Advice for shallow dropouts

[tomaquet]

I've recently installed a 350 W rear-wheel motor and I'm a little concerned about the shallow dropouts (aluminium frame). I had previously gone out for a test-run and the wheel came out of the non-drive-chain side dropout (luckily the cable and myself were not damaged).

I examined the dropouts again and realised that the axle was not completely seated (drive-chain side) - I filed a very small part of the dropout so that the axle seats as deeply as it can (see photos). But the torque washers still don't look like they are sufficiently supported in the dropouts. I also think that maybe the bolt nuts to secure the wheel were not as tight as they should be.

I bought a couple of cheap torque-arms (jubliee-clip style - before reading that they are generally rubbish) and so far have attached one (on the non-drive-chain side).

Do you think this is enough to stop future axle spin-outs?
Should I attach the second (jubilee-clip) torque-arm?
Should I buy and attach a better torque-arm?
Should I file the dropouts (and hanger?) to make the axle seat deeper in the frame?

I know it's not an exact science but all thoughts welcome!

Thanks, T


Photos to show the current setup (the bike is upside-down in all photos):

http://imgur.com/9iKPclV

http://imgur.com/NP98Pgo

http://imgur.com/QqgUEcn

http://imgur.com/fr3dNFW

http://imgur.com/WbY64FE

https://i.imgur.com/iQl7s3o.jpeg
https://i.imgur.com/jlyRvB9.jpeg
https://i.imgur.com/Ll9odLy.jpeg
https://i.imgur.com/F0orT0a.jpeg
https://i.imgur.com/aWRSqV3.jpeg

Images folder: https://imgur.com/gallery/shallow-dropouts-ebike-3tvJ1sU

 

[Benjahmin]

Yes, dropouts are way too shallow. I've used these torque brackets on several conversions. However they do rely on havinf either rack or mudguard fixing points.

https://www.amazon.co.uk/hammer-engineering-Ebike-Heavy-Duty-Torque/dp/B09NRYP9TW

From what I can see the frame looks a bit weedy, the whole of the flats need to be in the dropout.

 

[matthewslack]

You look to have plenty of axle length to work with, and a fairly large flat area around the dropout.

I would make my own anti rotation plates from say 4mm or 5mm aluminium sheet. A close fitting axle shaped hole - not a slot, a hole, much stronger - and then drill and bolt to those flat areas. Probably M5 minimum bolt, and might have to be countersunk head to keep clearances OK.

 

[saneagle]

You have plenty of room to file/grind the drop-outs a lot deeper, which you should always do if you can.

 

[Nealh]

Nice drop outs one can easily take 4mm out of them to sit the axle lower, filing needs to be good and tight though then add a one piece custom torque arm to the LHS .

 

[tomaquet]

Thanks for all your comments and suggestions.

I think I'll file the dropouts 4 mm and then look for a better torque arm solution. Making my own custom torque plate is a little difficult as I dont have the tools available although obviously that would be the best solution.

 

[Nealh]

One doesn't neccessarily ned to take out 4mm , it was just a comment I made looking at your pics.
The depth you need depends on if one is fitting the tabbed washers and wanting the tab to sit in the drop out.

 

[tomaquet]

I took out maybe a bit less than 4 mm in the end - just enough for the torque-washers to sit in the drop-out. The axle sits deeper and more securly now. I was wondering if was possible to flip the the torque-washers but decide it was better to have the axle as deep as possible instead.

 

[Nealh]

One can flip the T washer if one wishes, all that matters is all of the axle flat sits in the drop out .