Workshop tales, trials and disasters.
Maintenance tips, techniques and myths.
Technical discussion, description and outright lies
20 posts • Page 1 of 1
For my 25 inch frame Daily Commuter, I am looking to build some "Reliable & Robust" 700C 32 hole eyeleted rims up using 2mm stainless plain gauge spokes thinking laced 3 cross. Will run 28C tyres at 95psi.
Have available stainless steel spokes with brass nipples so will grease the spoke threads before assembly and dot lube the nipples at the rim interface to minimise torque/tension scatter and stress relieve the spokes.
Dally commuter =>> 16 km each way with me 6ft 4" at 95kg kitted to ride + pack at 12kg = 107kg.
Went looking for guidance on kitted to ride weight over 100kg and spoke tensions
in my books "Zinn Road Bike Maintenance 3rd Ed ISBN 9781934030424" & "The Art of Wheel Building - Gerd Schraner ISBN 0964983532" .
=>> Noted comments but nothing specific
pg 11 Schraner "hubs rims & spokes….are primarily for racers and bikers weighing a max of 85kg".
pg335 Zinn " Building Wheels for Bigger Riders -…"
Reasons for wheel failures Thread - in particular ironhanglider » Sat Sep 01, 2012 8:30 pm "If I were to build a set of wheels for TLL …..The next best solution would be to tension them up higher and hope…he breaks them through some non-warranty mis-adventure before the rims cracked through fatigue."
I could get a new 36 hole rear rim & Hub but have 32 hole rims & hubs + all the bits available so keen to give a set of higher tension 32 Hole rims a go.
Have a Park Tool TM1 Spoke tension meter.
=>> Looking at the spoke tension card that comes with the TM1, I'm thinking that to cater for the commuter load I'll tension the spokes as follows:
Rear Rim Drive Side goal 27 +/- 10%
Rear Rim Non Drive Side 22 +/- 10%
Front Rim (Both sides) 27 +/- 10%
Anyone have experiences to share building eyeleted 700 C rims to "27 +/-10%" on the Park Tools TM1 Gauge = 156 kilograms force ie Kgf
Thoughts/experiences comments welcome.
I'm sure I read somewhere - prolly Roger Musson - that butted spokes are stronger than single gauge. IIRC it had to do with the way spokes change their tension under load, in use.
I built up a set of 32 spoke 700C wheels which ended up at the tension you describe a short while back, using butted spokes. Rims didn't have eyelets, but otherwise built up pretty much as you described. I'm a lot lighter than you, so can't offer any advice on that part of your question, but I wanted to be able to ride up and down kerbs, so my toughness requirement was not a million miles different from yours.
My bike blog. Long on rumination, rambling and opinion. Why let facts ruin everything?
Man that was hard to read.
I'm sure 32h will be fine whether you go for 2.0 or butted 1.8mm spokes, if it were me I'd be aiming for 115-120kgf on the rear DS with 3x lacing.
It'll be fine as long as the rim isn't a noodle and you keep an eye on even tensions.
Jobst Brandt also says this.
Sheldon agrees as well and he puts it into human language (as opposed to engineer-speak): "Double-butted spokes do more than save weight. The thick ends make them as strong in the highly-stressed areas as straight-gauge spokes of the same thickness, but the thinner middle sections make the spokes effectively more elastic, allowing them to stretch (temporarily) more than thicker spokes.
As a result, when the wheel is subjected to sharp localized stresses, the most heavily-stressed spokes can elongate enough to shift some of the stress to adjoining spokes. This is particularly desirable when the limiting factor is how much stress the rim can withstand without cracking around the spoke holes."
i'm103kg at the moment and have built some wheels, having she same interest in reliability whilst riding with a bit of luggage.
You probably won't go that high without taco-ing the rim. You've not stated what rim you will be using. Mavic specify 70-90kg in some places and 90-110kg in others for max spoke tension. DT Swiss specifies 120kg (actually 1200N) for their stronger rims. You might be able to use Velocity Deep Vees to get to 140kg, but you won't be making it that taut just to take your weight - it will be because you want to see that number on the meter. I've got some Deep Vees at 130-odd kg for my fixie, but they are the only wheels I have built that taut that feel like they aren't going to move.
I'd carry a pannier rather than/as well as a pack if over about 7 or 8kg - much more comfortable. I agree about the double butted spokes suggestion. Don't restrict yourself to a pre-calculated NDS spoke tension - just get it dished right with the DS spokes at a good tension. Your estimate may be near right, but getting the wheel geometry correct is most important.
2014 goal 52000m
I don't think there is much to worry about, just do a good job. I have very limited experience. I have built two rear wheels following Roger Musson's book with double butted spokes. I don't have a tensiometer or much experience, but just wound them up to something that felt nice and tight, actually the first try they were a bit loose and started to undo themselves but that was quickly fixed.
