Custom Dropouts and torq arm

Hi,

Whats the best way to get my axle fitted securely. I don't the way the axle sits and it's been fine with 2 torque arms but I'd like to get a custom part made. Anyone know of someone I'm in the UK that could do it?

Should it be made of aluminum or steel? Also the problem is that if I go deeper into the dropout the locking nuts and washers will hit the frame. I would also like to incorporate a torq arm into the disk brake mounts (if necessary). I have to make new dropouts on both sides. Any experts out there as I am new to this.

That's straight up goddamn dangerous mate. Close your eyes and imagine it starts bumping loose-next time you twist the throttle the shaft will want to spin counterclockwise. It'll push against the left side of the dropouts towards the front, pushing the back of the shaft against the opposite edge of the dropout. This will force it down and allow the shaft to spin out and it'll bump the thing out of the frame and send you flying. That's completely screwed. Here's something you can do to make half decent torque arms;

Get a lawnmower blade with 10mm channels cut into the side;
On the inside edge where the center bolt hole is cut out a square from the center to the outsides so you have two square pieces looking like this: |U|
Throw the pieces on the shaft and using a hose clamp around the chainstay and seatstay fix the arm to the frame.

Crappy solution but it will probably last five hundred miles. Godspeed.

If you search for threads with "torque arm" in the title, you'll find quite a lot of ideas on how to make something to fix this. There may also be people selling something that will work, rather than you having to custom make it on your own.

I'm not sure if I'm seeing what I think I'm seeing. It looks a lot like you have an alloy frame, and a steel plate that bolts on with the two allen bolts has the dropout.

The solution is fairly simple, but requires cutting metal Get some steel plate, and make a new dropout plate that positions the axle just a bit lower, or rearward, and includes some more space on the plate for bolting on a torque arm, which likely will also have to be custom made. Two plates of course, one on each side. The new plate will of course have much deeper dropouts. If the bike is not that high powered, just good strong steel dropouts will hold the motor.

Though more difficult, it can be done with simple tools, hacksaw, drill, file. But a small grinder would beat the hacksaw.

It looks like your disc caliper mount is part of the plate, to make the new one fit clear of the frame, it might work to relocate the axle slot an inch to the rear, rather than down farther.

Thanks for all the responses.

4sken: I am asking about custom dropouts to fix the issue as I am fully aware of the danger. It's been fine for 50+ miles already but I want a permanent solution. I will look at your idea though.

amberwolf: I've looked for replacements but they all have the same problem in that the original dropout isn't deep enough. Searched the forums and no-one is selling anything similar as it's a non standard dropout so I thought custom would be the best way to go.

dogman: Alloy frame, steel plate on dropouts. Yes I came to the same conclusion about having a steel plate. Is there anyway to incorporate a torque arm into the steel plate? By securing it to the frame anchor?

I've uploaded a better picture so you can see the layout.

Also I don't have the tools unfortunately and am happy to pay someone to do it as it's probably about the same cost.

Edit:

I removed the dropouts and scanned them. Definitely not going to fit even if I drill out the dropouts deeper. As dogman dan has said looks like I need to make the new dropouts with the axle plate to the rear. I don't think I can do it myself as there are channels that the dropouts follow that I couldn't machine, ie sliding dropouts.

Edit 2: SO it looks like it's going to be steel dropouts with a clamp on the axle. Any ideas how to make it?

OK, all clear now, I just wasn't sure the brake mounts were part of the plate.

Here's what I'd do. By flexing out on the aluminum frame some, you can make your plate out of thicker steel than you have now. 3/16ths thick or so. 1/4 might be too thick. Then you don't need a torque arm at all unless you plan on more than 2000w or so, like 48v 40 amps.

The new plate will relocate the axle at least 1/2 inch to the rear, allowing room for a deep axle slot, and a large nut, washer, or torque arm.

For more power, you can add more metal to the rear, so that TA you have now can simply bolt to the plate. No need to attach to the frame, the frame will be fine with the existing two bolts that attach it. Just keep the axle from rotating in the plate.

If you want an axle clamp on your plate, here is one cheap and simple way to do it. You'd have to move the axle at least an inch to the rear to do something like this.

But I'd say just bolting on your existing TA, to a thicker plate, would do you fine for up to 100v, 40 amps.

That's exactly what I needed and thought. My motors is 48v less than 1000w so no problem there. I can bolt the torque arms to the brake mount. The problem is though the dropouts are sliding dropouts. As such they interlock with the frame and this provides a lot of strength. A flat plate won't interlock with the frame. Any ideas how I can have those sliders on steel plate?

Edit:

So I am going to have flat steel plates made and then have the holes tapped. Also I will have 2mm steel plate to make the ridges and have them welded on or bolted. Are derailleur hanger threads standard? or backwards or something special?

Oh, I don't know how that plate looks.

Here's a possibility, weld more plate onto your original plate. Weld edge to edge, then maybe back up with more metal spanning the edge to edge weld. That span would weld to the existing dropout on the plate.

But if you can duplicate the original plate good enough, then do that.

You can do it, with some creativity.

Just wanted to let you know I think I found someone who can fabricate it. The original plate is aluminum so didn't want to weld etc as the cost would get really high. Thanks for all your help though and I'll be moving it an inch back as you've suggested.

To anyone thinking of paying someone to do this, it's expensive, around £200 or $300-$400

Ltc433 said:

To anyone thinking of paying someone to do this, it's expensive, around £200 or $300-$400

Click to expand...

I hope you told him to take a long walk on a short pier. I could get it done at a machine shop for $20-25 just a 5min walk from my house, and that's proper clamping type dropout plates. For $300-400 plus shipping you can get a complete dual suspension ebike frame with large encloased battery bay..

John in CR said:

hope you told him to take a long walk on a short pier. I could get it done at a machine shop for $20-25 just a 5min walk from my house, and that's proper clamping type dropout plates. For $300-400 plus shipping you can get a complete dual suspension ebike frame with large encloased battery bay..

Click to expand...

Or make your own frame for 50 and spend the rest on either 'moar voltssss' or just a line of cocaine; either way, buying frames is expensive and you can build one in the time it takes to ship-If you own a welder. Hell, if there's a machine shop around and they have a pipe bender they can make you the main frame out of a single long piece folded over. Very strong.