Author Topic: Tell me about: spokes / spoke count.  (Read 1297 times)

Tell me about: spokes / spoke count.
« on: January 29, 2020, 11:43:37 am »
I had Spa Cycles build me a Surly LHT for touring 4 years ago. It came with some Spa built Exal LX17 rims, Deore hubs, spokes: 32/36. They have been bombproof.

I seldom do heavily packed tours anymore, and found I was using the bike rarely so I whacked on some 42mm gravel tyres to make it more of a mixed terrain commuter/fun machine. I've fallen in love with the bike again, so that's all good.

Anyway, i've been suffering with p*nctures, mainly thorns. It's the only bike in my fleet that's not tubeless so that bugs me. Also, riding off road is accelerating the wear on the braking surfaces. Rim brake / tubeless options seem to be few and far between, especially anywhere near the spoke count i'm looking to replace.

My question is - Is 32+ spokes complete overkill? It's a heavy bike (15kg) with a 80kg rider with occasional commuter/overnight luggage. Would 24/28 be alright on the more 'sporting' terrain? I really don't know where to start.

Peat

Re: Tell me about: spokes / spoke count.
« Reply #1 on: January 29, 2020, 11:47:58 am »
Why do you want to reduce the number of spokes?  Spokes really don't weigh much at all, and with fewer spokes you often neeed a heavier rim to compensate so as a weight saving measure forget it. Will it affect your average speed, nope. I suppose the real question is, if a spoke breaks on your wheel, is it no biggie you'll just walk home / get picked up, or would it be a bigger issue?  A spoke breaking on a 36 spoke wheel wouldn't impact your ride you'd just keep riding, but on a 24 / 28 wheel it likely to put the wheel quite a bit out of true.
If you don’t make time for exercise now, sooner or later you’ll need to make time for ill health.

bludger

  • Randonneur and bargain hunter
Re: Tell me about: spokes / spoke count.
« Reply #2 on: January 29, 2020, 11:49:52 am »
Assuming you are talking about 700c wheels here. I'm not a genius bike fettler but here's my experience with spokes - I have Mavic Allroads ( https://yacf.co.uk/forum/index.php?topic=112882.0 ) which are 24 front and rear. I weigh in around 93 kg, my bike is about 11 and I can carry anything between 10 and 15 kg of stuff when I'm out on the bike. Both wheels run beautifully straight after 5 months of use which has included cyclocross, audax, touring, and a bunch of other silly things. Yes it's true that a broken spoke would be more of a fiddle to get tolerably true but then with disc brakes that's less of a big deal, and newer 'straight pull' spokes are dead easy to fit when out on the road without any need to remove cassettes or whatever. My multi tool comes with a spoke key so if I were riding around the world I could tape a few spare spokes to the frame and put them on if necessary.

I get the feeling that cyclists' conservatism is at play here. I expect if you went back in time a few years ago the old sweats would be warning everyone that a spoke count below 42 would be asking for trouble.

I am mooting getting new wheels going forward, made with tougher rims, and maybe with a dynamo, and I won't be worried about spoke counts very much.
YACF touring/audax bargain basement:
https://bit.ly/2Xg8pRD


Re: Tell me about: spokes / spoke count.
« Reply #3 on: January 29, 2020, 11:52:31 am »
Compared to some wheel sets available, 24/28 could be considered a conservative choice.

I’ve had no trouble with 24 spoke wheels. Try it and see.

Re: Tell me about: spokes / spoke count.
« Reply #4 on: January 29, 2020, 11:53:27 am »
Why do you want to reduce the number of spokes?

I don't particually. Off the shelf wheelsets (that tick the rim brake / tubeless boxes) just don't seem to come in higher spoke counts.

quixoticgeek

  • Mostly Harmless
Re: Tell me about: spokes / spoke count.
« Reply #5 on: January 29, 2020, 12:27:49 pm »
I get the feeling that cyclists' conservatism is at play here. I expect if you went back in time a few years ago the old sweats would be warning everyone that a spoke count below 42 would be asking for trouble.

Part of it is that materials science has come on a long way in the last few decades. This means that you can get away with a lot fewer spokes.

J

--
Beer, bikes, and backpacking
http://b.42q.eu/

bludger

  • Randonneur and bargain hunter
Re: Tell me about: spokes / spoke count.
« Reply #6 on: January 29, 2020, 12:36:36 pm »
Exactly. Though I have to admit I am a bit jealous of how old steel rims could be bent back into shape and rode on for a few days as this one allegedly was...

YACF touring/audax bargain basement:
https://bit.ly/2Xg8pRD


Re: Tell me about: spokes / spoke count.
« Reply #7 on: January 29, 2020, 02:46:17 pm »
Clean and lube your existing hubs and then rebuild with Kinlin XR22T and RT. Asymmetric rear in 36 holes from spa and 32 hole front. Brilliant tubeless rims. You may need new spikes - I can’t remember the end of the lx17.