Both wheels have been perfectly reliable for over 10,000km. I am pretty heavy and commute with a pannier all the time and I think every new bike I've bought I've had some kind of problem with rear spokes breaking, so I've been really impressed at how easy it is to do so much better just by building them myself. Not sure how much is due to the butted spokes and how much to the building. Or it could just be luck.
I would definitely go 32H 3x with a ~30mm deep rim, eg. velocity deep v or dt Swiss rr585 (what I used). You will find those very hard to taco even at extreme spoke tensions!
+1 for double butted, though 2.0mm plain gauge should do the job.
One thing is the NDS spokes need enough tension so they don't unwind or break at the hub. I'm not sure the tension required to dish correctly is enough, but it doesn't miss by much, maybe an extra full turn of the nipple. Not having exact spoke lengths probably exacerbates it.
Good luck and have fun
Thanks for the thoughts they are appreciated.
Re - Crawf » Mon Oct 29, 2012 11:24 am
"aiming for 115-120kgf on the rear"
=>> That would be "25 = 121kgf" on the Park Tool TM1 for 2.0mm plain gauge, I have built wheels to this level before for the road bike. [FYI Ref Card with TM1 lists 24 = 107kgf, 26 = 137kgf, 27 = 156kgf, 28 = 179kgf]
Re - rkelsen » Mon Oct 29, 2012 11:58 am
"Jobst Brandt also says this. ….Sheldon agrees…."
=>> Noted "http://commutercycles.com.au/news/2010/hand-built-wheels/"
"The next issue with spokes is what gauge to use. On any wheel that will get serious use we will recommend butted spokes of some variety. One benefit of butted spokes is obvious – reduced weight. This is not to be sneezed at, since it’s rotating weight, but it’s certainly not the only reason to use butted spokes. Even without the weight saving we’d be using them for their mechanical properties. It’s counter-intuitive that a thinner spokes could make a stronger wheel, so you sometimes hear people talking like the weight saving is the only real benefit, and you even hear some people suggest that the weight benefit comes at the expense of strength. Some people build their touring wheels and MTB wheels with straight gauge spokes thinking they’re getting a stronger wheel, but it’s a big mistake.
Even though butted spokes are thinner in the middle than plain gauge spokes they make for a stronger wheel. The main reason for this is that the two ends of the spoke are concentration points for the stresses in a wheel. The shoulder of the spoke and the end of the threads are the two places where spokes most commonly break. A thinner middle section will flex more under the impact and so transmit less of the stresses to the weak points at the ends. This flex also means that the impact can be shared with more of the adjacent spokes. Both of these points add significantly to the fatigue life of the wheel."
Re - wqlava1 » Mon Oct 29, 2012 1:05 pm
"You probably won't go that high without taco-ing the rim."
=>> Hmm have built to 25 ie 121kgf on the Park Tool TM1 with MAVIC Open Pros and 2mm plain gauge spokes before.
"You've not stated what rim you will be using."
=>> Have two Mavic 2011 NOS Open Pro's in the Shed
http://www.mavic.com/en/product/rims/ro ... s/Open-Pro
=>> But have been looking at:
http://www.mavic.com/en/product/rims/ro ... rims/A-719
* The promo lit says "Bomb Proof" but I'm balking at the weight.
"Don't restrict yourself to a pre-calculated NDS spoke tension - just get it dished right with the DS spokes at a good tension. Your estimate may be near right, but getting the wheel geometry correct is most important."
=>> Agreed, key goal of even tension ie +/-10% goal
Re - Reman » Mon Oct 29, 2012 7:33 pm
"definitely go 32H 3x with a ~30mm deep rim"
"+1 for double butted, though 2.0mm plain gauge should do the job."
=>> Noted comments on "http://commutercycles.com.au/news/2010/hand-built-wheels/"
"There are only two real downsides to double-butted spokes, they are slightly more work to build with, and for wheels where stiffness matters at all costs (track and trials wheels) that last little bit of stiffness can be bought at the expense of longevity by using plain gauge spokes. "
Alternates to my Plain Gauge Spoke Suggestion??
a) DT Swiss Competition. double-butted 2.0mm at either end & 1.8mm in the middle.
b) Super Comps. triple butted 1.8mm at the threads, 1.7mm in the middle & 2.0mm heads.
Any other recommendations?
firstly thank you for reading my post, I was very proud that someone thought it worthy to be made a sticky.
However do realise that any comments with relation to TLL should not be applied too widely since he is a special case. I've never met the man but I have read the tales of the trail of broken bike parts that clutter the recycling bins of shops and factories around the world. The man can break hubs! I could only speculate as to why but the short answer is that he is big, strong and has a talent for breaking stuff. Some people have this talent, others don't. I've been racing on low spoke count carbon rimmed wheels for the last 6 years that supposedly had a weight limit of 80kg, I did get to 90kg in 2006 but I've been uncomfortably over 100kg for the last 3 years. I wouldn't recommend disregarding limits to anyone else though.
