jonTu

I'm about to re-build a wheel and am wondering if anyone can offer their experiences with re-using spokes. This wheel has a nice dent in the rim following a crash, but is only a year old with about ~3k miles on it. There was no visible damage to the spokes themselves. I'm wondering if replacing the spokes as well as the rim when I rebuild it would be a prudent measure to ensure the longevity of my rebuilt wheel, or a complete waste of $40. The spokes are nothing too exotic, DT Champions drive side and Revolutions non-drive, brass nipples all around. I'd appreciate any feedback.

urbanknight

I personally don't reuse spokes because detensioning them and retensioning them just seems like added stress. I don't think it's unsafe, however. It's just that I imagine the wheel will go out of true more frequently. If you do reuse the spokes, tape the new rim to the old rim and switch the spokes over without unlacing.

satanas

If *you* are going to rebuild the wheel yourself and you will use *exactly* the same type of rim then the spokes should be fine. I wouldn't remove them from the hub as doing so will mean that the bend at the elbow will be incorrect unless they go back in exactly the same orientation. Be careful to use a good fitting nipple key or you may round the nipples when undoing them. However, if you're planning on using a different rim, you may as well just save yourself the hassle and cut them out unless you are prepared to be frustrated when the spokes aren't quite close enough to the right size to work.

Do not expect a shop to re-use spokes; it is much more cost-effective to cut them out and use new ones, and doing this solves any potential problems with incorrect length, fatigue or damage as well.

jonTu

I'm inclined to replace the spokes as well, especially the Revolutions. But taping the rims together sounds like a really smart technique for replacing a rim. I've never thought to do that before, thanks for the tip!

urbanknight

Satanas is right, too, only reuse the spokes if you're using the same model rim (or at least one with the EXACT same ERD).

melville

Your exact situation (newish parts) is exactly when this technique should be used. I had a friend in Seattle who got three, maybe four months tops out of a Mavic M231 before he wore (wet braking) through the sidewalls. IIRC, he went at least two years (six ? builds) moving the spokes over from old to new. His Thursday night pre-race check was to inflate the tires to 100 psi and if the rim blew out, he had a couple days to get a new one together.

Good luck!

K6-III

If the ERD is the same, it is a safe bet to reuse your spokes.

Bill Kapaun

Not a wheel builder, but I wonder if the wheel had a big dent from a crash, couldn't a couple spokes have been "stretched"?
I'm wondering about tensioning issues.

urbanknight

Most likely not. If the rim got dented by hitting something, it compressed the rim, which would just relieve tension on the spoke. It could bend the spoke if dramatic enough, but even that can be stretched out of most spokes (although I would consider it the weak spoke of the wheel at that point).

jonTu

Yeah, the extent of the damage was a little dent in the sidewall. Enough to mess up the braking and make me nervous about the rim's ability to hold the bead of the tire, but not enough to laterally deform the rim below the braking surface. Had I actually taco'd the thing I don't think recycling spokes would be as promising a play.

Al1943

If you are building with an identical replacement rim the spokes should be fine. I don't know how much experience you have with Revolution spokes but I would plan to use pliers to hold the spokes so that they don't wind up under higher tension.

Al

urbanknight

^ Not pliers. Use post-its or something sticky to make flags pointing along the rim, then use them as a guide as to how far to back off the spoke to unwind. Also, be very careful on the tension on Revolutions. They have a narrower margin and too much tension will make your rim collapse (literally).

bikemeister

Darn - that is a really great method! I just learned something new! Thanks!

urbanknight

You'll never guess where I heard of it. Hint: it starts with the word bike and ends with the word forums I actually have never done it, but it seems simple enough.

BikingGrad80

That's what I did on my commuter last year. I replaced the rims with sun cr18's which were within a mm of the old rims. Worked well but some spokes started breaking on the rear wheel, mostly nondrive side oddly enough. I'd save the hastle and buy new spokes next time.

Michel Gagnon

If you are rebuilding the wheel, why not re-use the same spokes – providing they fit, obviously. Bike shops don't reuse them because they don't know their history and they have to guarantee their work. But you don't. So the worst that could happen is that you'll need to replace the spokes eventually.

Case in point.

My 520 came with Borntrager Farlaine (sp.) rims that weren't as resistant as our potholes. I went through the rear one in 7-8000 km. No dent. It's just that it was splitting apart...
So I replaced the rim with a Mavic A-719, re-using the hub and the spokes. In late 2006, I started having problems with the spokes. One broke by late 2006 and a few popped out in early 2007. That's when I decided to change the spokes. So at that time, I rebuilt the wheel with the same rim and same hub, but with new spokes. And by the way, I was slightly over 30 000 km.

dabac

Not odd at all. The most common spoke killer is fatigue, that is spoke changing from loaded to unloaded time after time.
On NDS spoke tension is lower, so the spoke can come pretty close to being unloaded(during certain circumstances) - so eventually it breaks due to the load changes it's seen. ON DS tension is higher, so change in load gets proportionally smaller and the spokes live longer.

dabac

+1

dabac

Unless you're using black spokes you can simply run a magic marker down the spoke. It'll leave a nice black line that you can use to monitor spoke wind-up. Once you're done a dash of the solvent of your choice on a rag is enough to clean the spokes right up again.

Too much tension will indeed collapse the rim, but that's all down to the tension and has nothing to do with the type of spokes you're using.

Sixty Fiver

This technique has been around for a very long time and I use it fairly often when I am doing a simple rim replacement on wheels with no other issues.

I just rebuilt the wheel for my 1948 Rudge and did a full rebuild as I was using a different 635 rim than the original (Canadian vs English sizing) and because of that went to a four cross / 40 instead of the 3 cross it had been re-laced to at some point in it's working life.

(The wheel would have most likely been laced 40/4 back in 1948).



It looks really great on the bike.

dabac

There's some leeway in ERD, an exact match isn't required and is mostly a question of build aestethics. But first one needs to know how the current wheel looks - are spokes flush with nipples, protruding a little, or already a little submerged?
If they're already protruding then going to a smaller ERD is a definite no-no, as that would bring a high risk of spokes bottoming out on the threads before reaching full tension.
But if current spokes are sitting flush there's no functional objections against using a rim with something like 5 mm bigger ERD.

Some adjustments can also be made by going to longer nipples, just make sure that the offset in ERD is big enough to keep the longer nipples from bottoming out.

Supposedly a little more risky would be to re-lace the wheel for a different cross.
For a hub with average flange height dropping/adding one cross would change the required spoke length with about 10 mm.
Established lore regarding hub re-use recommends that no of crosses and spoke orientation(inbound/outbound) should be maintained to prevent undue strain on the hub flanges - sounds reasonable, but then hub flange failures aren't particularly common.

jonTu

Yep, I found that to be a very good technique. I used a red grease pencil and just wiped off the marks when I was done.

urbanknight

Revolutions are just more sensative to this because they require a slightly higher tension, meaning you have to bring it closer to the max tension allowed on the rim, this narrowing the acceptable margin. I ran into that problem when using an Aerohead rim (fairly low max tension) with 24 revolution spokes (low count plus revolution required high tension). To make it more complicated, revolution spokes deflect more per tension so you need to use a tensionmeter with a guide for the narrow gauge to make sure you're not using too much tension. All I'm saying is be careful... from personal experience.

I like the marker idea!

True, you could probably be 1-2mm off and not have a problem. I was just saying that 1mm is 1mm in ERD, unlike center-to-flange which barely affects spoke length at all.