Need Advice About Stronger Wheels

jeepguy32 said:

[font=Arial]I recently bought a trailer to pull my 80-pound Black Lab behind me when I ride. I hook the pooch up to a Springer Dog Jogger [/font][font=Arial]springerusa.comspringerusa.comOpen ↗[/font][font=Arial] for a couple of miles, or for help up a big hill, then he gets in the trailer and I return the favor. Our plan is to eventually do some touring. For example our Autumn 2008 goal is a round trip on the 225-mile "Katy" trail across Missouri. [/font]

[font=Arial]Since I began using the trailer I'm breaking rear spokes constantly. I need advice on how to handle the problem. I know I need to upgrade my rear wheel, but to what? I can't afford a $2,000-$4,000 true touring bike right now, so I'm making due with a four-year-old Giant comfort bike. It's actually been a great 'round town bike, which I've really enjoyed. But the extra stress from the trailer keeps breaking spokes on the stock 32 spoke rear wheel. What I'm after here is a heavy-duty-won't-leave-me-stranded-out-in-nowhere solution. The weight of the new components is not critical...reliability IS. Also, will I be able to reuse any of the cassette sprockets or the freehub? Any advice is appreciated![/font]

I suggest a new rear wheel with more spokes, strong/stiff rim, and a good quality build.
36 spokes minimum, 40 or 48 spokes wouldn't hurt but are harder to find rims and hubs for those spoke counts.
I also suggest looking at a way to get some of the weight of your touring load moved up front. When I do long distance camping tours I put about 20 pounds on the front and 20 pounds rear.
I build a significant number of wheels for heavier riders. I use mostly Velocity Dyad and Synergy rims. Both are suitable for heavy loads. Synergy rims are available with Off Center spoking for rear wheels to help with better spoke tension balance. Better spoke tension balance helps both sides of the rear wheel's spokes share the dynamic loads. Spreading the dynamic loads better increases spoke fatigue life. Good quality build in general using good quality components will insure much improved wheel durability.
David Ornee, Western Springs, IL
dave at ornee dot net

Where/how are the spokes breaking? Is it just under torque loads or when hitting a bump?
More spokes the better! And I stand by my belief that butted spokes with thick elbows and threads are stronger than straight gauge.
Don't go for light weight anything (except butted spokes, but get the ends as thick as you can). DA hubs have got a fantstic rep, but super light weight hubs may break free wheels or flanges. Use brass nipples not Al (so you don't strip a thread).
You should be able to source 40 hole hubs and rims since a lot of tandums use them, but you may struggle to get 10 speed hubs as tandums tend to stick to 8 or 9 speed for the stronger chains.
Any rim with a rep for being strong with enough spoke holes will likely be ok. Don't go lite weight! The tension in the large number of spokes requires a good cross sectional thickness to take the compressive loads created in the rim.

Stick with good quality brands, don't go light weight, and get it custom built by a pro. The wheel should then take years of heavy use. But also don't forget to get them serviced. If spokes loose tension the wheel may not go out of true due to the other spokes around them, but then still break the spoke.

Phill P said:

Where/how are the spokes breaking? Is it just under torque loads or when hitting a bump?
More spokes the better! And I stand by my belief that butted spokes with thick elbows and threads are stronger than straight gauge.
Don't go for light weight anything (except butted spokes, but get the ends as thick as you can). DA hubs have got a fantstic rep, but super light weight hubs may break free wheels or flanges. Use brass nipples not Al (so you don't strip a thread).
You should be able to source 40 hole hubs and rims since a lot of tandums use them, but you may struggle to get 10 speed hubs as tandums tend to stick to 8 or 9 speed for the stronger chains.
Any rim with a rep for being strong with enough spoke holes will likely be ok. Don't go lite weight! The tension in the large number of spokes requires a good cross sectional thickness to take the compressive loads created in the rim.

Stick with good quality brands, don't go light weight, and get it custom built by a pro. The wheel should then take years of heavy use. But also don't forget to get them serviced. If spokes loose tension the wheel may not go out of true due to the other spokes around them, but then still break the spoke.