Re: Tell me about: spokes / spoke count.
« Reply #8 on: January 29, 2020, 02:47:14 pm »
Or if you do want few spokes, think about 24/28 on Kinlin 31T. Much deeper and very stiff rim.

Re: Tell me about: spokes / spoke count.
« Reply #9 on: January 29, 2020, 02:59:44 pm »
Clean and lube your existing hubs and then rebuild with Kinlin XR22T and RT. Asymmetric rear in 36 holes from spa and 32 hole front. Brilliant tubeless rims. You may need new spikes - I can’t remember the end of the lx17.

you will do, the ERDs are not even close.

If you are getting lots of rim wear and you are carrying on with rim brakes then I would think twice before getting 'modern' rims just because they are tubeless compatible; they mostly have very thin braking surfaces and will wear out in about 1/3 or 1/4 of the mileage of a sputnik.

Some other options might include

- running tubes with sealant
- using those tyres sold by Giant which are 'tubeless with a built-in tube' if you like
- using tougher tyres
- converting to hub brakes and tubeless rims (that don't have to wear out)
- fitting one hub brake so the rim brakes get an easier time of it.

On the latter point sturmey X-RDC hub fits 8/9/10/(11sMTB) cassettes and could spare your rims the worst of it.

The 32/36 wheelset you have ought to need nothing other than new rims when they wear out, for two or three sets of rims at least. With fewer spokes, not so much; wheels with fewer spokes in are also (in many cases) just too flexible for any kind of hard use, which you may notice more with rim brakes than with disc or hub brakes of course.  Four DB spokes weigh ~30g and reduce the fatigue loadings on the spokes by about 15% or so, and likewise increase the stiffness of the wheel.   

It is currently fashionable to have not very many spokes in wheels.

 Fashion is basically pretty stupid.

cheers

Re: Tell me about: spokes / spoke count.
« Reply #10 on: January 29, 2020, 03:11:29 pm »
That depends.

The best riding wheels I have owned have always been low- ish count high tension wide-spoked factory wheels, like Kysrium SL or Campag Shamal.

Yes, they have some disadvantages, such as becoming unrideable if a spoke snaps, and the added difficulty of the repair. But...none of those are anything to do with the actual ride, which is phenomenal and which hand built wheels cannot match.

Sorry.

Re: Tell me about: spokes / spoke count.
« Reply #11 on: January 29, 2020, 04:43:50 pm »
Cant go wrong with the spa 36 spoke variations .. I have them on my single speed with rims, my road bike with disks and my touring bike and have had a few pairs on other bikes since i discovered them in 2014.... I used to be a heavy rider so they were invaluable... now im several stone lighter but for £2-300 a pair I see no reason to move away.

Karla

  • car(e) free
    • Lost Byway - around the world by bike
Re: Tell me about: spokes / spoke count.
« Reply #12 on: January 29, 2020, 06:16:03 pm »
20,000+ miles of loaded touring on a pair of 32 spokers and the rear was a few mm out.  Suits me.

(My 12 spoke carbon Corima is still going strong too.)

Re: Tell me about: spokes / spoke count.
« Reply #13 on: January 29, 2020, 07:18:44 pm »
Exactly. Though I have to admit I am a bit jealous of how old steel rims could be bent back into shape and rode on for a few days as this one allegedly was...



Is it just my bad eyesight or is that really a Weinman alloy rim such as what we all rode BITD if we were lucky enough? Doesn't appear to be chrome steel but yes they could be bent back (although straightened might be a bit ambitious as a term). The first wheel I learnt to build on was one of these, recovered from my sister's bike after my dad drove into it in the garage, and it really was very nearly as bent as that one (although my efforts owed more to the optimism of adolescence than to skill and critical quality control).

bludger

  • Randonneur and bargain hunter
Re: Tell me about: spokes / spoke count.
« Reply #14 on: January 29, 2020, 07:20:40 pm »
It's from the rough stuff fellowship book, I assume it is steel since it says it was bent back and ridden on.
YACF touring/audax bargain basement:
https://bit.ly/2Xg8pRD


Re: Tell me about: spokes / spoke count.
« Reply #15 on: January 29, 2020, 07:31:18 pm »
Personally I'd try a tubeless conversion on your existing rims, given that you intend to use high volume tyres it should have a good outcome.
Most of the stuff I say is true because I saw it in a dream and I don't have the presence of mind to make up lies when I'm asleep.   Bryan Andreas

Re: Tell me about: spokes / spoke count.
« Reply #16 on: January 29, 2020, 07:38:43 pm »
It's from the rough stuff fellowship book, I assume it is steel since it says it was bent back and ridden on.
I've seen a wheel almost that bad brought back to life enough to finish the ride, and still have usable canti brakes, by simply whacking it on the ground.  I had a go next time I had a knackered wheel and it's surprising how little force is required, though it's frustrating to get it right.  Plenty of youtube demos.

Re: Tell me about: spokes / spoke count.
« Reply #17 on: January 29, 2020, 07:39:47 pm »
It's from the rough stuff fellowship book, I assume it is steel since it says it was bent back and ridden on.

