Any question answered...

Any spacers on the freehub before the cassette?

Yup, a small one. The one you fit to a 10-speed setup. Cassette feels tight, there's no side-to-side movement.

What happens should a lockring break? Nothing catastrophic, right? Just lack of drive?

Basically I can't say for sure how many threads are engaged.

I've taken it for a couple of mile-long spins and it seems OK but now I've got The Fear.

2 threads is not enough, this has been the problem with 10spd free hubs and 11spd cassettes.

Sounds like you may have to replace the freehub before returning wheels to their owner if the threads are stripped.

Having lost one sprocket you will now need to reset your limit stops.

I've reset the limits. Will buy new freehub. But will I die if I ride this as-is in the Pyrenees? That's the immediate concern, as I leave in a couple of days. Is there anywhere I could buy a decent replacement rear wheel that I could pop this cassette on? Could also serve as sorry-I-cocked-up-your-freehub replacement? Hub is Miche B0713. 32 hole. Black.

You should be fine. Is there a new equivalent wheel that has an 11spd freehub?

Not sure of quality of these. Can't find anything matching that model number on Google.

Maybe these?

http://www.wiggle.co.uk/miche-race-707-clincher-road-bike-wheelset/

Anyone know where I can pick up a Shimano R500 rear tomorrow?

Right. Just bought Shimano RS11 rear, should be in local Evans Tuesday. That'll sort the problem properly and sort owner out. I'm a muppet.

Thanks all.

:)

What's the name if that guy that does those mad loopy sampled videos where giant hands pick people up etc?

Cyriak?
https://www.youtube.com/user/cyriak

There's probably faster wheels than the Shimanos for the money.
Like what? Genuine question.

How much are we talking? Scirocco 35 are about 170 on wiggle I think.

Imma get the wheels. Mamil in training.

Anyone know where I can pick up a Shimano R500 rear tomorrow?

You're welcome.

Really, the answer is to work 72 hour weeks and buy both.

No, the correct answer is work less and ride more!

Anyone got an unwanted rear derailleur? Any old piece of junk will do. Just want the mounting bolt so I can see If I can DIY an alignment tool.

^ A trashed Golden Arrow?

Tyre sidewall splits... how likely are they to explode?

IE, should I replace this quick sharp?

Front wheel, exchange immediatly - back wheel, living on a prayer.

^^Very.

Immediately!

It's a back wheel, thanks guys, will chuck it ASAP.

It's not had a huge amount of use and never been pumped up above the limit, should I be irritated that it's split so soon?

If those are scratches on the rim from a kerb, probably not..... Even if not, you'll never get your money back so just buy better/different tyres.

Don't think there's any scratches, I'll check. But yeah, I was just wondering whether to swap brands, I've previously had good luck with these (Vittoria Randos) so think I'll give them another chance.

How much are we talking? Scirocco 35 are about 170 on wiggle I think.
About 7/800 retail. No zipps.

You're welcome.

I already have R500s, smarty pants.

Anyone know where I can pick up a Shimano R500 rear tomorrow?

I have a pair of R501s you could buy for £40, based in east London.