32 spoke wheels should be perfectly fine for a normal person of your dimensions, particularly with the larger tyres.
I gather that you have all the parts for the wheels already and I see no reason to change anything. Yes butted spokes are better, (they're not stronger, just less likely to break) but plain spokes have served adequately well under millions of bikes for many years. Yes deep section rims are stronger. Yes 36 spoke wheels are stronger. However unless you are another TLL in training what you've got sounds good enough to me.
I am concerned about the proposed tension though. You haven't specifically mentioned the rims, but there are not many makers of eyeleted rims around, and they are mostly European. Mavic in particular were known for having a low tolerance to high tension. Most European manufacturers tend to specify maximum tensions for their rims and at least at the beginning I'd recommend sticking to that. If you are prepared to build wheels in the first place then you shouldn't be turned off by the thought of re-tensioning them later. I really hate to see equipment broken before it's time and that'd be a greater likelihood with too much tension.
The symptoms of too high vs too low tension tend to show up in different ways. Way too high and you risk tacoing the wheel before you have even finished building it, otherwise at just a bit too high, the wheels will be quite ok, possibly even for a while, until the rim starts cracking which is both annoying and expensive. Many people will keep spare spokes around, but spare rims is a bit much.
If spokes don't have enough tension (and you lubricated the nipples before you built the wheel) the first symptom you are likely to see will be one or more NDS spokes loosening and causing a buckle. This is easily identified and the offending spoke can be tightened up to true the wheel quite effectively even mid ride if necessary. This would then give you the clue that more tension is required overall. Having identified this you can put a bit more tension on the whole wheel (being aware of dishing) and sneak up on a tension that will hold the nipples fast. If you you are at or near the stated limit of the rim then this is the time to decide whether to roll the dice by exceeding the recommended tension of the rim or by using a thread locker. Using a thread locker however just treats the unscrewing symptom and not the cause so you may find that the spokes are still more likely to break due to fatigue.
Too high = break rim = expense, major inconvenience, re build wheel
Too low = unscrew and perhaps break spoke = less expense, minor inconvenience, true wheel
I'd say that in the first instance you build the wheel with tensions that are close to what the manufacturer recommends, after all this could well be enough tension anyway. If you then find that you are getting symptoms of spokes that are too loose you can always tighten the wheel a bit more later. If it is really not up to the job and you start breaking spokes regularly, that'd be the time to build the 36 DB spoke Deep V's.
+1 gazillion to what Cameron said. Most excellent post sir!
156kgf sounds like quite a bit of tension to me, Correct me if I'm wrong, but most rims seem to have a max of around 130kgf?
Yes that's what I was referring to commenting that it would tend to taco rims or make them hard to get straight. I gave a couple of factory figures above off their tech doco. Sun Rims also specify a max of 1200N (about 120kg).
2014 goal 52000m
I totally agree. I built up a set of 32 spoke Dura Ace/Open Pros earlier this year at recommended tension, which despite not being used a lot yet, feel great for me at 6'4 and 90kg.
I have built up my commuter wheels with 32 spokes too, but higher tensions because they were spare parts that didn't owe me money and i was curious to see what would happen. They feel fine too, but a bit like a big hit could make them explode.
None have been any more or less reliable than the others, and i regularly take them down singletrack and launch up/off kerbs and speedhumps or anything else that gets in the way.
32 spokes is plenty if you build them right. Start overanalysing when your wheels show signs of struggling, but until then i would just play by the book and you should be fine.
How are those wheels going?
If you've got them, use them I say. I'm not convinced that the A-719s are stronger by anything other than more metal. If I was looking at rims at that weight I'd be looking for 30mm deep rims since they are stronger by virtue of their shape, and they increase the bracing angle of the spokes.
Years ago things were said to be bullet proof, now they say bomb-proof, but no-one is actually prepared to prove it.
I'm not sure of the veracity of the stiffness argument for plain spokes. Do any high level trackies use spoked wheels? I strongly suspect that straight spokes were observed in use and an assumption has been applied to why. I think that an alternative explanation is that these are two disciplines that have a high likelihood of breaking wheels though misadventure and it may simply be a cost/performance decision, with longevity lower on the priorities.
Sapim CX-rays are reputed to have the longest fatigue life. That being said are they worth the expense? 2.0-1.8-2.0 appear to be where the best value is be that from DT, Sapim, or Wheelsmith. Thinner than that in the middle and you start to get problems of spokes twisting as they come up to tension. I do not recommend any spokes with 1.8mm threads unless your whole fleet of bikes has that dimension. Principally because it is hard to pick the difference between the nipples for them and the more common 2.0mm threads. Since the thread pitch is the same it is easy to use the bigger nipples by mistake only to have the damn things strip when they come up to tension. (I got a mixed bag once and it drove me mad).