I think a chromed steel rim would be much harder to straighten than one of those alloy ones (my memory is that they were quite soft, pringled quite easily and were not anything as like as rigid as a modern box rim). That one doesn't need to straighten modern rims as often may be an advantage to some just as being able to repair extreme warps might be an advantage to others - back to the advances of modern material science. Could the ultimate touring rim be carbon with a heavy lay on a disc braked bike (if such a thing exists)?

bludger

  • Randonneur and bargain hunter
Re: Tell me about: spokes / spoke count.
« Reply #18 on: January 29, 2020, 07:44:12 pm »
I thought that an alloy wheel if 'bent back' from a 'taco' that severe would be basically kaput from faitgue 🤔
YACF touring/audax bargain basement:
https://bit.ly/2Xg8pRD


LittleWheelsandBig

  • Whimsy Rider
Re: Tell me about: spokes / spoke count.
« Reply #19 on: January 29, 2020, 08:19:36 pm »
Nope. Those channel-section Al rims were soft as butter and I’ve (carefully) stepped on more than one pringled wheel to straighten them and continue riding. If the pinned joint got too distorted, the rim was toast but otherwise they were remarkably forgiving. Thick sections with low yield are like that. It is the high-strength, thin-walled stuff that is sensitive to fatigue, cracking, etc.
Wheel meet again, don't know where, don't know when...

Re: Tell me about: spokes / spoke count.
« Reply #20 on: January 30, 2020, 08:55:44 am »
Personally I'd try a tubeless conversion on your existing rims, given that you intend to use high volume tyres it should have a good outcome.

Thought about it, i've done it on the MTB to good results but would feel a bit nervous about doing it with double the tyre pressure (25psi/50psi).

I think Brucys' suggestion of sticking a bit of sealant in the tubes is the most cost effective solution for now, i'm hardly going to notice the extra grams. When these rims are worn out, i'll probably give Spa another call.

Cheers for the input, all.

Karla

  • car(e) free
    • Lost Byway - around the world by bike
Re: Tell me about: spokes / spoke count.
« Reply #21 on: January 30, 2020, 09:35:06 am »
When these rims are worn out, i'll probably give Spa another call.
Please don't do that to yourself.  Riding around on tractor wheels is a mild form of self harm.

S2L

Re: Tell me about: spokes / spoke count.
« Reply #22 on: January 30, 2020, 09:54:18 am »
The front wheel doesn't really matter in a rim braked bike, so 20 or 24 light spokes (Sapim laser or DT revs) are generally OK.
The rear is trickier and I tend to build 32 spokes for anything where reliability is a requirement.
The difference between 28 and 32 is generally 30-40 grams.
I would rather build 32 with Sapim D-light (an excellent compromise) than 24 with Sapim Race... the overall mass of the wheel will be similar.

In a disc braked bike you need both front and rear to be load bearing, so basically you think in terms of building "two rear wheels"

Re: Tell me about: spokes / spoke count.
« Reply #23 on: January 30, 2020, 01:32:37 pm »

Is it just my bad eyesight or is that really a Weinman alloy rim such as what we all rode BITD if we were lucky enough?.....

I would say that it is. Either that or a Birmalux, (which the weinmann was a copy of). Those rims had a welded joint and were indeed rather soft.  Single walled rims lack torsional stiffness/strength, so can 'recover' from a  dramatic fold-up like that (although they are more likely to suffer one too, of course).

Roadside repairs of any kind that allow the bike to be ridden are 'good enough' to get you home but usually the spoke tensions are all over  the place. If you remove a rim like that from the wheel completely, often it can be rendered straight again, using devious bending. Once reinstalled the wheel is likely to be just fine, provided you have not left any sudden kinks in the rim.

The strain in a single wall rim to change its shape isn't very great, and provided the material is soft and ductile, you won't hurt it. However many modern rims are made differently eg

- twin walled
- alloy that work hardens very quickly
- heat treated alloy (for more strength but less ductility)
- (unevenly) machined braking surfaces


all of which make you chances of straightening a bent rim somewhat less.

FWIW is you have a deep section rim and not many spokes, it is possible to make a wheel with adequate  radial stiffness. However even if the rim is pretty stiff, the wheel is unlikely to be particularly stiff laterally.  When you are giving it full gas up hills and in sprints (which not everyone does for sure), this lack of stiffness is likely to be costing you, even if the brakes don't actually start rubbing (which they often  do).   A simple test is to see how easy it is to push the rim onto the brake block using your fingers.  Obviously this isn't exactly the same as when riding but it is fairly close. Very many modern wheels fail this simple test, because they are basically a load of flexy nonsense.  They 'feel wonderful'?  Emperor's new wheels...?

cheers

Re: Tell me about: spokes / spoke count.
« Reply #24 on: February 01, 2020, 09:34:39 am »
If you want less spoke weight, use thinner spokes rather than fewer.  DT Revs are a pain to build with but are very good for a front wheel or the LH side of a rear wheel.  The wheel is just as strong but you save the same sort of weight as if you'd lost 4 spokes.
Never tell me the odds.