Electric motorbike racing

**Jonathan** · 14-03-2016

Quick update, I made some progress with the titanium shaft this weekend. I almost finished the lathe work:

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I used a CBN tip for the finishing as it was able to take extremely light cuts, so no "hand finishing techniques" required. The tolerance on the part measured above was 50.003-50.015, so I made it to 50.010 as the young's modulus of this material is lower than the steel that fit was specified for, so making the interference slightly greater seemed the safe option (though it probably wont matter in reality).

Next weekend I'll do the last bit of turning on the other end, then it needs a few slots miling and some holes drilling to mount the sprocket.

In other news, we should be getting the new bike frame delivered within a week, so watch this space. Race dates have also been confirmed, so I'll be in Belgium, Germany, the Netherlands, Portugal and the UK!

Originally Posted by Lachlan

Really enjoyed reading this thread Jonathan! Keep us posted on any updates and thanks for all the effort with the pics.

You should check out the "Voltron" bike on endless-sphere.com, made by someone near you (Australia at least).

**Jonathan** · 21-03-2016

Originally Posted by Jonathan

I almost finished the lathe work:

Famous last words ... took me most of last weekend to actually finish the turning:

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I double checked all the diameters now it is off the lathe and it's well within tolerance - e.g. the longest diameter is 0.011mm different from end to end, but the drawing specified up 0.04mm here.
Next step is to mill 3 keyways in it and drill some holes for the sproket.

We also got some new brakes delivered from PFM. Apparently they're really good ... I don't know about brakes.