specialgreen

My bike has a Shimano 8-speed internally geared rear hub. It uses a torque washer like this:
Shimano Nexus/Alfine Vertical Dropout Right NT Washer 8R Blue | Bikewagon
It's a beefy 2.5mm thick washer which also keeps the axle from turning.

I'm trying to add an InStep/Schwinn trailer, which comes with its own thin, wimpy torque washer like this
Instep Coupler bicycle trailer connector kit SA074

It has 8 dimples which mate with the trailer hitch plate, in a pressure-fit.

I'm assuming that there's a good reason the Alfine/Nexus torque washer is keeping the axle stationary, and why it's so strong, so I can't remove that washer. But if I place the trailer washer on top of the Shimano torque washer, the trailer's torque washer "finger" is not long enough to reach into the dropout and keep it from turning.

I had a couple of thoughts:

- drill 8 dimples into the Shimano lock washer, to mate with the trailer plate (would need to grind it flat first, as the outside has a raised ring in the center near the axle)
- weld the two washers together
- lengthen the finger of metal on the trailer torque washer: weld a small bolt onto the outside of the finger, which is long enough to reach into the dropout and keep it from turning. It only needs to be stronger than those dimples.
- drill and tap a hole into the side of the shimano washer, and screw a small bolt into it (which will catch the finger on the trailer washer). Or just weld a nut onto the side of the Shimano washer.

fietsbob

they're 2 different things for completely different purposes , the planetary gears have to transfer internal torque to the frame to Function.

that is what the shimano part is for . you can place it inside of the dropout facing out if you wish But they need to be there

(maybe a spacer on the left end of the hub can be removed or thinner so the combined total width is similar.)


the other is just the trailer hitch. You can do as others have and bolt the hitch on with a separate Bolt , someplace else

instead of trying to stack 2 things on the left end of the axle end.. all it has to have is that tube with the pin through It.


If you have metal shop skills you can replicate the functional end the trailer hooks up to, and make the mounting end different.

specialgreen

Sorry, it hadn't occurred to me to look for another braze-on for mounting! Good idea.

I built-up blobs of metal onto the outside of the Shimano torque washer, so that the tang on the trailer torque washer would have something to push against when it tries to rotate. It was easier than drilling/tapping.

CliffordK

A while ago I took some photos of various hitches and frames.

https://www.bikeforums.net/utility-cy...l#post18069408

The simplest hitch was the Bike Friday air hose hitch, welded to the frame.

I didn't have an Alfine bike to compare to. My Nexus bike had brake torsion bar limiting the types of hitches that would go on it. The Burley hitch came close, but would need modification for hub clearance.

The Avenir hitch (shown on the Colnago) only attaches to the chainstay, and would be a possibility, as long as nothing gets in the way of the attachment (won't work with my Nexus due to the brake torsion bar).

However, if I was you, I'd just try your hitch. You should have those anti-torsion washers on both sides of the hub. So, it may be just fine without a left torsion washer. Or, as mentioned, put the torsion washer on the inside facing out.

zebede

My hitch is from instructables web site.
Two U-bolts. Hold (4 bolt) furniture caster with caster wheel removed. Clevis pin goes in empty axle holes. Cost approx.5$