Pulley for pnuematics that contain a bearing

There are more and more builds that are reaching speeds of 40mph+ and most of them are on urethane that have a wheel pulley that contains a bearing for precision alignment. I’m wondering if there are metal pulleys that also contain a bearing for pnuematic tires such as @psychotiller 's six shooters, @Kug3lis 's hubs, and the trampa superstars.

The goal here is to have a precision wheel hub and pulley that is true and doesn’t start wobbling and killing people when going at downhill speeds

I think it’s less of an issue with pneumatic wheels, specifically the machined metal ones, since the bearing seats in the wheel itself are much more robust and more precise than the ones in plastic wheel cores, and thus can support higher loads with more precision.

I haven’t used Trampa or Kug’s wheels, but the sixshooter wheels at least have very close tolerances between the pulleys and the mounting hardware, which results in good centering without a pulley.


I haven’t seen the six shooter pulley before, how does it look like? I literally cannot find a picture of them anywhere.

Thats a one point that I did not take account to. I’ve seen high speed carvons and @Deckoz 's monster evo and realized that everything was extremely precise and have no room for error. Maybe the plastic wheel hubs are making me paranoid of pulley vibration.

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The sixshooters use VersaPulleys. https://www.vexrobotics.com/htdversapulley.html

You can get rid of any potential wobble by using counter weight pearls. I have used them in my 3D printed hubs and have virtually no wobble at all.

I think this is what you’re looking for.

Hey there.

So with hubs like superstars and sixshooter. You have a precise hole for the screws that clamp together the hub halves. Basically wheel hubs, should act like Kegels.

Kegel pulleys without a bearing do not have a tendency to walk, because the holes in the hub are circular, and go “straight through”.

Really the only wheels I’ve seen “pulley walk” on where it can go out of center, is Flywheel style wheels. The openings in the coreare of shaped, which allow the pulleys and bolts to “walk” out of true with vibration.

Kegels style cores(urethane), and wheel hubs(pneumatic) shouldn’t ever experience pulley walk. So I think you are fine. Justified in your concern, but I believe it is a non-issue.

The bigger issue with pneumatics is balancing your tire :wink:

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On SixShooters the pulley standoffs are machined on the back side of the wheel. The versapulleys screw directly into the machined standoffs. There is no pulley walk. The only issue I’ve seen with wobble is misaligned halves, lumpy tires, and then the biggest issue is valve stem weight. This can be remedied with beads as mentioned above. Or weights which will likely be machined into my hubs soon.

Also, we’re currently building a luge to high speed test sixshooters. We will know how they feel at 60mph fairly soon.


On pneumatic like MBS Rockstar you have to be careful to not over torque the bolts… Go slow and you can use the bolts to balance the tire on the wheel.