Spokes

[rebeccmeister]

Right after I wrote that post on Saturday morning, I flipped over Froinlavin to spend a bit more time truing the rear wheel, and promptly discovered that I'd broken a spoke. So that explained the strange noise right as I left the house.

I'm not especially surprised, given how loose the non-driveside spokes were. I was planning on meeting up with my friend J for our ride at 10:30, so I called and suggested we meet up at the Local Bike Shop of Ambivalence, to see if I could get the spoke replaced and on the road, or figure out if I'd need to swap bikes and ride the Jolly Roger instead. One way or another, I was determined to get in a decent brevet training ride, and a broken spoke shouldn't be the showstopper.

A mechanic at the LBSoA was able to work on it immediately, and did a decent job, although I was pretty amused by his suggestion that I replace my patched tube with a brand-new tube. [I had no problem with his suggestion to replace the rim tape, although I should have double-checked what kind he wanted to put on there. I also temporarily ignored his aghastness at the quality of my rear brake pads. As a friend says, never buy a car mechanic's car, or a bike mechanic's bike.] While I was there, I figured I'd pick up some additional spokes, and got a bunch of spare patches, too.

And so, after the conclusion of our 120-mile training ride adventure, while putting things away, I noticed - yep. Another spoke has broken. This isn't too surprising. I'll replace that one myself. I just have to hope I don't have to repeat this process too many more times.

But it's all making me wonder - are these problems my fault, and is this the wrong wheel for me? The wheel came with the road bike, and with a 3-year warranty, so I'll bring the wheel back up to the shop in Seattle in April. At the same time, it is true that I've put substantial "crazy" loads on the bike, in more than one way. I hauled a load of compost in the bike trailer (causing a friend to comment that she saw the wheel flex when I started to pedal). I've toured on it a couple of times, and I wouldn't exactly call it "light touring," even though I've certainly toured with much heavier loads. I haven't been riding it on any especially gnarly terrain, unless you count Texas chipseal as gnarly terrain, and even before all of this I've had to re-tighten loose spokes pretty frequently.

So, maybe it's time to shop for a more beefy rear wheel. There are so few bike shops that actually understand these kinds of problems, because (1) the vast majority of them stereotype me as a dainty woman rider (oh honey), and (2) the "racer" culture is always harping on and on about lightweight and aerodynamic stuff. Yeah, efficiency matters, but it's pretty damn inefficient to have to stop and replace spokes every hundred miles. Just ask that guy who was touring around the Pacific Northwest on a pennyfarthing, having to replace multiple spokes on a daily basis. [I wish I still had a link to his blog - that guy was crazy! ha.]

Comments

[randomdreams.livejournal.com]

It's possible the heavier loading has fatigued the spokes and they're all going to fail, one by one. I'm thinking either respoke the wheel entirely with 14-15-14's, or find a 32 spoke wheel (or 36 if you can locate one.)
What type of wheel/spokes do you currently have?

[rebeccmeister.livejournal.com]

I'm so glad you asked, because you motivated me to leap up and replace the second broken spoke. The second broken spoke was adjacent to the first one, of course...and the whole reason I asked for multiple spokes when I got the first one replaced was that I figured the remaining spokes would be pretty stressed after the first one broke. I had a lot of, uh, fun? going through and replacing something like 6-8 spokes on my old Schwinn cruiser when that wheel started to die, and it set the standard for what I expect when spokes start breaking. :-)

Anyway, I don't know the spoke gauge (or how to check), but it's a 32-spoke wheel, so one might think it would be adequate. I'm definitely going to take the wheel back up to Seattle with me in April, because the bike/wheel-builders have a 3-year warranty on the wheels they build. I'm really quite surprised at the trouble this rear wheel has given me, considering that the shop that made the bike is pretty careful overall about the quality of work they do. I have a feeling they'll have good recommendations on how to proceed.

[randomdreams.livejournal.com]

What's the hub? There was a big run on straight-pull spoke wheels for a while, but it turns out that most of the designs break spokes like spaghetti.
There are hubs that seem to like breaking spokes. I don't know why.

[rebeccmeister.livejournal.com]

You know, I couldn't find any brand info on the hub, so it might just be something generic. I suspect the shop would have used something sensible, all in all, but then again I didn't care for the tires they stuck on the bike - they (Kendas) wore out quickly.

And yeah, I have passing familiarity with the silly things that can happen with spokes and wheels. I have wondered if this particular one is just a lemon, given how quickly the spokes started to loosen (a month or so after I got the bike).

Actually, scrottie discovered quite recently that he's cracked a rim, which seems like a somewhat unusual failure until you consider that he also tends to be pretty hard on his equipment. Ach, wheels.

This is the shop the built the bike, btw, in case I haven't noted this before:

http://www.rodcycle.com/

[randomdreams.livejournal.com]

I've seen rim failures from overtightened spokes (and, sometimes, heavy loading) but I've also seen them for defective rims. Weinmann rims in the '80's had a horrible problem with cracking radially between the spoke holes, and it was simply a problem with their extrusion process.

[randomdreams.livejournal.com]

by the way, the general opinion (and I don't know how accurate this is) is that hubs should have the spoke holes slightly chamfered and the outer flange surface should be canted in towards the center of the wheel at about 6 degrees, to try to minimize the spoke bend, and the pulling spokes on the rear wheel, especially on the sprocket side, should be on the outside. (That one's subject to argument, because the outside sprocket side spokes are a: the highest tension, b: take the most strain during pedaling, and c: are the spokes that get damaged if you ever overshift off the large cog, so an argument is sometimes made that the push spokes should be on the outside as they'll last way longer after an overshift.)

broken spokes

[jim bronson (from livejournal.com)]

I weigh 270+ and I don't break spokes, although I have trashed a couple of rear hubs. I ride 32h wheels on my Rivendell, just like you.

Did they use straight gauge 1.8 (15ga) spokes when they build your wheel? Maybe the spoke tension is just too high? Or maybe they used 2.0/1.5/2.0 (14/16/14 ga) butted spokes and they're just too fragile for loaded Randonneuring?

You'll know if you have straight gauge or butted spokes just by pinching the spoke between two fingers and then running those two fingers up and down the length of the spoke. If it's a butted spoke, you'll be able to feel where the width of the spoke transitions from one width to another.

You can get a cheap pair of calipers to measure the spoke at HomeDepot, I paid $7 for mine. They have expensive fancy ones, even electronic, but my cheap manual calipers work fine.

Re: broken spokes

[rebeccmeister.livejournal.com]

Thanks for the tip on how to check straight gauge vs. butted. I suspect they're straight gauge. And for the reality check on whether it's my fault or the wheel's fault. :-)

Overall, the spoke tension has been too low - spokes have periodically worked loose and I've had to re-tighten them more often than seems reasonable. It could be that I started a cascade of problems by over-stressing the wheel when hauling compost (I don't know the total weight, but enough to fill a large bike trailer), and then the non-driveside spoke tension got wacky and never got fixed.

Fun times. All in all, I am just hoping to get things straightened out before the 600k so I can focus on the bike-riding part instead of the mechanical-fixing part.