Have a step thru commuter ebike by NCM. Called the Munich. Company that sells on line has been fantastic. Love the bike. But have had broken spokes

Rear wheel spokes on hub drive wheel have popped through flange on hub motor twice. Spokes are 13 gauge.
Bike maximum weight is 275 pounds. I'm 220. Approximately 10 pound battery mounted under rear wheel rack.
When spokes not breaking love the bike. Company has been great have now sent 2 new motor hub rims to local bike shop and have footed bill. Got 370 miles before first break, than 210 on second issue. Hoping third time lucky.
Question....if I choose to rebuild a stronger wheel......I love the bike, and the company has been terrific, even saying I could return it......,.how should it be done? Presently a 28 inch 1.5 Tire is used. The hub motor is a DAS 350 watt
Bike has fenders which obviously are not much larger than wheel width. Would flange washers work? 14 gauge spokes?
Stronger rim? Again, love the bike, and company support fantastic.
 

rich c

Well-Known Member
First, congratulations for what I think is the longest title ever. Why are you getting new rims? The LBS guy is completely lacing new rims, or just replacing the broken spokes? How qualified is that person? What brand of spokes are being used? Never heard of flange washers, but I've never built a wheel.
 
Funny start😎. Seriously, company sent new rim and hub motor twice. First repair the LBS said all looked good, tried new rim. Ran well. Then same thing happened, 2 spokes pulled through or broke from hub flange.Startedthinking I'm too heavy, but company and LBS say no. New rim sent again. Repaired today.
gut feeling is that it's going to happen again. LBS mechanic good. Spokes 13 gauge, brand unknown, probably Chinese mass production. Again, love bike, company support great, either bad luck or manufacturing screw up. Bike is sold in Europe and Australia, with no known problems like this.
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harryS

Well-Known Member
-Is it the spoke breaking at the J bend, or actually deforming the holes in the flange? I assume the latter because it would be silly to replace a motor just for two broken spokes. They do sell washers for that purpose though,

I am with Mike about Saphim Strong spokes - 13G at the elbow and necking down to 14G at the rim. It would require spoke washers at the rim because the holes were drilled for 13G, You can get better tension w/o the spokes snapping off at the elbow. If not that, get 13G spokes from a US seller.

On my first wheel build, I took the motor out of a chinese built wheel and put it in a different rim. I used Saphim spokes. There was such a visible difference in manufacturing quality, Everything just looked more sharp and well formed on the Saphim.
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-Is it the spoke breaking at the J bend, or actually deforming the holes in the flange? I assume the latter because it would be silly to replace a motor just for two broken spokes. They do sell washers for that purpose though,

I am with Mike about Saphim Strong spokes - 13G at the elbow and necking down to 14G at the rim. It would require spoke washers at the rim because the holes were drilled for 13G, You can get better tension w/o the spokes snapping off at the elbow. If not that, get 13G spokes from a US seller.

On my first wheel build, I took the motor out of a chinese built wheel and put it in a different rim. I used Saphim spokes. There was such a visible difference in manufacturing quality, Everything just looked more sharp and well formed on the Saphim.
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Seems as the spokes are pulling through the flange. I agree with all you suggest. My LBS does not carry the washers, nor the company. Since we are leaving back to Canada in a week, not possible to order and get done here. Will rebuild a new wheel there if same problem encountered. Cheers.