Andy_K 

My rear derailleur exploded (pic) in a cyclocross race this weekend, and (whether this is cause or effect, I can only guess) I ended up with a couple of bent spokes and an out-of-true wheel. The bent spokes (which also have a nick or two) lost a lot of tension, but the wobble in the wheel was only enough to get it to rub the brakes. Restoring tension to the bent spokes, the bends straightened out a bit and the wobble became even less pronounced. It seems clear that I could true the wheel as is. (The wheel has 32 spokes, FWIW.)

Now, I know that the right thing to do is to replace the bent spokes. I'm not trying to be cheap. However, I'm wondering if it is reasonable to true the wheel as is now and put off the spoke replacement until the end of cross season, when the whole bike will be getting lots of TLC anyway. I'll only be using this wheels for racing, so there's no worry that I'll be stranded somewhere, and I'm crazy slow, so a DNF isn't a big deal.

So, what do you think? Is it reasonable to put this off?

Al1943

There's no way of knowing how long that wheel will hold together. So it's really up to you.
I'd be more concerned with you the derailleur got destroyed.

oldbobcat

If it was me, as long as I was truing a wheel I'd just as soon replace the damaged spokes, too.

peripatetic

The fact you were able to get the spokes back up to tension and that that sufficiently trued the wheel makes it likely the spokes themselves didn't suffer undue structural fatigue. That argues for being able to put off their replacements. Doesn't mean there's no risk. Seems the fact you had to "fix" stuff a bit is sufficient warning to you of the potential risk: It's your judgment whether you think the spokes were, in fact, damaged.

One thing you might do is to mark the specific spokes involved, then check their tension after every further race. Perhaps you'll figure out quickly that they're just no staying tensioned, which will be an indicator the problem needs addressing sooner rather than later.

Andy_K 

Well, I'm fairly certain that the derailleur hit the spokes. There was thick mud and assorted woodsy debris involved, so I'm not worried about the root cause of the derailleur getting in the spokes. I can feel some barbs as I run my fingers along the spokes. They're definitely worse off than they were before the incident. The biggest issue for me is when I'll have time to replace them.

When I do the replacement, do I need to worry about what's going on with the rim when I take them out? Like should I replace one before removing the other?

achoo

The problem will be the nicks in the spokes being starting points for cracks.

I wouldn't trust them for very long at all.

BCRider

Based on this occurance I wonder if a nice big, oversized even, spoke protector would not be a good idea. One big enough to deflect an errant derrailleur. Such a protector could be easily made from some thin clear stiff sheet plastic cut to a "donut" shape and then one cut straight in. Attach to the spokes with small tie wraps through small drilled holes in a number of spots with the joint at the cut overlapping so anything riding on the protector doesn't catch the lip. It may look dorky but if it avoids the same issue again it would be pukka racing gear and not a "dork disc"

doOde

bummer about the clogged up gear. spokes are pretty hardy fellows as long as you dont kink them. if the bend is gradual its fine. id imagine even if they are kinked they should hang tough til you hear that special "ping!".

in my experience you get spoke fatigue failure at the elbow and failure mid-spoke if it has corrosion damage which weakened it. you should be fine though.

davidad

If the spokes are nicked you should go ahead and replace them. The cuts act as a stress riser and the spoke will break there.

fietsbob

put on a spare wheel, rebuild the damaged one..
You do have a spare wheel set don't you, ?
if not a whole spare bike.. and a hoser helper, to clean the spare bike?

It's how races are won in Cross..

Andy_K 

I'm in no danger of winning a race anytime soon. I'm still working on cracking the top 75%.

I do have a spare bike, which I'll be using while the bent hanger on the damaged bike gets repaired. If I sideline this wheel, I won't have a spare. The backup wheels are Tiagra/Alex, but I guess I can race with those and use this one as the backup for a while. Mainly I didn't want to be without a wheel to use on the trainer before races. I don't know why I didn't think to use the damaged wheel for that. Sometimes my brain stalls for a while.