Firstly, 14/15/14 butted spokes have the same width at the elbows as straight 14G spokes.

Secondly, you dont need 10 speed specific hubs to fit in a 10spd cassette. 10 spd casettes fit on "9spd" hubs fine, they normally come with a spacer that needs to be fitted.

Hmm anyone that you pay money to build a wheel for you is a pro. But thats hardly an assurance of a quality built wheel.

I would suggest doing a search on the threads here, there is more than enough to point you in the right direction as to the qualities of a strong reliable wheelset.

Most would agree that a higher spoke count would give you a more reliable wheel. 36H hubs, and rims are probably more commonly found that 40H ones. Its more important that the wheelbuilder you find knows what they are doing, and the wheelbuilder would probably be able to offer you good advice regarding your wheel needs.

I've never toured on 700C, but if I were planning to do so, I wouldn't trust 36 spokes - I'd want more.
If you want more bombproof touring wheels, consider going to 26"/559mm - an old rigid MTB would not be expensive.

40, 48 hole hubs may be 140mm wide OLD.

jeepguy32 said:

[font=Arial]I recently bought a trailer to pull my 80-pound Black Lab behind me when I ride. I hook the pooch up to a Springer Dog Jogger [/font][font=Arial]springerusa.comspringerusa.comOpen ↗[/font][font=Arial] for a couple of miles, or for help up a big hill, then he gets in the trailer and I return the favor. Our plan is to eventually do some touring. For example our Autumn 2008 goal is a round trip on the 225-mile "Katy" trail across Missouri. [/font]

[font=Arial]Since I began using the trailer I'm breaking rear spokes constantly. I need advice on how to handle the problem. I know I need to upgrade my rear wheel, but to what? I can't afford a $2,000-$4,000 true touring bike right now, so I'm making due with a four-year-old Giant comfort bike. It's actually been a great 'round town bike, which I've really enjoyed. But the extra stress from the trailer keeps breaking spokes on the stock 32 spoke rear wheel. What I'm after here is a heavy-duty-won't-leave-me-stranded-out-in-nowhere solution. The weight of the new components is not critical...reliability IS. Also, will I be able to reuse any of the cassette sprockets or the freehub? Any advice is appreciated![/font]

If your giant has a Shimano rear hub, find a local wheelbuilder who has a good reputation, and have him lace a Sun CR-18 rim or something similar onto it.

The key thing is the quality of the wheelbuild not the number of spokes.

Retro Grouch said:

If your giant has a Shimano rear hub, find a local wheelbuilder who has a good reputation, and have him lace a Sun CR-18 rim or something similar onto it.

The key thing is the quality of the wheelbuild not the number of spokes.

However, if you are buying a CR18, spokes, and wheelbuilding service, the cost of a reasonable quality 36-hole hub will not add a large percent cost to the project. Plus, 32 vs 36 may not be everything but the number of spokes is important.

garage sale GT said:

However, if you are buying a CR18, spokes, and wheelbuilding service, the cost of a reasonable quality 36-hole hub will not add a large percent cost to the project. Plus, 32 vs 36 may not be everything but the number of spokes is important.

I certainly may be wrong...it's been known to happen, but it seems intuitive to me that increasing the number of spokes does have strength benefits to a wheel. I'm sure proper wheel-building plays a large roll in wheel strength, but how many 32-spoke wheels do you see on the rear of tandem cycles?

Just to clarify, I'm 250 pounds, the trailer is roughly 30, and the dog is 80 (you do the math). The dog often positions himself in a way that much of his weight is on the rear cycle wheel and not on the trailer wheels (I can feel the resistance change as he moves his weight from the lower PSI trailer wheels to the higher PSI bicycle wheel). I haven't even started adding the weight of the camping equipment to the equation.

jeepguy32 said:

I certainly may be wrong...it's been known to happen, but it seems intuitive to me that increasing the number of spokes does have strength benefits to a wheel. I'm sure proper wheel-building plays a large roll in wheel strength, but how many 32-spoke wheels do you see on the rear of tandem cycles?

