dillon Posted November 7, 2015 Share So on my ride this morning, 2 spokes snapped (one the nipple broke in half), so I headed home with a wobbly wheel. when I took the wheel off to fix the spokes i found my rear axle in 3 parts. I have not been jumping crazy jumps, apart from a few little drops and log jumps. Hub has been trouble free for 2 years, the break is on the drive side, not sure my power output is strong enough to snap an axle. Any ideas why this would happen? Link to comment Share on other sites More sharing options...
ChUkKy Posted November 7, 2015 Share Hub has been trouble free for 2 years, ---- Clearly not this here BikeHub?? Im curious to know why that would break in 2 places and not 1 Link to comment Share on other sites More sharing options...
Sepia Posted November 7, 2015 Share Im curious to know why that would break in 2 places and not 1Ja, me too. Link to comment Share on other sites More sharing options...
HappyMartin Posted November 7, 2015 Share I broke three on one cycling tour. Always in the same place and never in more that one place. That's very odd Link to comment Share on other sites More sharing options...
EmptyB Posted November 7, 2015 Share Never seen that before...bizarre!! Link to comment Share on other sites More sharing options...
droo Posted November 7, 2015 Share Novatec by any chance? Link to comment Share on other sites More sharing options...
Eddy Gordo Posted November 7, 2015 Share Novatec by any chance?hmm, I would like to know that too Link to comment Share on other sites More sharing options...
dillon Posted November 7, 2015 Share Novatec by any chance?yup d812 Link to comment Share on other sites More sharing options...
dillon Posted November 7, 2015 Share all i can think of is the endcap loosened up a bit allowing the freebody some play, causing the one snap. but to snap in between the 2 bearings (which are about 1000kms old, with no play), i am stumped. About to write it of to my immensely powerful legs Link to comment Share on other sites More sharing options...
JXV Posted November 7, 2015 Share I'm betting that was caused by a jump landing or a hit on some obstacle in the trail? The shape of the axle shows a clear stress concentrator at the tapered bit. The main bearing on the drive side is far inboard to accomodate the freehub. This raises the stress on the axle in that area quite a bit more than the non drive side. The sharp taper on the inboard side of the bearing flange was not a good design choice. The second break looks to have occurred under one of the freehub bearings, not sure how that happened. I think I would replace with a more robust hub to avoid this in future. Link to comment Share on other sites More sharing options...
droo Posted November 7, 2015 Share I'm betting that was caused by a jump landing or a hit on some obstacle in the trail? The shape of the axle shows a clear stress concentrator at the tapered bit. The main bearing on the drive side is far inboard to accomodate the freehub. This raises the stress on the axle in that area quite a bit more than the non drive side. The sharp taper on the inboard side of the bearing flange was not a good design choice. The second break looks to have occurred under one of the freehub bearings, not sure how that happened. I think I would replace with a more robust hub to avoid this in future. The inner freehub bearing places a load on that point on the axle if one of the end caps comes loose and allows sideways play. It's a pretty common place for these axles to fail. Link to comment Share on other sites More sharing options...
Longbarn Killer Posted November 7, 2015 Share I always thought Novatech was one of the few Chinese products that is actually good. You have just proved me wrong. Link to comment Share on other sites More sharing options...
dillon Posted November 7, 2015 Share I always thought Novatech was one of the few Chinese products that is actually good. You have just proved me wrong. nothing wrong with the hubs, my son runs them as well, and he rides them hard, racing in the A batch. This is a perfect case of lazy maintenance. If i had put loctite on the end cap when replacing bearings, we would still be riding. Link to comment Share on other sites More sharing options...
dillon Posted November 7, 2015 Share I'm betting that was caused by a jump landing or a hit on some obstacle in the trail? The shape of the axle shows a clear stress concentrator at the tapered bit. The main bearing on the drive side is far inboard to accomodate the freehub. This raises the stress on the axle in that area quite a bit more than the non drive side. The sharp taper on the inboard side of the bearing flange was not a good design choice. The second break looks to have occurred under one of the freehub bearings, not sure how that happened. I think I would replace with a more robust hub to avoid this in future.mmmm I haven't had any jumps or rocks for some time, i am starting to think the end cap came loose, which caused the break on the freebody and I broke it again when trying to remove it . fact that I rode 25kms with it broken might also have something to do with it.... Link to comment Share on other sites More sharing options...
JXV Posted November 7, 2015 Share mmmm I haven't had any jumps or rocks for some time, i am starting to think the end cap came loose, which caused the break on the freebody and I broke it again when trying to remove it . fact that I rode 25kms with it broken might also have something to do with it....Maybe you should train less...or get a stronger hub [emoji12] Link to comment Share on other sites More sharing options...
i24 Posted November 8, 2015 Share Any ideas why this would happen? Can you post some photos of the fracture surfaces, end on or 3/4 on. It may be possible to see if ithere was a fatigue fracture or just an over stress. (A boffin with a microscope or a 10x inspection lense should be able to tell you something.) Also what is the material. Steel, stainless steel or something else? It looks a bit bright for a high carbon steel bike axle. I would guess the first break was due to an overstress, manufacturing defect or possibly missassembly. The others could be collateral damage from riding it home. The evidence of the first break might have been masked by other damage on the ride home. (But rather ride home if you can, then push 20km for the sake of science!). Link to comment Share on other sites More sharing options...
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