Mechanics and Fixing Any Questions Answered

Hmm, could be
What would the tyre options be
Much confusing

Over on Retrobike / cyclechat, Panaracer Pasela seem popular, they do a 1" version too. Very old school though.

https://www.sjscycles.co.uk/tyres/panaracer-pasela-pt-tyre-amber-wall-27-x-1-14-inch-32630/

back in the 70’s I’m sure that won’t be a clincher /hooked rim

It probably won't be, but we did have them back then.

Weinmann 27x1 1/4, probably 1970’s-era, tyres at a modest 55/60psi

Without a hook/crochet, 1970s 27×1¼" were typically rated for 45psi max. When hooked rims were introduced, they were called HP (high pressure) as the first ones allowed you to reach the dizzying heights of 60psi. The tyres would be marked with two pressures, one for normal rims and one for hooked.

Ah, now, this might be the thing
Having been ‘conditioned’ to running all the things at c. +90 then I might need to step back from the JoeBlow
Thanks all, will try running a squisher set up - worrying given I’m heavier than a pallet of block paving now :(

Very old school though

Rotrax they’re attached to is 1953, so yes

I have a full suspension steel Marino mtb. I noticed that the powdercoat cracked next to the weld on the main triangle of the frame. Should i be worried??

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This looks pretty suspect. Take off more paint around the join with a pen knife or emery cloth so you can inspect the tube properly. If it’s not cracked hammerite/nail varnish over the stripped area.

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Looks goosed tbh

🤔

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Thanks, thats a good idea

🤔

I think he meant the OP's goose is cooked

Bought a Tune seatpost clamp to replace the stock one on my Condor, and foolishly didn't review the stack height. The Tune clamp is taller than the old clamp, and sits c.3mm above the top of the seattube/seatclamp section of the frame (rudimentary annotations below).

Is this going to damage the frame at all/not function as a seatpost collar?

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not function as a seatpost collar?

That design doesn't function properly regardless of which frame you attach it to

Are the clamps with the rotating whatsit better?

Burst open on the way home last night (thankfully just up the road from the homr). Lesson learned! Thankfully already have a spare to swap on.

Are the clamps with the rotating whatsit better?

Yes, ideally rotating whatsit both ends

Noted, I'll have a look at some alternatives, cheers.

In the meantime, is the current setup likely to fail as a result of the height difference?

is the current setup likely to fail as a result of the height difference?

The theoretical issue is that the clamp will walk up the seat tube and eventually let the post slip. That's probably going to more annoying than dangerous, and it's going to put a big ugly score up the most visible part.

rotating whatsit

Those are nice, but I'd argue non essential, especially if all the tolerances are nice enough that it clamps with minimal flex.

That 3mm lip sure is weird, though... I'd expect a minimalist part, from that brand in particular, not to have such obviously wasted metal on it. Maybe it's a dud unit? I'd be tempted to dremel 2mm of that lip out - and by going a hair deeper to ensure fit, that would leave the upper 2mm of the tube less, or not, clamped which would prevent it walking off.

Interesting. Out of curiosity, what would cause it to walk up? It not being seated properly? There's no upward pressure on the clamp so I'm struggling to understand the mechanics at play. In any case, it sounds like I can keep an eye on it for now - I'll scour the internet for a chrome clamp of the correct height/fastening mechanism.

@Kimmo I'm not sure to be honest. The Barachhi frameset has a designated portion of the seat-tube that's good for clamping, ie. it's of a narrower diameter and is raw carbon, rather than painted. I think this is my fuck-up, not Tune's - I should've got the right height collar. Not sure I quite follow with the dremel instructions though, do you mean dremel the bottom of the clamp to make sure it sits flush (ish)?

Out of curiosity, what would cause it to walk up?

It squishes the top of the seattube so that's a smaller diameter and the clamp will slide up towards that smaller diameter.

Tester will put it in more technical language.

Oh I see, so it's about uneven force applied to the clamping area, with more pressure applied to the top of the clamping area. Is this still the case if the top of the clamping area sits above the bolt on the seatpost collar?

Green whatsit chainrings off ebay? Does anyone do an aftermarket sub-compact spider for them?

Yeah I think the seatclamp as we know it is pretty poorly engineered. Like, it works fine, but from an absolute engineering pov it’s a bit shit.

I managed to deform a Weinmann non-hooked rim beyond repair when a tyre blew off the rim as I was pumping it (Gatorskin?) wayyyyy over-pressure to try to get it to seat. It's possibly the loudest thing I've heard.

I replaced them with a set of hooked rims, which are much more reassuring. FWIW, I also run Paselas, which I like as an all-round relaxed road/touring tyre. Fawkes cycles have a good range of sizes.

Incidentally, you're not trying to fit a folding tyre to straight-sided rims are you?