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MountainBikeReview.com's Forum Archives - Trials
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spokes butted vs. non-butted, 3x vs. 4x ?? (13 posts)
|  spokes butted vs. non-butted, 3x vs. 4x ?? | grandma
Dec 21, 2001 8:17 AM | | hi,
for a rear wheel (STOCK BIKE) that will be used for dirt jumping / trials /street what would be the best??
I am wondering why all the BMX wheels are 4x. They already have that many spokes and small wheels which itself should make a fairly strong wheel. Is there a real benefit from 4x spokes??? As far as I know the 20" trial bikes (mods) use 3x and less spokes than BMX wheels.
Someone said that straight 2.0 spokes make a stiffer wheel and I should not go with butted ones.
But from what I heard the butted (2.0/1.8/2.0) are better because they flex and therefore are more fatique resistant.
Any comments are very appreciated.
Thanks in advance
grandma |
| re: spokes butted vs. non-butted, 3x vs. 4x ?? | OrBust
Dec 21, 2001 11:28 AM | | I dont think you can run 4x on a 32 spoked wheel...its has to be 3x. 4x is only good on a 36. 20" mod bikes use 36 spoke, my mod wheels were laced up 4x. |
| re: spokes butted vs. non-butted, 3x vs. 4x ?? | Dingus
Dec 21, 2001 11:40 AM | | I looked for the same info before at the DT site and this is waht the founder of DT was saying. Supposedly the closer to 90 degrees that the spoke leaves the hub at the better(stronger) the relation of the hub to the rim, but then he goes on to say that in todays world of modern technology and better built components there isnt a real benefit to 4 cross, Im about to lace a 36 spoke wheel and Im gonna do it 3 cross, I dig having shorter spokes too.
As for butted or not I would say butted. Individually straight spokes are stronger than butted- pretty sure, well you would think right?- but when laced up the butted make a stronger wheel because instead of an individual spoke carrying the entire load of impact it stretches and spreads the force out over a larger portion of the rim and thereby the nearby spokes as well. Kinda like 4 weak guys could beat up 1 tuff guy- but it would be close. There doesnt seem to be a one best way to do anything, or even a best way. Just build it strong. |
| re: spokes butted vs. non-butted, 3x vs. 4x ?? | Surfboard921
Dec 21, 2001 1:18 PM | | 36spokes, 4x lace, straigt(non-butted) spokes
thats the best, I build my own wheels(plus the ones I've build for other people and the ones at the bikeshop where I work(I'm a mechanic)) and let me tell you that this setup IS the strongest. It's not the lightest of course, but who cares? 36spokes because it will be stiffer and you can lace 4x (you can't with 32), 4x lace because there are more contact between spokes, making it stronger and stiffer, and finally straigt spokes because impacts are distributed evenly across them, making them more resistant, butted spokes are lighter and looks cooler tho(if that matters to you). Just don't try to lace a 32 wheel 4x because at the flange of the hub, the spokes will be one over the other(head of the spoke) making a curve in it right at the base. |
| Respectfully disagree.... | Fabulous
Dec 21, 2001 3:21 PM | | There's an ongoing debate about spokes, and which are stronger- butted or straight gauge. Gerd Schraner, one of the world's best wheel builders and author of The Art of Wheelbuilding, says that he will only build on butted spokes, because the thinner mid section of the spoke flexes more, taking stress off the elbow of the spoke, which is where breakage occurs 99.9% of the time. I'm also a shop mechanic, and I can say that I have never seen anyone come in with spokes broken in the middle. There's a type of bolt, the name escapes me right now, that's used in machinery that takes a lot of vibration, and the middle is thinner than the ends so that the bolt can flex without snapping, while remaining just as strong at the threads. Same idea. Also, here's a quote from an article by Sheldon Brown, who is also a very experienced mechanic:
"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. This allows 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 hole."
Both these sources agree with the above poster about the number of spoke crosses.
