2026-02-09

Last modified: 2026-02-10 15:20:32

Car rear wheels

The new wheels have arrived! They are 17" pit bike front wheels with 70/100-17 knobbly tyres.

There is a flange intended for bolting a brake disc to, it loosk to have a 76mm diameter spigot and 4x M8 threaded holes at 100mm PCD.

The wheel bearings are extremely bad, I can rock them back and forth but can't make them do a full revolution, it's like the spacer tube is too long and it was pressed in by the outer race and the balls are binding on the races, or similar.

It's not clear whether I'd rather put the taper lock hub on the "inside", and have to inconveniently reach in with a spanner to tighten the bolts up, or put the taper lock hub on the "outside" and have it look potentially ugly.

The distance between flat surfaces on the hub faces is 92mm, plus 2mm for the spigot.

I think the plan will be:

• knock out the bearings
• turn down my shaft spacers to suit the bearing bores (34mm?)
• check that the axle will fit through - dremel out excess if not
• knock in the shaft spacers in place of the bearings
• make up an adpter to attach the wheel to the taper lock hub

Since the PCD is the same, we can reuse 2 of the existing taper lock hub bolt holes, bung up the other 4, and drill 2 new ones. Then make an aluminium spacer to span the gap between the flange on the taper lock hub and the flange on the wheel, with 4 clearance holes, and bolt through the spacer.

Other ideas?

https://www.geminikarts.co.uk/product/steering-wheel-adaptor-plate/

GH Cyclekart wheel adaptor plate 4 mm Stainless steel 90 mm square, this allows the a 3 studded mono hub to fit on the rear axle and then bolt onto the 4 holes of a pit bike wheel.

This adaptor plate is practically free, I may as well just buy it and save myself the bother of making it fit the taper lock hub. I already have a mono hub coming that I am planning to use to mount the axle sprocket, so can test it out with that.