Trouble removing rear wheel - Biktrix stunner LT

Zarda

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May 13, 2021
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Bike: Biktrix Stunner LT (rear hub motor)
Issue: Cannot seem to get the rear tire off to change a flat.

So hubby had a run in with a nail, and we have to change the rear tire. Seems like a simple thing. Followed several videos. No matter what we do, can't seem to get that thing to budge at all. Neither of us are very mechanical, but we both have removed tires off standard bikes.

- unplugged the power to the hub
- loosened the bolts on both sides of the axle
- you'd think you should just have to pull back the Derailleur, and pop it out...but no. and no matter how much force there is no movement on either side.

Photos:
Can anyone see anything we might be missing? Any help would be appreciated.

side view-1.jpg
top view break side.jpg
Top-view 1.jpg
 
I have similar problem that was easy to deal with where I just have to separate the clamping force of the dropouts, I just shove in the handle of a long adj wrench to separate each side of the dropout, then deal with the chain while sliding the wheel out. Thing is I have a large diameter direct drive hub motor making it easy for me to do that, you have a small geared motor which doesnt extend much beyond the fw/cassette.

Another thing to note is maybe the motors axle twisted a bit and is getting hung up on one side where it made a groove in the dropout. Take same adj wrench to axle flats and rotate axle back and forth a few times. I do that sometimes to seat the axle deep into the dropout slot.

In your case with the smaller hub diameter motor, your just going to have to man handle each side of the dropout. You'll have to release that friction, so pull the dropout out, and let it retreat back to normal resting position. Probably best to have the bike laying on its side, stand over it with your feet to the side not on the wheel and pull up. Take the bolts off completely off the axle so the bolts dont interfere, the one cable side just spin that out to the cable.

Be sure your forcing the wheel out in the same direction as the dropout slot.
 
It looks from the pictures like the chain is jammed up in there crazy, and the derailleur hanger (the silvery aluminum piece between the frame and the derailleur) is bent inwards.

It will be a lot easier if you go ahead and take off the derailleur guard (the black thing held on with two little bolts), take the nut all the way off the axle and slide it up the wire, and take the derailleur off the hanger (it can stay around the chain, with the cable still hooked up, just detached by unscrewing the 5mm pivot bolt, then hanging there). All of that stuff makes it hard to see what's catching, esp putting the wheel back in. You might have to spin the wheel backwards as you're pulling on the lower part of the chain to get it unjammed.

As Markz wrote, the steel axle can dig into the softer aluminum frame, and needs to have the axle rocked back and forth in the dropouts to break loose.
It's usually 10mm flats on the axle.

You'll probably need to go to an actual bike shop that has the alignment tool to straighten out the derailleur hanger after reassembly, or the derailleur can get caught in the spokes when you shift to lower gears, which can break a lot of stuff really fast.

Fyi, don't try to straighten the hanger without the derailleur mounted to it, it's tempting as you can just slide a wrench on there and bend it out, but it makes the hole for the pivot bolt go oval, and then you can't screw the derailleur back in.
 
ignore the chain, I moved it for a min to get my phone in to take the shot. It was just resting in place. Was put back on / cleaned / lubed afterwords.

Ended up just taking it in to the shop. Read a lot of others having the same issue getting that wheel off the 1st time. Both hubby & I suffer chronic back pain, very arthritic hands. We can do basic maintenance, but this was getting to be a bit hard on the hands. Once it's done this first time, we should be good to go.

Thanks much for the tips.
 
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