Open slot torque "arm"

[anotherkiwi]

I have been wondering about making rear hub motor wheels easier to remove. My current idea is a custom made SS torque plate with an open slot corresponding to the dropout slot (a bit longer of course). Thicker than the average torque arm but with a reserve machined out for the axle nut and slot washer. Just the one for the gear side.

Comments?

 

[Woosh]

this is the torque arm for the rear wheel that we use:

You need an allen key to remove it but it's quite secure.

 

[anotherkiwi]

That is my point. I don't want to have to remove the torque arm/plate to remove the wheel.

 

[Woosh]

the torque arms are there to make sure that even when the wheel nuts are not tight, the motor wheel won't come off.

 

[anotherkiwi]

Hence the longer/deeper slot. And loose wheel nuts? This motor was previously in a steel frame so no torque arms and a slightly file deepened dropout slot.

 

[Deleted member 4366]

That would work, but you'd need at least 5mm. Even the hardened enclosed ones stretch if you have something like a BPM at 30 amps. The other problem is anchoring them precisely. I've seen torque arms like you suggested on ES (self-made). In the days before torque arms were widely available, some guys used a suitably anchored 10mm open-ended spanner.

Another thing you can get is a side-stand that bolts to the drop-out. They have a 10mm slot that matches the drop-out and they're made of steel, but it's not very thick and not hardened - better than nothing though.

 

[D C]

this is the torque arm for the rear wheel that we use:

You need an allen key to remove it but it's quite secure.

That looks to be just right for your XF08 rear wheel kit which I've recently fitted? is it possible to purchase one from you?
Dave.

 

[Woosh]

hello Dave,

If I find them, I'll send you a pair.

 

[D C]

hello Dave,

If I find them, I'll send you a pair.

That's great, I'm happy to pay for them though, just invoice me when you send them.
Order number for my address was 109815, Tony 11391.
Dave

 

[anotherkiwi]

That would work, but you'd need at least 5mm. Even the hardened enclosed ones stretch if you have something like a BPM at 30 amps. The other problem is anchoring them precisely. I've seen torque arms like you suggested on ES (self-made). In the days before torque arms were widely available, some guys used a suitably anchored 10mm open-ended spanner.

Another thing you can get is a side-stand that bolts to the drop-out. They have a 10mm slot that matches the drop-out and they're made of steel, but it's not very thick and not hardened - better than nothing though.

I was reasoning 2 mm stainless + aluminium dropout, combining the strength of the two? The steel is there for the initial burst of torque and the dropout can manage "normal" torque from there on. This is for 26" and 24" hub motor wheels with 250 W motors running at normal power levels. The 24" wheel for the mountains of course so definitely with a motor capable of running cool for long stretches of climbing at reasonable speeds.

For a hot rod BPM I would look at alternative means to attach the beast...

 

[Deleted member 4366]

You hardly need torque arms for a standard rear 36v motor at say 15 amps.

 

[anotherkiwi]

You hardly need torque arms for a standard rear 36v motor at say 15 amps.

Just the one I was going to fit on the drive side. And the motor will be running at 17 Amps so 710 W peak, battery hot off the charger, 612 W at 36 V.

 

[D C]

hello Dave,

If I find them, I'll send you a pair.

Many thanks, I've just to fit them now as "belt and braces"
After many more miles I'm pleased to say I'm still more than happy with the kit, excellent quality and excellent service from Woosh.
Dave.