Exciting New Project

[sjpt]

My normal is to set a big adjustable spanner to the freewheel tool and clamp it in the workmate; then grab the tyre to turn the wheel. (while leaning on the workmate to stop it turning).
Time before last that failed, but with my son pulling the wheel as well it worked.
Last time it failed and no son to hand, big adjustable spanner hit with a lump hammer did it.

 

[chris_n]

Stick a hacksaw blade through the middle, fix it to a hacksaw frame and cut outwards towards the threads. As soon as you get though the threads if there is any remaining on the black bit cut through that then you have the tension that is locking it in place released and it will unscrew easily without compromising the integrity of the housing. You could use other things like a dremmel if you prefer. You could also use the freewheel/cassette removal trick of clamping the BB in a vice and turning the frame.

 

[saneagle]

What's the measurement of the BB, BTW? Is installing a mid-drive without that thing possible on that bike? If not too wide for a mid-drive, cut and file away enough for a mid-drive axle? Cut four equidistant triangles to fit a square bar into the middle, turn it off using a pipe wrench? Or dremel cut a triangular notch on the outside to fit the hook end of that tool you linked above, holding the tool on using the widget Sturmey suggested? Hope you managethe feat, however you go about it.

It's a standard BSA/Shimano type BB. That piece will come out when the tool arrives on Thursday.

 

[saneagle]

The tool came today. I tried it like in the photo, but I still couldn't shift it with just the tool, so I heated up the BB area to just too hot to touch and tried again, then it went easily:



I've done a trial fit with the new crank-set, which looks so much better than before. I removed both inner rings because I don't want to fit a derailleur and I'm pretty sure that I'd never use them unless my battery went flat. 48T/32T on a bike with 20" wheels is approximately equivalent to 36T/32T (middle ring) on a bike with 26" wheels. I had to use spring washers as spacers to make the nuts fit.





Now I have to make a decision. I have a ready-to-go Q100C that's 328 rpm, so perfect for a 20" wheel at 15 mph. It doesn't have a speed sensor in it, so I have to use an external one. Also, it's a real struggle to get it into the frame because of its width and the frame stiffness. I also have a bare 280 rpm AKM100C, which has a speed sensor in it. I've ordered a rim, but have no spokes yet. It's surprisingly a little narrower than the Q100C and goes into the frame more easily. At 36v, it'll max out at 16mph, but power will ramp down from about 13 mph, but it'll be better at climbing than the 328 rpm one. It also gives me the chance to go up to 48v later for more power and speed if I want it. I'm thinking that the 280 rpm one is a better option, though more work and time to sort out, plus it's marked 250w. I'd have to make a label for the Q100C.

 

[Waspy]

Good effort, I think that threaded bar is just about long enough

 

[saneagle]

Good effort, I think that threaded bar is just about long enough

That tool is pretty good gor the money. It does both sides. The metal is about 5mm thick hard stainless (laser cut). It's a perfect fit on the BB, so no chance of distorting anything.

I'm presently printing a holder for the magnet disc. I could have glued it to the chainwheel, but I wanted something a bit more secure.It'll probably be a couple of goes before I get it right and while I play with the ideas in my head, but then it'll be available for anybody else, who wants to do something similar.

 

[saneagle]

PAS is sorted. The first design worked perfectly. The holder will be retained with four self tappers through the sprocket fixings, and the magnet disc glued to it.