The ultimate fact is that the parts of a wheel are not strong individually. Sit on an unbuilt Rhyno Lite and it will collapse. What matters is the way the wheel is put together. Spokes have to be evenly and properly tensioned, the spoke heads need to be sitting firmly in the hub flanges, and the wheel needs to be stress-relieved and re-trued at least 5 or 6 times during the building process. The builder is far more important than the components.
Hope this helps-
Nick |
| Interesting | Surfboard921
Dec 21, 2001 6:51 PM | | I had never heard about that effect of the butted spokes on the elbow of the spokes,it sounds very logic to me.
"The builder is far more important than the components."
I especially like that part;) |
| Respectfully disagree.... | Tommot
Dec 22, 2001 11:50 AM | | see www.wheelpro.co.uk (i think) and he seems to know what hes talking about. he says 3X definitely, and always use butted spokes. pretty much just what L7 said. |
| Respectfully disagree.... | Surfboard921
Dec 22, 2001 3:31 PM | | They say 3x of course, because just like the guy on dtswiss.com these books are made and think to touch as much poeple as possible, and they do that by talking about the majority of riders riding style which means they gotta reccomend the wheelbuilding for "conventional riding" like simple cross-country or road bikes (or hybrids etc). But trials isn't exactly conventional riding heh... Obviously it's almost impossible to taco a well built 32h 3x wheel just from riding cross country under "normal circonstances" unless the rider crashes very hard, do it on purpose or really really suck. But again, trials is not the same, it puts a lot more stress on wheels (from drops etc), and a 4x lace helps to absorb impacts. 4x is not absolutely necessary, it's just an added strenght. A good proof that 4x is stronger is tandem wheels(which is another "unconventional type of wheels" by the way) most of tandem wheels are 36h(or more) and 4x because they must be able to take the weight of 2 riders without getting out of true. As I said, 4x is just added strenght, 3x could do fine. But hey, DH'ers could wear normal helmets instead of full-faces and they would be fine too...until they crash. Thats the same with spokes crossing.
Just my opinion. |
| Thanks for the input | grandma
Dec 23, 2001 12:06 PM | | really appreciate all the input from you guys. Thank you.
I did some research myself and butted spokes seem to be the way to go as long as they are not too thin in the middle.
Instead of breaking (normally the head area of the spoke breaks) or even causing crackles around the spokeholes of the rim butted spokes will share the force applied to them with neighbouring spokes making themselves (and the rim also) stronger in fact, not a single spoke but when laced into a wheel that is.
I am still not sure whether to go 4x or 3x. I have 36 holes hub and rim but I am not quite sure if there is a real benefit and it would be a little more weight as well. |
| disagree about spoke crossing too | ohio
Dec 24, 2001 11:31 AM | | 4 x is used in application where an extreme amount of torque is being applied from the hub to the rim, such as tandmes (force of two people pedalling) or DH (force of 8" discs at 45 mph), but has no influence on the lateral strength of a wheel, which is the factor that is tested in trials. Rarely do trials riders rip spokes out of a rim on their own. It's almost always a result of the wheel folding sideways, that THEN breaks rims and spokes.
In fact the lacing pattern that is strongest and stiffest laterally is RADIAL because it uses shorter spokes than crossed patterns and they are oriented directly in-line with the forces experienced by the wheel. Radial spokes can't handle torque though which is why you can't use it in the rear if you plan on pedalling. 3x has proven itself to be the ideal compromise of pedalling response and lateral stiffness, and unless the wheel feels somehow soft for pedal kicks or other hard pedalling, there's no good reason to go 4x.
Also, spoke crossings don't have any additional strengthening or stiffening effect unless they've been tied and soldered, which will give you similar or greater stiffness than a radial wheel.
