12mm to 8mm adapter for MBS rockstar hubs on caliber trucks?

Has anyone tried this?

As we know, most AT hubs have a 28mm bearing, which is commonly reduced to 12mm, or 9.5mm for trampa, mbs, evolve trucks. There is no 28mm to 8mm bearing.

But what if we were to use a 12mm to 8mm tube between the bearing and axle? Ensuring that the length is proper fit?

Something like this, cut down to size: https://www.grainger.com/product/GRAINGER-APPROVED-2m-Seamless-316-Stainless-4NTJ9

Am I off my rocker? Is there a reason this sort of conversion doesn’t exist?

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Those tubes are usually not very pricise7round and the OD can be slightly oversized. the Id might be slightly to small… How do you want to cut a nice thread on it for the axle nut. It has only 2mm wall thickness and not very sturdy. There are more elegant ways to do that. LB-Trucks are not wide enough, so you still face the wheel bite issue.



You need to make them from a solide bar.

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There are a few options for 28x8 bearings.

Also, the easiest solution is to order Evolve hubs which take standard 22x8 bearings and will work with pulleys made for the mbs rockstar II as well as any of the mbs tires.

Evolve AT wheels take 22mm bearings? I thought that was the limitation with using them? That would simplify everything.

Yep, order a set of the wheels and they will slide right on 8mm axles. However,you will likely need something like @torqueboards 218mm trucks to prevent wheel bite. That’s what I’m running and love it.

are you using the pulley that comes with them as well? the 66t.

And what belt/motor mount did you have to use to make it work? I’ve got TB’s 218mm trucks, but I’m also running TB’s standard motor mount for ABEC wheels.

I ordered two of the TB reverse mount plates and mounted my @JLabs 6374 at the end of the deck. The whelks I bought came off of an Evolve so the pulleys came with them.

Ah, got it.

Whats your motor pulley size? and are you just using the belt that came with the AT kit?

66t wheel and 25t motor. I ordered new belts from Amazon.

Wow your top speed is insane high.

To be honest this board scares the shit out of me!

Do you have a build thread for it? I’d love to see its specs.

I need to make a build thread.

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