Motorcycle Wheel Balancing Cradles

Background

I've been using automotive axle/chassis stands to balance my motorbike wheels (with the axle simply resting on two stands).  I thought I'd design a cradle that sat on top of my (SuperCheap Auto) axle/chassis stands that would lower the resistance to rotation by having the motorbike axle rest on two pairs of 608 bearings (in-line skate bearings).

My brother uses a gap between two of his workbenches to balance his wheels.  I designed different (simpler) cradles for him that simply sit on flat surfaces rather than over the top of automotive axle/chassis stands.  His are the ‘Plain Mount’ versions.

Versions and Onshape Document

I've included the STL's of both versions along with the STEP files for both versions if you want to play around with them at all.  

Both versions of the cradle are designed with a ≈25mm diameter motorbike axle in mind.  The version that sit over the top of the SuperCheap Auto (Australian store) chassis stand have a 43 x 76mm recess to fit nicely over the stand.  If your chassis/axle stands have a different size top, you can copy my Onshape document and simply alter the #PlinthWidth and #PlinthLength variables to suit.  The design will update automatically.

There are plenty of other self-explanatory variables in the design you can alter to your heart's desire if you so wish.  My design can be found at:

https://cad.onshape.com/documents/7596608a5ccafe0f3c5e5ac4/w/b6883706cfd8c9991e206aec/e/107db2d751bd516cd5c3ff20

Printing

The cradles are a solid design.  Motorbike wheels aren't that heavy.

My print suggestions are:

• You'll need to print two of them ;-)
• Material: PETG or PLA
• Perimeters: 3 or 4 - however you like to roll
• Infill: 20% Cubic should be good
• Layer Height: 0.2mm worked well for me
• The Stand Mount versions will require support material.  I used Snug, Honeycomb infill from the build plate only.
• The Plain Mount version does not require any support.
• The included 3MF file has the settings I used to print the Stand Mount version on my Prusa XL.

Extra Materials Required

• You'll need four 608 bearings (8x22x7).  I used ones without rubber sealing rings to keep the rotation as free as possible.
• You'll need four M8 bolts and nuts.  My stand version used 65mm bolts, whereas the plain mount version only requires 50mm bolts.

The nuts need only be done up to a light finger tightness at most.  Tightening them any further does absolutely nothing for the function of the cradles.  To be honest the nuts only stop the bolts falling out while the cradles are being stored/retrieved; they don't actually do anything during operation.