Rear dropout - seeking advice

Hi,

I came across a deal on a rear hub wheel I couldn't pass up and I'm considering installing it on my Santa Cruz. However, I'm not crazy about the idea of modifying the frame to fit the large axle in the rear dropout in case I change my mind down the road (no pun intended). Any thoughts or suggestions on solving this that doesn't involve elongating the slot in the dropout?

You could buy an inexpensive used frame and move the components from the Santa Cruz over to it..

You might try drilling and tapping a hole on the flat part of the dropout and using it and the bolt holding the derailer to hold a slotted plate that would keep the axle from spinning out.Do it on both sides to be safe.

RunForTheHills said:

You could buy an inexpensive used frame and move the components from the Santa Cruz over to it..

Click to expand...

I have another (rigid frame) bike that will definitely work, but this (full suspension frame) would be so much more fun. :wink:

nicobie said:

You might try drilling and tapping a hole on the flat part of the dropout and using it and the bolt holding the derailer to hold a slotted plate that would keep the axle from spinning out.Do it on both sides to be safe.

Click to expand...

Yeah, I think I better give up the ghost on using this bike. The picture I posted is the disk brake side, and I think a plate fabrication like what you described might be feasible on this side, but the other side where the derailier is has a removable dropout, and I think it would be near impossible to do something on that side. I guess I'll use my rigid frame.

Make some torque plates that bolt to the dropouts / brake mounts / etc there, that have just the double-D axle hole in them (exactly the same size as the motor axle; not a slot so you slide them on the motor then bolt the assembly to the bike) placing the axle just just below or behind the existing dropout slot. If you need a derailer or disc brake caliper mounts you can add those to the torque plates in the appropriate spots.

See The Torque Arm Picture Thread for examples. (also just look up "Torque Plate(s)" in general on the forums)

rick_p said:

Hi,

I came across a deal on a rear hub wheel I couldn't pass up and I'm considering installing it on my Santa Cruz. However, I'm not crazy about the idea of modifying the frame to fit the large axle in the rear dropout in case I change my mind down the road (no pun intended). Any thoughts or suggestions on solving this that doesn't involve elongating the slot in the dropout?

rear-wheel-dropout.jpg

Click to expand...

I've come to the conclusion that once electrified, nobody goes back. A few light strokes with a jeweler's file on the contour and the axle will drop in further without making the dropout deeper, so no real issue IF you go back, but I'd just file it to get it centered and not worry about reverting.

Torque arms are in the top 3 "high friction points to ebikes"
Luckily theres 13yrs of info here.

amberwolf said:

Make some torque plates that bolt to the dropouts / brake mounts / etc there, that have just the double-D axle hole in them...

Click to expand...

This would work, but one thing I didn’t mention was I had to flex the frame to get the wheel to drop in without any washers, and the way the axle is designed there should be washers on both sides of the dropout on both sides of the wheel. I'm sure I could make it work using the right materials, but I have decided to use a different frame that has the room and wheel fits nicely in the dropouts. It comes with an easier challenge, working out a rear brake, which I will address below.

E-HP said:

I've come to the conclusion that once electrified, nobody goes back...

Click to expand...

I agree, I would likely never go back, but fitting it into the dropout turned out to be only one of a couple of significant challenges, so I’ve decided on a different frame, an old, non-working Pedego I had bought for parts, which is way more suited for this wheel type. The original wheel had a weird coaster brake that definitely can't be used on this wheel designed for a disc brake setup, so I will have the challenge of working out a caliper mount, but there is a decent ready-made product to solve this issue with far less fabrication than it will take to use the Santa Cruz. More to come on that modification.

michaeljay said:

Torque arms are in the top 3 "high friction points to ebikes”. Luckily theres 13yrs of info here.

Click to expand...

Yes, I’m very grateful for this site, I have browsed some of the builds and seen some awesome fabrications. I will likely pursue the Santa Cruz conversion one day when I have a lot more time, and when I do, I will go with either a geared or mid-drive motor.

Since I will not be pursuing this build because I don't want to modify the frame in any way, I am going to start a new topic on a build where I need to fabricate a brake setup on a frame that originally came with a coaster brake wheel.