rear spokes on an e bike

[Tony1951]

You don't need a wheel specialist, just a bike shop worthy of the name. Clearly your local one is incompetent, so go to the next one until you find someone who is competent.

Or do it yourself, that isn't impossible since I've seen many in here learn how and succeed from online advice.

N.B. Post crossed with Saneagle's.
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Yeah I thought that a bike shop that can't fix a wheel is probably one to avoid.

 

[saneagle]

Maybe not in a 20 inch wheel, or with a very large diameter motor. I found in my 700c non-hub motor wheel there was no issue. Any gentle bending needed to persuade a spoke into position is pulled out when the spoke is tensioned.

A full build is daunting. One spoke is not!

What spoke pattern did you use? OP's bike has 2-cross. When you feed a spoke through from the outside, the spokes on the other side prevent it from being turned up to the rim. How did your around that?

 

[matthewslack]

What spoke pattern did you use? OP's bike has 2-cross. When you feed a spoke through from the outside, the spokes on the other side prevent it from being turned up to the rim. How did your around that?

If the first cross is the one just a centimetre or so from the hub flange, then mine too is a two cross pattern. I just guide the spoke as soon as it is through the rim into the most suitable gap in the opposite side's spokes, and work it gently into place. I have in this way managed spokes that pass through the flange in both 'in to out' and 'out to in' directions.

It takes care to protect the rim from the spoke end to prevent scratches, and there is a fair amount of temporary unstraightness, but I had no trouble. There was far more trouble getting the centerlock disc and cassette off without the proper tools!

Obviously my 700c on a normal hub rather than a hub motor has longer spokes and will be a bit easier, but my 26 inch old MTB wheels probably have same spoke length as a 700c hub motor wheel, and they look feasible to me.

But maybe the pattern is not as I think it is.

 

[Sturmey]

Sometimes you can keep a wheel going by a quick replacement of the broken spokes only. I have often got a pliers and bent 13g spokes into a tight circle to get around the disk. On my bike, the 32T freewheel cog was smaller than the motor hub. All my spoke breakages were at the j bend. To replace the broken spoke, I just turned the bike upside down, put a bit of tape on the nipple to prevent it from falling into the rim cavity, remove the old spoke, tread in the new spoke and dont be afraid to bend it as necessary. Do not bend close to the tread. Roughly straighten the new spoke and attach to old existing nipple (replacement spoke must be same gauge). It will have kinks but these will come out of it when you tighten up. No need to take off wheel or remove/deflate the tyre in this case. Can often be done in 15 minutes. I have also cut and make Z bend spokes, so I can always get a bike back on the road without having to order spokes or remove freewheels/cassettes.
Of course I agree that a complete rebuild is a better job as once a wheel gets into the habit of breaking spokes, it tends to continue.