294 wheel update:
Good progress this weekend. True to their word, my local tyre place were happy to split the tyres from the rims - total cost £3.60 (10 doughnuts, 10 cookies).
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Then attacked the bolts (they were soaked in WD40 overnight). The front wheels were both torqued significantly higher than the rears - to the point where I had to apply enough force where each one felt like it was near to breaking. I got all but one bolt off the first wheel, then I think I got impatient with the last bolt and pushed it too hard too quickly and the bugger snapped

. 55 out of 56 out successfully though, not too bad. Took about 1.5 hours. My IT worker hands are feeling it today
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Also, further to my post earlier - as far as I can tell the bolts themselves are M7 shank, but a M8 splice socket is needed to remove. They are 32mm long including the tip, which I think makes them the same as the common titanium BBS bolts you see available. I've bought a set of 10 replacements from Ebay to replace the single one I snapped, plus any more which may go when I re-assemble. Hopefully they'll be the same, size and thread wise, will report back and post all the sizes up for future reference.
The snapped bolt is beyond my pathetic DIY skills, especially considering it's titanium - so my engineering friend is going to have a crack at it (though he thinks he has all 'easy out' sizes EXCEPT M7). I've not overly concerned if I end up with one bolt having to be glued on for show, I can't imagine having only 13 bolts present on one wheel represents much of a safety issue.
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I was working on each alloy sitting on top of 3 tyres - this makes them a perfect chest height to be able to apply my [considerable!] body weight to get the bolts out, plus the rubber base just about stopped the wheels from spinning around. On each wheel, the 'face' was well and truly stuck to the round part and needed some decent persuasion with a mallet - one of the spare tyres was also useful for this purpose (the one on the mat) as there is enough room to balance the wheel on top of the tyre, but giving the face enough room to fall through having been suitably whacked.
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And the finished result - will await feedback from bolt extracting friend before ploughing on. Gave all the bolts a scrub today but they didn't really need it to be fair, they're in remarkable condition for a decade old.
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