Hi Barchettaman,
I think it was delamination of the rim through heat buildup / manufacturing issue(?) under some heavy braking.
I'd struggled that morning to fully inflate the rear tub (stupid valve extenders) and so was running at about 90psi. Hadn't had any issues but then hit a relatively small pothole whilst travelling uphill (and hence weight over front wheel) at probably 8 mph. This was an opportunity to stop, remove tyre (so I could open the pesky valve) and fully re-inflate the tub. I saw no evidence of rim failure at that point, and given the failure was at the valve section of the rim, either I or the four people watching me change a tub would have pointed it out.
Not long afterwards we were overtaken by a tractor towing a trailer who then decided to stop just around the next corner, I hammered the anchors on and came to a stop (leaving a few skid-marks along the way…. and I'm not just talking about on the tarmac). Thankfully I missed the trailer by about 50 cm so I continued on after wishing the farmer well.
I continued on for another 3.5 hours on the ride and it was only on cleaning the bike that I discovered the rear wheel was totally gubbed.
The local bike shop I bought the bike from have been pretty decent, but their hands are tied. Unfortunately the Boardman rep has jumped to the conclusion that it was pothole damage and is unwilling to even consider a warranty claim. I've hit far bigger potholes, far harder than I did that day and caused no damage to any of my wheels. The rest of the club cycling with me that day are pretty shocked that the wheel is wrecked. I've even removed the tub from that wheel and sent pictures of the wheel showing no rim damage (other than the delimitation of the braking surface) to the rep, but so far (after >1 week of waiting) I've heard nothing. It's a real shame, I've got 4 Boardman Elite bikes and this is the first problem I've encountered… I was hoping for better customer service to be honest.
Their only suggestion was to buy a new rear from them at £350 + VAT, totalling £420 but I thought my money would be better invested in a pair of Zipp 404s… hence the upgrade.
Many thanks for your kind wishes - I'm really looking forward to Klagenfurt… a week from now hopefully I'll be ZIPPing along through the Austrian countryside with a big grin on my face :D
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