# Novatec hub assplode



## deviousalex (Aug 18, 2010)

Some friends and I were heading down a descent at around 35 mph. Suddenly I hear a "tink" sound then my handling goes all wobbly. I stop and find out part of the front hub flange broke off and a spoke came loose and flew everywhere. Since this was a 20 spoke wheel it went extremely untrue and started rubbing off the carbon on the inside of my fork. It also left a few scratches on the outside of the frame and almost sheared my front derailleur cable in half. Has anyone else had this happen or know of this being a common issue with Novatec hubs? I'm sure I can get the hub warrantied but I don't think I'll use Novatec again if this is a common issue. The hub in question is an A291SB.

Will the spokes be useable?

How about the nipples?

Will the rim be useable? When I span it after I let all the tension out of each spoke I saw it was still extremely untrue and had a hop vertically in it.


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## bobonker (Feb 12, 2011)

How much tension was on the spokes? Radial lacing puts a lot of stress on the hub flange. 

Bob


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## deviousalex (Aug 18, 2010)

I'm not sure but the wheel was built by a professional wheel builder.


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## November Dave (Dec 7, 2011)

If my experience is any indication, it's exceedingly rare. I'd guess I've built about as many wheels with those hubs as anyone, and ridden a bunch of miles on them, and they never give a peep of trouble. I'm guessing the hub shown isn't one I built since I'd have gotten an email about. 

We build fronts within the range of about 95 to 110 kpf, radial and 2x lacing (radial wheels get a bit more spoke tension than 2x).


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## Kerry Irons (Feb 25, 2002)

deviousalex said:


> Some friends and I were heading down a descent at around 35 mph. Suddenly I hear a "tink" sound then my handling goes all wobbly. I stop and find out part of the front hub flange broke off and a spoke came loose and flew everywhere. Since this was a 20 spoke wheel it went extremely untrue and started rubbing off the carbon on the inside of my fork. It also left a few scratches on the outside of the frame and almost sheared my front derailleur cable in half. Has anyone else had this happen or know of this being a common issue with Novatec hubs? I'm sure I can get the hub warrantied but I don't think I'll use Novatec again if this is a common issue. The hub in question is an A291SB.
> 
> Will the spokes be useable?
> 
> ...


Ah, the beauties of low spoke counts and radial spoke patterns. Neither adds anything significant to wheel performance but "when good wheels go bad" the consequences are clear.


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## deviousalex (Aug 18, 2010)

Kerry Irons said:


> Ah, the beauties of low spoke counts and radial spoke patterns. Neither adds anything significant to wheel performance but "when good wheels go bad" the consequences are clear.


Don't worry, my race tubular has even less spokes, 16


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## SystemShock (Jun 14, 2008)

Kerry Irons said:


> Ah, the beauties of low spoke counts and radial spoke patterns. Neither adds anything significant to wheel performance but "when good wheels go bad" the consequences are clear.


Sums it up.


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## Randy99CL (Mar 27, 2013)

Sram, for one, voids the warranty on hubs that are radially laced.


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## the mayor (Jul 8, 2004)

"I'm not sure but the wheel was built by a professional wheel builder. "

That doesn't mean he didn't over tension it.
BUT....any hub can fail even when the wheel is built right.
I had a King hub that was laced 3x that broke just like the picture.
Stuff breaks. There are a billion of these hubs out there....how many do you see on here failing?


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## rruff (Feb 28, 2006)

deviousalex said:


> The hub in question is an A291SB.


That is a very light 60g hub. Novatech doesn't state the shell material, but IMO the higher strength alloys like 7075 are a poor choice here. Something like 6061 is better because of its resistance to stress corrosion cracking. 

Do you live or ride in a coastal environment, or ride on salted roads?

The spokes can probably be reused, and the nipples if they were well lubricated. If the rim isn't straight, it's dead.


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## markrhino (Nov 28, 2011)

Had the same thing happen to me on a front Novatec hub just the other day. Laced radially (20H) to 80Kgf, Sapim laser spokes and Velocity A23 rims. Definitely learnt my lesson here. No more cheap hubs or radially lacing.


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## bobonker (Feb 12, 2011)

rruff said:


> That is a very light 60g hub. Novatech doesn't state the shell material, but IMO the higher strength alloys like 7075 are a poor choice here. Something like 6061 is better because of its resistance to stress corrosion cracking.


Actually, that looks like the standard "heavy " A291SB that weighs 76g. The A291SB-SL is the 60g version. It's thinner through the middle and has additional holes drilled into the flange area. I haven't used the SL hub and don't plan to either!

A291SB-SL (Thanks, bdopcycling.com):









Bob


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## SystemShock (Jun 14, 2008)

bobonker said:


> Actually, that looks like the standard "heavy " A291SB that weighs 76g. The A291SB-SL is the 60g version. It's thinner through the middle and has additional holes drilled into the flange area.
> 
> I haven't used the SL hub and don't plan to either!
> 
> ...



I guess SL not only stands for 'super light', but also 'stupid light' as well. Bummer.


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## deviousalex (Aug 18, 2010)

rruff said:


> Do you live or ride in a coastal environment, or ride on salted roads?


I live in the SF bay area and ride the coastal highway a fair amount.


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