Originally Posted by
cyccommute
Well that doesn’t cut it.
I’ve been a mechanic and wheelbuilder (for myself) since 1980 for the former and 1986 for the latter. I’ve also been a clydesdale that mountain bikes and does loaded touring (on the road and over mountains) since before I started doing my own mechanical work. I know a thing or two that the “regular” cyclist doesn’t know about breaking spokes. Through my experience I’ve found that the common wisdom on wheels is usually wrong.
There absolutely is something wrong with the design and materials of the wheel. There are too few spokes to handle the load. The spokes are too weak and not elastic enough to handle the load. The type of rim means mostly nothing when it comes to wheel strength and durability. OEM wheels are often problematic for riders who are large and/or carry extra load. A 28 spoke wheel might work fine for a 170 lb rider who is a racer carrying nothing more than a couple of water bottles. Put a 200+lb rider on the bike and the 28 spoke wheels are more prone to having problems. Put an extra 60 lb of cargo on the bike and spoke breakage is almost guaranteed. Proper spoke seating and proper tension
are important but they aren’t the
only thing that are important.
The conventional wisdom on wheels is that you need the strongest rim possible and whatever spokes laying around. The conventional wisdom is wrong. Spokes are the things that break on wheels and spokes are the most neglected part of the wheel when wheels are being designed. A broken rim doesn’t spell the death of a wheel. Broken spokes do. If people concentrated on the spokes more than the rims, we’d have wheels that could stand up to clydesdale/utility use better. Sheldon Brown wrote about the Great Spoke Scam years ago.
Eric Hjertberg, founder of Wheel Smith,
advocated for stronger spokes about 10 years ago. I had been using those spokes for about 10 years before he wrote the article and I had already found what he was writing about years earlier. Going from even double butted spokes to triple butted spokes significantly reduced my spokes breakage around 25 years ago and I’ve used them (as well as advocating for their use) since then. A 28 spoke wheels
could be built that would handle heavier loads and utility riding but only if the straight gauge spokes of SamSam77’s OEM wheel were replaced with a triple butted spoke. I don’t quite agree with Hjertberg that the triple butted spoke is equivalent to adding 10 spokes but it is certainly equivalent to adding at least 4 spokes…maybe 6.
Another OEM wheel (or even a higher end wheel) is unlikely to solve his problem. A 36 spoke replacement wheel would help although it still has the same weak spokes.
Yes, this is a warranty problem. I will say that he has run up against the problem with going the on-line purchase route. Buying from a shop would give him a bike with some backup rather than having to deal with someone remotely. I, and probably you, don’t need to go to a shop because I probably know more about my bike and how to fix it than the mechanic at the shop does. That is especially true if the bike is older, although that is not SamSam77’s problem
Better yet would be to find someone who will show you how to do it so that SamSam77 can start down the path of learning how to take care of his own bike and/or build better wheels.
You have been learning from trial and error, and through that process came to some mistaken conclusions.
I was taught how to build wheels by a graduate of the Wheelsmith wheelbuilding course. I have built, warrantied, trued and repaired many more wheels than you have - and the vast majority were straight gauge 14g spokes. An incredible number of those wheels had only 20 spokes per wheel.
The advocacy for heavier elbowed spokes was for machine built wheels because the elbows were not going to be hand seated, and the heavier elbows protected the spokes a little bit better. But if you are seating the elbows, that isn't necessary because the bend is not being constantly stressed. I have a wheelset that I have been riding for a decade that is 28h and 15g unbutted spokes. 14g are more than up for the challenge of building a wheel if the rim is sufficiently stiff. Not if you are using 280 gram box section rims, though.
Originally Posted by
LV2TNDM
Good synopsis, but I disagree with part of #1. These wheels were most likely built with the cheapest barely-stainless steel straight gauge spokes the product manager could find. "Stainless spokes from an Indian metal scrap yard? I'LL TAKE 'EM!" (And Formula hubs are pretty low grade too, but acceptable.)
If these were my wheels, I'd rebuild them with quality butted spokes and brass nipples. Obviously lube the nipples & threads with boiled linseed oil. I'd then build them with nice even tension, nice and high so the lower tension side is well above minimum. All while properly seating & cold setting the spokes in the hub flanges. Lots of "pre-stressing" the wheel and then eliminating any spoke wind-up at final truing.
Replacing garbage OEM spokes and building the wheels well will be the best way forward. Just getting a replacement wheel will find the OP in the same place in about 800 miles.
Or have a whole new custom wheelset built at $$$$.
What do you think 'good' spokes are made of? The stainless steel used is an alloy which is not strong - its main qualities are resisting rust and forming nicely. It has no hardening alloys. I haven't seen an unplated spoke rust in 30 years. Spokes are not made of a magic alloy, they are made of a somewhat soft and malleable one. The OP has already told us what the problem is - low and uneven tension. Why conclude that an obvious tension problem is a metallurgical problem.
I don't know where so many people have accumulated the knowledge that makes them want to replace all the spokes every time there is a tension issue, but it seems to be from reading posts on forums - not working as a mechanic. When properly built, the spokes will be the last thing to fail on a rim brake wheel.
Replacing all the spokes and the (already brass) nipples will cost $30+ per wheel plus $40 labor per wheel. At that point you could buy some new wheels for just a few dollars more.
And I am all for learning to work on bikes, but you don't do that by starting with screwed up stuff. That leads you down the path of erroneous conclusions, like Cycomute's. Either learn from someone who knows what they are doing, or start with mostly new components of the correct dimensions and keep control of all the steps. The OP has a problem that needs solving right now, and a pro adjusting his existing spokes is the simplest and least expensive path forward. Why do you guys always want everything to be harder than it needs to be?