Just to clarify, I'm 250 pounds, the trailer is roughly 30, and the dog is 80 (you do the math). The dog often positions himself in a way that much of his weight is on the rear cycle wheel and not on the trailer wheels (I can feel the resistance change as he moves his weight from the lower PSI trailer wheels to the higher PSI bicycle wheel). I haven't even started adding the weight of the camping equipment to the equation.

Let me clarify that I don't agree that Retro's idea is a particularly good way to strengthen up your wheel, regardless of whether you use 32 or 36 spokes, because of the cost. You will be very close to the cost of a new rear wheel if you go that route.

If you DO buy a wheel, you will be able to use your cassette (the sprockets and spacers are riveted together in a unit). Wheels usually come with freehubs.

I have no specific knowledge of strong 700c wheels (or weak ones for that matter). The 29" mtb wheels actually have 700c rims but may have 135mm wide rear hubs. I don't know if your bike has 130 or 135mm rear spacing. Determining the spacing should be step one in selecting a new wheel. It is the dimension between the insides of the rear frame, right by where it's slotted for the axle. Another way to put it is it's the width of the hub not counting the axle or the quick release skewer or nuts which go on the outside of the frame.

garage sale GT said:

Let me clarify that I don't agree that Retro's idea is a particularly good way to strengthen up your wheel, regardless of whether you use 32 or 36 spokes, because of the cost. You will be very close to the cost of a new rear wheel if you go that route.

If you DO buy a wheel, you will be able to use your cassette (the sprockets and spacers are riveted together in a unit). Wheels usually come with freehubs.

I have no specific knowledge of strong 700c wheels (or weak ones for that matter). The 29" mtb wheels actually have 700c rims but may have 135mm wide rear hubs. I don't know if your bike has 130 or 135mm rear spacing. Determining the spacing should be step one in selecting a new wheel. It is the dimension between the insides of the rear frame, right by where it's slotted for the axle. Another way to put it is it's the width of the hub not counting the axle or the quick release skewer or nuts which go on the outside of the frame.

Thanks for the info, GT. I'm going to get some more advise from my LBS later this afternoon, but here's what I think I may do:

* Rim - Sun Ryno Lite 26" x 27.5 mm (36 Drilling)
* Hub - 36 Hole Shimano Deore LX
* Spokes - DT Alpine III Triple Butted (2.34/1.8/2.0)

Of course built by a reputable wheel builder. What do you think?

jeepguy32 said:

Thanks for the info, GT. I'm going to get some more advise from my LBS later this afternoon, but here's what I think I may do:

* Rim - Sun Ryno Lite 26" x 27.5 mm (36 Drilling)
* Hub - 36 Hole Shimano Deore LX
* Spokes - DT Alpine III Triple Butted (2.34/1.8/2.0)

Of course built by a reputable wheel builder. What do you think?

Rhyno Lites are very tough rims. Their downside is they are among the most difficult to install tires onto. that's why I suggested the CR-18. The section looks about the same so it's still a tough rim but it's 5mm narrower and tires are easier to install.

You need to double check to be sure that the spoke holes in the LX hubs are big enough for the Alpine spokes.

A wheel built with stout components by a moron won't be nearly as strong as one built of lighter parts by a good wheelbuilder. The builder is by far the most important factor and, whenever I read somebody's list of components, I wonder if they are skimping that part.

jeepguy32 said:

Thanks for the info, GT. I'm going to get some more advise from my LBS later this afternoon, but here's what I think I may do:

* Rim - Sun Ryno Lite 26" x 27.5 mm (36 Drilling)
* Hub - 36 Hole Shimano Deore LX
* Spokes - DT Alpine III Triple Butted (2.34/1.8/2.0)

Of course built by a reputable wheel builder. What do you think?

Be sure to check the cost of just getting a new wheel. If you want to be as sure as if you got that reputable build, pay them to tension and true it. It may come out cheaper.

Say, what's your current rim diameter and rear spacing now?

thomas_cho said:

Firstly, 14/15/14 butted spokes have the same width at the elbows as straight 14G spokes.

Hmm anyone that you pay money to build a wheel for you is a pro. But thats hardly an assurance of a quality built wheel.

