Rims worn out. Worth re building anymore?

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pwa
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Re: Rims worn out. Worth re building anymore?

Postby pwa » 1 Oct 2019, 9:24pm

Just one example. There will be others.

https://www.spacycles.co.uk/m2b0s116p23 ... rizzly-CSS

Trikeyohreilly
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Re: Rims worn out. Worth re building anymore?

Postby Trikeyohreilly » 1 Oct 2019, 9:30pm

Thanks. I saw 534.5 or 535 ERD.

You gave a list of rims. Appreciated. Looks though that the only suitable is the one I have (worn out) that's not available to buy now. Damn.

If it's new spokes also I'm tempted to delay the build till I can afford new wheels.

pwa
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Re: Rims worn out. Worth re building anymore?

Postby pwa » 1 Oct 2019, 9:36pm

1mm either way will probably be okay. E.g. https://www.sjscycles.co.uk/rims-tape/3 ... rim-black/

Trikeyohreilly
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Re: Rims worn out. Worth re building anymore?

Postby Trikeyohreilly » 1 Oct 2019, 9:42pm

Ah. There are more options. Great.

I had forgotten about Hope hub flanges cracking. I had an Orange P7 some 14 years ago that when I sold (unaware) I had the buyer calling me cross about a crack "in the hub". I offered to take it back but he had already had too much work done to it to be willing to return it. I can't see any, but I'll get my LBS opinion tomorrow.

rmurphy195
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Re: Rims worn out. Worth re building anymore?

Postby rmurphy195 » 1 Oct 2019, 11:05pm

Hope hubs aren't exactly cheap or nasty, are they! Rebuild with new rims.
Brompton, Condor Heritage, creaky joints and thinning white (formerly grey) hair
""You know you're getting old when it's easier to ride a bike than to get on and off it" - quote from observant jogger !

gxaustin
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Re: Rims worn out. Worth re building anymore?

Postby gxaustin » 1 Oct 2019, 11:44pm

DT Swiss have a spoke length calculation program. Another I've used is EDD.
Recently I bought some Sapim plain gauge spokes for about £16 per wheel, inc spokes.
But it should be possible to get some similar rims, dimensionally.
I recently found that Halo White Line had the same dimensions as Mavic Open pro (700c) rims, for instance.

alexnharvey
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Re: Rims worn out. Worth re building anymore?

Postby alexnharvey » 2 Oct 2019, 7:04am

How are the spokes in the nipples when seen from the outside, under the rim tape. Are they a little below the slot or are the spokes extending beyond the nipple head? If they're much below (short) then it limits how much larger you would want to go on the ERD whereas if they're already protruding (long) you may not want to use a much smaller diameter rim.

I believe it's better they are slightly long rather than too short because of the risk of the nipple head cracking if not supported.

drossall
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Re: Rims worn out. Worth re building anymore?

Postby drossall » 2 Oct 2019, 8:09am

The odd mm may work, but if too long the threads will bottom out before enough tension is achieved, of course.

Brucey
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Re: Rims worn out. Worth re building anymore?

Postby Brucey » 2 Oct 2019, 10:16am

drossall wrote:The odd mm may work, but if too long the threads will bottom out before enough tension is achieved, of course.


A while back I did some tests to see what happens when you deliberately 'crunch' nipples down on the spoke threads, as might happen if the spokes are longer than ideal and protrude more than normal. A typical spoke/nipple combination starts to interfere when the spoke protrudes more than ~1mm to 1.5mm or so. It can be turned further with a normal spoke key, but what happens exactly?

With a brass nipple and a stainless steel spoke the result is that the spoke is (from the POV of future breakage) practically undamaged, but the nipple threads are progressively damaged.

It is normally still possible to ft a new nipple to the 'damaged' spoke and it is also possible to fit the 'damaged' nipple to another spoke, both without further damage or significant binding. In terms of weakening the connection between the spoke and the nipple, a typical 14G spoke has ~10mm of thread on it, and that thread is 56tpi. So 10mm of thread is potentially engaged by 22 turns (but probably won't be with most nipples), and each mm less than this deprives you of 2.2 turns.

I have seen many more broken nipples (from spokes being too short and the top of the nipple being unsupported) than stripped threads (through engagement being too short). Losing a few turns of engagement is undesirable but not normally such a big worry. I don't remember seeing a spoke that poked a long way through it's nipple strip the thread but this must be possible. I've seen spokes poke through nipples by at least 3mm in wheels with high spoke tension and they have been apparently reliable wheels. I wouldn't choose to do that but it doesn't seem to cause catastrophic problems with the spoke thread.

To my mind a more significant problem with spokes that poke through the nipple is often that the protruding ends can give you punctures (even with a double-walled rim); there are few rim tapes that, under tyre pressure, won't sag a little over time and this allows the spoke end to chafe through.

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~

tooley92
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Re: Rims worn out. Worth re building anymore?

Postby tooley92 » 2 Oct 2019, 2:39pm

rmurphy195 wrote:Hope hubs aren't exactly cheap or nasty, are they! Rebuild with new rims.


True, but sadly they still crack!

The loudest freehub known to man.
Remember folks 'A pessimist is just an optimist with experience!'

pwa
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Re: Rims worn out. Worth re building anymore?

Postby pwa » 2 Oct 2019, 3:42pm

tooley92 wrote:
rmurphy195 wrote:Hope hubs aren't exactly cheap or nasty, are they! Rebuild with new rims.


True, but sadly they still crack!

The loudest freehub known to man.

Is there anything that can be done to dampen the sound? Presumably the sound is partly due to a void. Is it, for example, something that can be muted by introducing extra grease?

Brucey
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Re: Rims worn out. Worth re building anymore?

Postby Brucey » 2 Oct 2019, 3:47pm

if you use a semi-fluid grease inside that makes them quieter. If the grease is too thick it interferes with pawl engagement.

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~

bgnukem
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Re: Rims worn out. Worth re building anymore?

Postby bgnukem » 2 Oct 2019, 3:52pm

Take hubs apart, check condition of the bearings, axles, freehub, and flanges and hub shells for cracks/corrosion then decide if they are worth rebuilding?

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Sweep
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Re: Rims worn out. Worth re building anymore?

Postby Sweep » 2 Oct 2019, 8:26pm

Trikeyohreilly wrote:Thanks. I saw 534.5 or 535 ERD.

You gave a list of rims. Appreciated. Looks though that the only suitable is the one I have (worn out) that's not available to buy now. Damn.

.

Set up a search alert on ebay. I recently found some mint rims of a discontinued line. Someone had had them sat in a garage for years, never got round to the planned build.
Sweep