So my rec would be 36 spoke 14/15 3x, and if you're builder will do it tied and soldered (although that makes spoke replacement tougher). |
| The "best" setup | Trials4me
Dec 28, 2001 10:51 PM | | IMHO, I'd say the best trials setup would be 36 spokes laced 4x, with 14/15 on the left & 13/14 on the right. This results in a incredibly strong wheel b/c you have the strength of 36 spokes, the strength of 4x, plus the strength of butted spokes, PLUS much more even left side to right side spoke tension.
I've built a couple rear wheels this way for a friends bike and myself and both of us have never had to true the wheel more than maybe a 1/4 - 1/2 turn (after a crash or something) at most after the 1st week or so.
The entire wheel is believe it or not just about the same weight as a 32H 3x 14g setup, (which is still strong mind you, but relatively much weaker) and it looks bomber. |
| I've spent some time researching this one... | go-ride.com
Dec 28, 2001 8:45 PM | | our little shop has built over 200 downhill wheels this year and will probably build about 400 next year. Almost every one of our wheels is built for downhill racing, aggressive freeriding or extreme stunt riding. Nearly every wheel we build uses 14g spokes and 3X.
Over the last couple of years numerous riders have asked for all sorts of different lacing patterns and spoke types. Again and again we go with the 14g 3X because we know it works for our applications. However, I am one to find out the absolute best and test it whenever possible. So, the last 2 years in a row I have harassed the top wheel techs at both DT and Wheel Smith about the best way to build a DH wheel.
Well...after enough questions and persistence both camps finally admitted that 14g 3X is what they have found to be the best for DH wheels. I was taken back a bit. I asked about 4X, Double Butted spokes, oversized butted spokes and anything else I could come up with. The bottom line was that DB spokes build long lasting XC light wheels. The butting both saves weight and allows the spoke to flex along its whole length to minimize the chance of spokes breaking at the bend and nipple. However, this is a benefit that is only achieved over years of use. For wheel abusers this is not really a concern. If you can get a wheel set to last a full season of DHing you have done very well.
On the negative side is that DB wheels do have more flex and are more likely to taco under large loads. 14g spokes make for a stiffer wheel that is more likely to dent the rim edge than fold the wheel. Of course much of this information is based on building with a strong rim. If you use a light rim and 14g spokes you probably won't be able to get the tension up high enough to benefit from the extra impact strength of the 14g spokes.
How does this apply to trials wheels? I don't know? I suppose it depends on riding style and rim choice.
Scott C
go-ride.com |
| Finally the truth ! | wheely30km
Jan 7, 2002 6:45 AM | | I'm building my own wheels for 10 years, tested different spokes, spoke patterns, rims. What I found is:
- Radial lacing: It's so stiff, but too stiff: I saw once a guy with a radial front wheel, going down a compression, and his wheel exploded due to the (vertical) force. 3 days of coma ! the force applied to the flange of the hub is perpendicular and concentrated on the same point, making it a lot more fragile !
- double butted spokes are lighter. Maybe they can be more fatigue resistant. They can flex (=elongate) instead of breaking. But if they flex more, it gives a softer wheel, more subject to bend. And because the rim is not flexible, if the shock is too important, it will bend instead of flex. So straight gauge spokes are better for trials. Scott C from Go-ride got from DT mechs that 14 straight gauge is stronger, but maybe the spoke manufacturers wants to sell their DB spokes: they are more expensive so they earn more ?
- Breaking spokes ? when did it happen to you ? During more than 13 years, I broke about 2 spokes, but bent much more rims. I don't care about breaking spokes, I prefer a stiff wheel !
- cracked spoke hole ? it's often because some spokes are not enough tighten, so all the force is transfered to the well tightened ones, resulting in too much force. It's better to have all the spokes well tightened. A "plus" is of course a rim with eyelets.
And of course, a 36 spokes wheel is stronger than a 32, and x4 is stronger than x3.
So yes, the strongest is 36 spokes, straight gauge, x4. So yes, Scott C. from go-ride and Surfboard921 are right. |
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