Boost rear hub cut down to tandem 145mm

[mikemelbrooks]

I have narrowed down 142mm thruaxle hubs to fit 135mm qr frame and I wondered if any one has narrowed down a 148mm boost hub to fit a 145mm tandem frame?

[rjb]

I've got a 142mm qr hub which ive earmarked for my 145 oln tandem. Couple of thin washers on the axle would take it up to the size required.
Can't see an issue in reducing a 148 hub to 145.
Keep us updated.

[Brucey]

because of the way through-axles work (ie with 3.5mm of each axle end disappearing into the dropouts), the actual dropout spacing of 'boost 148' is 141 mm. This means that everything important can be made to fit nicely in a tandem, and any proposed conversion will be more about the practicalities of altering the axle length/type in that particular hub, rather than anything else.

[mikemelbrooks]

because of the way through-axles work (ie with 3.5mm of each axle end disappearing into the dropouts), the actual dropout spacing of 'boost 148' is 141 mm. This means that everything important can be made to fit nicely in a tandem, and any proposed conversion will be more about the practicalities of altering the axle length/type in that particular hub, rather than anything else.

Thanks
I have ground down either end of the axle by 1.5mm, a quick trial fit and the disc lines up very well. I could find lots of information on line about the spacing of thru axle, boost and boost plus hubs, but nothing on 145 or 160mm tandem hubs. Like I said I have cut down 142mm thruaxle hubs to 135mm qr, which I have put hundreds if not more miles on, fitted to my winter bike.

[Brucey]

I think it shouldn't be too difficult to make QR axle end adaptors, using Al tube and wood, glued in place. Once the wheel is fitted, the adaptor doesn't have to do much. I also think the axle could easily be shortened and given a nice finish etc using the SG method. The axle could be held easily using a simple studding plus rubber expander type fixture.

[mikemelbrooks]

I think it shouldn't be too difficult to make QR axle end adaptors, using Al tube and wood, glued in place. Once the wheel is fitted, the adaptor doesn't have to do much. I also think the axle could easily be shortened and given a nice finish etc using the SG method. The axle could be held easily using a simple studding plus rubber expander type fixture.

I have a 148 to QR adaptor that I have turned down to 145 in my mini lathe. I really wanted to know if the disc and sprockets would all line up so I wouldn't have space out the disc mounting too much. But I can confirm it all looks good.
https://amzn.eu/d/iDfAZAp

[Brucey]

I suspect that, at worst, you will need to add a few extra spacers to the disc or caliper mountings. I also think that you can do everything required with just a drill, if you want.