Mechanics and Fixing Any Questions Answered

True, true.

Anyone here using TPU tubes? I started using them about a month ago and I'm going crazy with the slow punctures. Got one in the first week, invisible to the naked eye, found it by pure luck by seeing very tiny bubbles on the first spot I happened to look at when dunking it in water. Now I've got another one in the rear, very slow - takes about 3 days to fully deflate - and fucking impossible to find. Is this normal with these tubes?? I'm inflating my rear tube every morning now, fully given up trying to repair it

Check your tyre, probably something tiny is still embeded in it.

That or there's imperfections in the tyre casing or the tyre is being run at too low psi.

Yeah and very pleased! Bought a pack of 20 for the road bike and Brompton, expecting to give a few away as party favours for a bday I then didn’t organise. Might list them here if there’s any interest, saves 140g!

I thought the general consensus was that they were pretty shit but good to carry as an emergency spare on account of the size

I’ve just rebuilt an old Kysrium rear hub on a tubular wheel set I’m planning to use for cross - it’s a pre-11 speed SL model with the SSC branding on. It’s got this rear axle which seems to have a narrow sleeve/dust seal inside that means I can’t get any standard (non Mavic) QR through it. They seem to thread into the middle but won’t pass all the way through. Am I missing something obvious, or was there some special QR to go with these?

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different tires and different tubes, first the front now the rear. I've been trying again to find it for the past 2 hours. Literally impossible, there are no visible leaks anywhere in this tube. What the fuck??

EDIT: Seems like it's not just me
https://youtu.be/VhRH3Rsz7zo?si=ZgEjF6WP806biym5

What the fuck??

Something which is a leak when stretched inside the tyre and at several bars of pressure is no longer a leak when the tube only has a couple of pounds of pressure in it and has shrunk to it's native size

That guy and Mark Zuckerberg are on opposite ends of the smiley spectrum.

More grief with this old frame that I’m already regretting bothering with. Why does the gear hanger have this weird offset (I don’t think it’s just bent?!) and is it going to prevent me ever putting a vaguely modern rear mech on it?

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Yup, meant to be like that. Vaguely Simplex / French / Puch...

Thanks. Chorus 10 speed won’t make it to the cassette even with the high limit screw all the way in.

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Take a file to it

Timesert the pedal thread?

If you are spreading the frame to fit a modern wider hub the gear hanger may need a tweak to be straight.

Problem with the rim tape and/or wheel then?

Tried dunking it in soapy water and not just try to spot the leak with naked eyes?

It’s got this rear axle

That part should have a big hole through it, if you're going to get stuck anywhere it's in the thin end, but Mavic QRs are 5mm just like any other

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How far through the hanger do the threads of the mounting bolt engage?

Not very far actually looking at it! It’s a beefy hanger. The same mech had full engagement with 2 other frames I just tried. Does this mean that, as suggested, it’s time to get the file out?

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I have an old Silca floor pump, Super Pista new in 1995. It’s worked well over the years, only replaced the gasket once. Lately though it’s been acting up and not reaching much beyond 50psi. I believe the leak is somewhere around the gauge (base mounted). I’ve never found the gauge that useful because of distance and suspected inaccuracy - would it be possible to just remove it and seal those points so that the pump still works?

EDIT - May have found the issue, I must have lost the little o ring between the barrel and the gauge. Off to the Despot with me.

Spoke head washers on a high flange track wheel: beneficial in any way?

Have a pretty loud, audible creaking going on in an old(ish, say 15+ years) bike my partner just got which I think I've now diagnosed to the hub and cassette since I:

1. don't hear creaks when not pedalling, so maybe drivetrain related
   
2. still hear creaks when standing on pedals, so probably not seat(post) related
   
3. changed out the cranks to no avail, so probably not cranks
   
4. think the cranks seem to rotate smoothly in the BB, so probably not BB
   
5. can't find cracks on the frame (though who knows?), and
   
6. seem to be able to make the creak happen by pushing on the crank at certain parts of the wheel rotation, which is why I initially thought it was a drive-side issue.
   
   

Question is, is this likely to be solved by changing the cassette, or is it the whole hub I need to change out? And are there any safety issues if she continues to ride the bike? Am worried that it turns out to be a cracked frame but am reasonably sure now that it isn't, and if the hub/cassette needs to be changed anyway I'm thinking she'd be happy to ride it until it's run into the ground.. No particularly high wattages going to be going through that drivetrain.

Checked QR skewer levers?
Do you have a spare pair of pedals you can try?

Thanks for the suggestions! Have already pulled the QRs both out, nothing seems to be out of the ordinary. Have got SKS raceblade longs on the QRs though, might this be contributing? Pulled the mudguards off the back wheel/QR to be sure and no dice though, sound persisted.

Very unlikely to be pedals, no play at all and the sound occurs at both rotations (unless it's both pedals ha).

Edit: Just pulled off rear wheel and could hardly get the cassette lockring tool in there; thought it might have been gunk and stuck something inside to get stuff out, and noticed some play between the lockring and axle. Lockring seems on pretty tight so.. freehub splines worn, maybe?

beneficial in any way?

Only if the spoke bend doesn't fit the flange thickness properly. There's nothing special about the flange diameter or intended use, the same applies to any wheel. And of course it's better to get spokes which fit properly in the first place