Oops - I've over filed the dropout. Options?

[CycleEye]

I'm working on an e bike conversion from my steel road bike, 1000w 48v rear hub. I sent it to the e bike workshop for tuning and they have inspected the filing I did on the rear drop out to fit the new axle.

Sadly, the mechanic thinks it's suspect, not terrible, but not great, based on the fact that I unfortunately, in my inexperience and limited mechanical and biking knowledge, filed a right angle and created a weak point. It's not so much that I filed too much, more the right angle creating weakness.

His assessment was that it's probably ok to ride for a bit, but it might fail at some point. He was unable to offer much more of an opinion on how safe or otherwise it was, but the lingering doubt is enough for me to want to nip it in the bud.

Other than feeling crap that I messed up, I'm wondering what my options are to fix it. I suggested welding and re-filing, which apparently should work.

Does anyone have any opinions/advice on this? Would really appreciate it.

Pictures here: https://postimg.cc/gallery/8W7qTGV

And a second opinion on the structural integrity would be welcome as well. Thanks in advance.

 

[wheeliepete]

You need to fit a torque arm on both sides of the motor spindle, they will help take the strain off your weakened dropouts. Check the diameter of the motor spindle, I would expect it to be 14mm.

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[vfr400]

That frame was never going to be solid enough for one of those motors. For those big axles, you need a bit of meat around the drop-outs.

It should be strong enough with two properly anchored torque arms at least 5mm thick. I think you need to make your own tie bars out of steel strip and clamp them with heavy duty clamps of some sort - maybe two decent quality jubilee clips or hose clamps per side. Those cheapo jubilee clips that you get on Ebay break too easily. I'd make the tie bars out of something like 10mm x 2mm steel strip about 100mm long with a hole at one end to fit the piece that goes on the axle, then twist it to fit your frame for clamping.

 

[CycleEye]

Thanks. I'm thinking of replacing the dropouts or getting a weld refill and fitting two Grin torque arms.

 

[andrewelectricbike1]

Thanks. I'm thinking of replacing the dropouts or getting a weld refill and fitting two Grin torque arms.

Would be great to see some pics before and after.