 for the cost of the weld on pulley. And he may be cutting away part of the center from the 16" steel pulley before sending things back to me. Once I have the big pulley in hand I can mount it to the worn toothed 10" Manic Mechanic sprocket with bolts. Hopefully by then winter will be losing it's iron grip in northern Minnesota (20 below zero the last few nights) and I can do some work directly on the bike. It would be nice if when the last of the snow melts I can fire up my American Flyer and give my "new" belt drive a test run. Woohoo!
SB
 
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Measure Twice,
You are the first I know of to try using a big washing machine pulley as sheave. If the metal in it had been pressed steel I'm guessing it might have worked out. The 10" diameter was also a limitation and until yesterday's find by Curt the best I could come up with was also 10". But you were thinking along the right lines and get the pioneer award of giving it a go. What I'm about to do is "giving it a go, part two". By the time some one else does part three we may have figured it out and worked out the bugs. Interesting thread, sir. I appreciate your work.
SB
 
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