[cookie1987]

I bought a handbuilt wheelset from Spa Cycles in January 2017 (Tiagra 36h hubs, Rigida Sputnik rims).

3,300 miles later (November 2017), the rear hub flanged snapped – around a centimetre of the circumference of the flange broke off on the non-drive side, meaning that two spoke holes also disappeared.

The rear wheel was sent back to Spa Cycles who replaced the hub (with exceptional service) under warranty.

4,000 miles later (this week), my rear wheel came out of true and, upon inspection at my LBS, the new hub has 5 visible cracks running from individual spoke holes to the edge of the hub.  Two of those cracks are sufficiently large that there is a visible gap in the metal between the spoke hole and the edge of the flange – i.e. I can see through it.

My understanding is that hub failures are rare.  Does this simply sound like (very) bad luck?  Or could there be something else about the wheel which is causing this to happen?

This is on my commuter bike.  The stock wheels lasted 10,000 miles before I replaced them (worn rim; hub was still running fine).

Topic

[cookie1987]

Thanks all. I should have

Thanks all. I should have said that the failure on the new hub is on the drive side.

[fixation80]

Just to say, the non drive

Just to say, the non drive side spokes on the more traditional hubs are usually less tight, slacker, due to the dishing to accomodate the width of the gear block. This has caused problems over the years and wheel building evolved into an art form from where wheel builders gained strong reputations for reliability. Obviously the fault is due to either wheel building or hub fragility, both sides will deny responsibility. Some builders, taking into account of the increased spoke angle and less tension of the non drive side may build with brass washers at the spoke bend thus taking up any play at the point due to the slacker spokes. It may be the best advice would be to seek a wheel builder of note from cycling friends or cycling hub.  

[madcarew]

I would suggest spoke tension

I would suggest spoke tension is too high or too low (more likely the former). I’d suggest it’s a builder issue, so would suggest taking it to another bike shop for a second opinion. In the past these failures were more common, but for 2 on the same wheel from the same builder seems to point to the builder. You could take it up directly with Shimano UK. I’ve found that Shimano themselves take their customer reputation very seriously.

[Welsh boy]

The only time I have had a

The only time I have had a flange fail was about 30 years ago when (against manufacturers advice) I had a Campag hub built up radially.  To me what you have experienced is hub failure cause by too much spoke tension.  Tiaga stuff is not expensive kit and for 2 to fail from the same builder does suggest that it is something to do with the builder, I would suggest (I hate people who do what I am about to do and diagnose a problem over the internet without seeing the physical evidence themselves) that maybe the spoke tension is too high for that particular model of hub.

[CXR94Di2]

Just an observation, but

Just an observation, but there doesnt look to be much flange material around the spoke holes to give long life, or extended life. A larger circumference flange or thicker

[cookie1987]

2nd photo

2nd photo

[cookie1987]

Thanks Duncann. I wondered

Thanks Duncann. I wondered that too but it seemed unlikely given that the first failed hub and the current hub were fitted 10 months apart! Not impossible that they would be from the same batch so far apart, although the first failed hub was an older Tiagra model than the new one. 

I’ve uploaded a couple of photos. 

[Dnnnnnn]

As a man of many hubs, I’ve

As a man of many hubs, I’ve never seen failures like these. Bad batch, possibly?

[Author]

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