Yes 14/15/14 butted spokes have the same elbow as straight 14 gauge spokes, but butted spokes are more elastic/less stiff and hence allow load to be spread over more spokes, creating less overall stress in each individual spoke. Less stress in the spoke, stronger wheel.

Quite right. I meant PRO as in somebody who makes a living and has a reputation for being a good wheel builder.

jeepguy32 said:

[font=Arial]I recently bought a trailer to pull my 80-pound Black Lab behind me when I ride.... [/font][font=Arial]Since I began using the trailer I'm breaking rear spokes constantly. I need advice on how to handle the problem. ...[/font]

All you really need is better spokes and hand-assembly, but a lot of OEM rims are really cheap as well. And the kicker here is that the labor involved in lacing and truing a wheel begins to approach what an already-built wheel would cost anyway.

You can go to the shop and ask what it would cost for a better rim and spokes on the hub you've got, but you should also just ask them to see about getting a better-quality rear wheel (already assembled) and have the LBS hand-check the spokes.

If you upgrade the whole wheel, I'd suggest you get 36-spoke and at least Shimano XT hubs or better.
~

[font=Arial]Okay. Thanks for everyone's advise. Here's what my LBS suggested:[/font]
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[font=Arial]* Rim - Mavic XM 719[/font]
[font=Arial]* Shimano Deore XT 36H Hub[/font]
[font=Arial]* Straight 15-Guage Spokes[/font]
[font=Arial] [/font]
[font=Arial]The wheel built with these components was quoted at about $180.[/font]
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[font=Arial]I still have concerns regarding the straight spokes and I may insist that they use butted spokes of some sort. "Phill P" has already mentioned how butted spokes actually add strength to a wheel, not by being INDIVIDUALLY as strong as straight spokes, but through elasticity which allows neighboring spokes to team-up against the forces a wheel is required to handle.[/font]
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[font=Arial]I read this same sort of explanation from Sheldon "Wheels" Brown of Harris Cyclery in West Newton, Massachusetts (outlining Boston area). Mr. Brown, a lifelong bicycle enthusiast and regular contributor to Adventure Cyclist magazine writes with regard to spokes:[/font]
[indent][font=Arial]Double-butted spokes are thicker at the ends than in the middle. The most popular diameters are 2.0/1.8/2.0 mm (also known as 14/15 gauge) and 1.8/1.6/1.8 (15/16 gauge).[/font]
[font=Arial] [/font]
[font=Arial]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.[/font]
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[font=Arial]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.[/font]
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[font=Arial]Triple-butted spokes, such as the DT Alpine III, are the best choice when durability and reliability is the primary aim, as with tandems and bicycles for loaded touring. They share the advantages of single-butted and double-butted spokes. The DT Alpine III, for instance, is 2.34 mm (13 gauge) at the head, 1.8 mm (15 gauge) in the middle, and 2.0 mm (14 gauge) at the threaded end.[/font]
[font=Arial] [/font]
[font=Arial]Single- and triple-butted spokes solve one of the great problems of wheel design: Since spokes use rolled, not cut threads, the outside diameter of the threads is larger than the base diameter of the spoke wire. Since the holes in the hub flanges must be large enough to fit the threads through, the holes, in turn are larger than the wire requires. This is undesirable, because a tight match between the spoke diameter at the elbow and the diameter of the flange hole is crucial to resisting fatigue-related breakage.[/font]
[/indent][font=Arial]Brown's entire article can be found at this link:[/font]
[center] [/center]
[center][font=Arial]sheldonbrown.comwheelbuild.htmlOpen ↗[/font][/center]
[font=Arial] [/font]
[font=Arial]In his article he also addresses the "The Great Spoke Scam" of the early '80's, where manufacturers cut costs by using fewer spokes but sold the idea to the public as an upgrade. It's worth a read.[/font]
[font=Arial] [/font]
[font=Arial]Back to my wheel issue, I think I may have to insist that my LBS use the DT Alpine III Triple Butted (2.34/1.8/2.0) spokes I mentioned earlier in my thread.[/font]
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[font=Arial]I continue to welcome more advice and thoughts. I haven't pulled the trigger on this wheel build yet.[/font]