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Discussion Starter · #1 ·
Depending on how you look at it I was either very lucky or very unlucky. I had just finished decending 6500 ft and was braking to a stop at my vehicle when I heard a cracking sound and my front wheel skidded to a stop. I had almost stopped when it happened so I didn't go down. My front wheel was badly out of true and rubbing on the brake pads. The hub flange had cracked off expelling three spokes! The 20 hole m5 hub was laced to an edge 25 carbon rim. When i got home I carefully loosened all the remaining spokes a little at a time around the rim until I had removed all the spokes. Can I reuse the spokes and rim? It's hard to tell but the spokes seem fine and the rim lays on a flat table with maybe a 1mm gap on one side of the rim.( the table may not be that flat)

I am new to building wheels and would probably have my local shop lace them up with a new hub if that is possible. Since I want to reuse the spokes the new hub must have a similar dimension to the broken M5 hub. I have measured the m5 hub and come up with these measurements. Hub flange diameter 30mm and outside of flange to outside of flange 75 mm or hub center to outside of flange 37.5 mm

Extralight ultrafront sx hub has the following dimensions : flange diameter 29mm center to flange 38mm. Do you think this hub would be a drop in replacement for the m5? Fairwheel bikes is out of stock on the hub does anyone know another US retailer of these hubs?

Am I silly to want to reuse the rim and spokes? the rim and spokes have less than 100 km and are almost brand new.

Disappointed to have broken my wheel but so happy it didn't happen while i was doing 40 mph getting ready to enter a tight curve.
 

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Depending on how you look at it I was either very lucky or very unlucky. I had just finished decending 6500 ft and was braking to a stop at my vehicle when I heard a cracking sound and my front wheel skidded to a stop. I had almost stopped when it happened so I didn't go down. My front wheel was badly out of true and rubbing on the brake pads. The hub flange had cracked off expelling three spokes! The 20 hole m5 hub was laced to an edge 25 carbon rim. When i got home I carefully loosened all the remaining spokes a little at a time around the rim until I had removed all the spokes. Can I reuse the spokes and rim? It's hard to tell but the spokes seem fine and the rim lays on a flat table with maybe a 1mm gap on one side of the rim.( the table may not be that flat)

I am new to building wheels and would probably have my local shop lace them up with a new hub if that is possible. Since I want to reuse the spokes the new hub must have a similar dimension to the broken M5 hub. I have measured the m5 hub and come up with these measurements. Hub flange diameter 30mm and outside of flange to outside of flange 75 mm or hub center to outside of flange 37.5 mm

Extralight ultrafront sx hub has the following dimensions : flange diameter 29mm center to flange 38mm. Do you think this hub would be a drop in replacement for the m5? Fairwheel bikes is out of stock on the hub does anyone know another US retailer of these hubs?

Am I silly to want to reuse the rim and spokes? the rim and spokes have less than 100 km and are almost brand new.

Disappointed to have broken my wheel but so happy it didn't happen while i was doing 40 mph getting ready to enter a tight curve.
Some will tell you to not reuse spokes, but I do it all the time. In several hundred thousand miles of riding I've only suffered one hub failure but lots of rims have come and gone and I've frequently reused the spokes to build a new wheel. My current back wheel is on it's 3rd rim with the same spokes (85,000 miles total on the hub and spokes). You didn't say how many miles you have on your wheel but it sounds perfectly reasonable to reuse the rim and spokes. Whether a bike shop would be willing to install used spokes is a discussion you'll have to have with them.
 

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Cranky Old Bastard
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Yes, what Kerry said.

I bet that your wheel was radially laced.

Make sure that your new hub is certified for radial lacing; some companies don't support it.
For example, Sram warns you (on some models) that the warranty is void if they are radially laced.
 

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Discussion Starter · #4 ·
yes it was radially laced with 20 spokes. I am unsure I will find any hub with a flange size small enough to reuse the spokes. I had measured the flange size incorrectly previously. the distance from center of spoke hole to center of opposite spoke hole is only 22mm on the m5 hub!
 

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Discussion Starter · #6 ·
the rim is 1 mm out of true laying on a reasonably flat table. the spokes never got bent I was braking at about 5 mph when the flange snapped off the hub realeasing the three spokes.
 
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