If you want to join me out on my limb I have recently ordered some Newson Sportec spokes which look like a similar design to CX-Rays but without the European Heritage and Mystique and also come in pretty colours similar to:
Be aware that they do two versions of Aero spokes 2.3mm ones which will go through normal spoke holes and wider ones which need slotted hubs.
I haven't even seen them in the flesh yet so I have no impressions at this stage. I will post up some details when the wheels are built.
Your last two sentences sum a lot of what I was trying to say very succinctly.
I'll also be interested in your long term experience with your high tension wheels. Have you had any rim failures from adventurous/enthusiastic riding yet? Potato chipped wheels always look impressive. Check in every 1000km on them and we'll see how long they last and the mode of failure when the time comes.
I wonder whether or not, since aluminium has no fatigue limit, if all aluminium rims will eventually form cracks around the spoke holes just that it happens sooner with more tension. Previously with rim brakes it is possible that many rims were retired through worn brake tracks before any cracks became obvious. Will the advent of disc brakes mean that rims will now actually last until the cracks develop?[/speculation]
I haven't had any issues at all, yet. I do ride my single speed roadie a bit like a mtb so i'm sure it is a matter of time until i misjudge something and they take a big hit. I've done a few thousand km with the high tension front and it is perfect still - haven't even needed to true it. I don't use that back wheel at all as I'm running a White Industries ENO for chain tension with a Deep V, and i think they will go forever... touch wood.
I think you are right about the rim brakes traditionally being more of a factor than the wheel build itself. Any decent handbuilt 32 spoke wheels should last.
Thanks for all your comments, thoughts and experiences they are appreciated.
I have built 700C 32 hole eyeleted rims up using 2mm stainless plain gauge spokes to "25 = 121kgf" on the Park Tool TM1 for 2.0mm plain gauge, before for the road bike.
I have rim brakes on the 25" frame commuter.
Parktools TM1 Spoke Tension Gauge Ref Card with TM1 lists for 2mm plain gauge spokes
24 = 107kgf,
25 = 121kgf,
26 = 137kgf,
27 = 156kgf,
28 = 179kgf
I have built the Mavic 2011 NOS Open Pro's as follows:
Rear Rim Drive Side goal 25 +/- 10%
Rear Rim Non Drive Side 22 +/- 10%
Front Rim (Both sides) 27 +/- 10%
Nipples were brass and lubricated. No stripping occurred or rounding off, I built the wheels up slowly in stages from 20 to 23 then onto 25 for the rear, and 27 for the front on the TM1 gauge. Stress relieving the spokes at each stage as I went, then let them sit for a week or so with temperatures varying from 10-40 Deg C. Stress relieved them again and rechecked the tensions in all spokes and reconfirmed the tensions.
Have since done approx 250km on them, they feel great to ride, very responsive. Rechecked the spoke tensions and compared with build tensions, all good.
The Park Tools TM1 measurements are very repeatable, which is great for the +/- 10% accuracy. Having previously built wheels by the flick the spoke for "ting" tension method, I cannot recommend the The Park Tools TM1 highly enough, it makes it so much easier to build straight consistently tensioned wheels.
The 700 x 28C tyres at 95psi and the 25" CroMo Frame help the ride to be very comfortable.
=>> WRT reliability lets see how we go, I'll be happy with >10,000km before the next build (out of interest I'll check the spoke tension every 1,000km or so & adjust if and when required to see the experiment out).
I also have another set of Mavic 2011 NOS Open Pro's siting in the shed for the next build.
Building the front wheel up to 156kgf sounds too high to me, thought the max spoke tension on the OP was 115kgf? I would think a target 90-110kgf on the OP would be more reasonable
90-110kgf for the OP is correct. That's what the Mavic Technical Manual suggests. I built up a set of Open Sports and went to around 100kgf (around 23 on the Park tension meter). 156kgf is indeed too high and potentially dangerous. With 32 spokes there's no need for such high tension and the rim won't take it.
Now before anyone says that higher tensions yield more stiffness I'm going to say it doesn't, I've been hearing that too many times and I am sick of it. With a high tension, the pre-tension on the spokes is increased, which means that fatigue sets in quicker, not a stiffer wheel. The stiffness of a wheelset is dependent on rim stiffness, spoke count and the brace angles. NOT by how over-tensioned your spokes are. As long as your spokes have an adequate tension and they don't go slack you won't notice an improvement in stiffness with a higher tension
When getting tensions within 10% it is not the same as getting the Park TM1 readings within +/-10% sat the meter is not linear. The OP's table a few posts back is ambiguous.
2014 goal 52000m
20 posts • Page 1 of 1
Who is online
Users browsing this forum: Dragster1