How to make a V-belt drive sheave

[lowracer]

Long term update:
Having built 3 of these 'Rim to Rim' pulley systems & running lots of miles on them, I have a few conclusions.
- None of the wheels has required any truing. I know the added rim strengthens the whole wheel.
- This setup works well front or rear but does limit tire selections to thinner sizes.
Examples- my MTB using 2 MTB rims, the widest tire I can get away with is a 1.5" slick before the belt can rub the tire & cause major problems. I am running a 1.25".
On the 650c wheel pulley, I use the 23c tire (no coices here). On the 700c pulley, I can run up to a 28c which is meaty enough (long lasting touring tire). I'm sure if I shimmed the 'rim to rim' with another rimwall cut off from a donor wheel, I could run wider tires. I'm very happy running the MTB 1.25" slick on the MTB for $9.00 @ Performance Bike.
-Lowracer-

 

[ratdoggg]

I built a double rim years ago for a snow bike and just took the two rims to the welders
and they just put down a bead here and there and it worked great.. The jb weld thing is kinda scary at 25 mph

 

[lowracer]

ratdoggg,
I use JB weld to get the two rims together & get the perfect alignment before drilling a few holes & bolting them together. I havent had any troubles after a few thousand miles on them at over 50 mph.
-Lowracer-

 

[DRJ-Aggie1964]

i just found this thread today 12/18/2016

is anyone out there still doing these modifications? I need to do something similar for a manual wheelchair drive

Wallace.l.johnston@gmail.com

 

[darwin]

Wouldn't electric be a better way to go for a wheel chair? Gas motor might get someone in trouble on one of those.

 

[CrazyDan]

But it sure would be fun xD

 

[Frankenstein]

Wouldn't electric be a better way to go for a wheel chair? Gas motor might get someone in trouble on one of those.

That would probably depend on if the person building the wheelchair needed to be in a wheelchair or not.

Those of us with functional legs enjoy finding ways to make them less functional, oddly enough.

 

[Norswede]

I have now made 2 V-belt drive sheaves for 2 different MB's that I run using direct drive without the need for a jackshaft to get the correct reduction.
One of them is a 26" Mtb wheel & just today I did a 700c (29'er wheel).
- Start with a spoked wheel that you want to add the sheave onto.
- Take another wheel of the same size & remove all the spokes & hub leaving just a hoop.
- Use a hand file & file the non-drive side (left) sidewall of the spoked wheel & one side of the hoop. (rough surfaces are better for the bonding)
- Clean both filed sidewalls with rubbing alcohol & a clean rag.
- Mix up some JB Weld & apply to both cleaned up sidewalls.
- Make sure NOT to line up the spoked wheel spoke holes to the hoop spoke holes. Offset these... (you'll need to drill 4 holes later after its all dry in the spoked wheel between spokes to mount braces).
- Put the hoop on top of the spoked wheel & line up perfectly
- Allow to dry at least a full day or longer to insure a good bond.
- Remove all rim tape before drilling (will need to replace rim tape)
- Drill 4 small holes on opposing sides of the rim (for balance when spinning) between spokes, to mount 4 small pieces of aluminum stock to brace the inside of the two sandwiched rims at 4 points. I use the existing spoke holes in the hoop so I dont need to drill the hoop. Make sure to remove all aluminum drilling burrs
- Run nylock nuts & bolts thru the holes & aluminum stock pieces at the 4 points bracing the wheel/pulley from the inside. This will also allow you to still use rim brakes but wiould need to set them up wider. Disc wheels are better since the braking is done elsewhere on the wheels.
- Depending on rear triangle clearances & hoop width, Tire choices may be limited to narrower tires. I run a 1.25 on the front of my DH MTB Beast. Will probably run a 700x35 on the rear of the other MB.
Take a look at the pics. I haven't done the bracing yet. Just waiting for everything to dry.
The Matrix singlewall rim I found worked out real well as a pulley due to the spoke channel being V shaped to match the V-belt exactly.
If you use 2 deep V rims, you can bolt straight thru the V portion after gluing & avoid the aluminum stock bracing.
-Lowracer-

I need some help. Your expertise seems right where I need it most. I'm making moving art from an old 10 speed bike, and want to use the rear rim (kept in place, but without tire or tube, as a driven pulley that's driven by an electric motor. Will a standard V-belt work? Will the spoke/spoke nuts destroy the belt? how to protect it:? Just starting out. Any help is greatly appreciated. Thanks.

 

[HumanPerson]

I need some help. Your expertise seems right where I need it most. I'm making moving art from an old 10 speed bike, and want to use the rear rim (kept in place, but without tire or tube, as a driven pulley that's driven by an electric motor. Will a standard V-belt work? Will the spoke/spoke nuts destroy the belt? how to protect it:? Just starting out. Any help is greatly appreciated. Thanks.

A couple layers of Rim Tape will do just fine

 

[Norswede]

Then would a standard v belt fit in the rim snugly enough to get traction? Or do I need some other kind of belt? Thanks.