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echappist
12-23-2015, 12:31 PM
So my front wheel is pretty much toast as the brake track has been worn quite thin. My wheel is a Kinlin XR-300 laced to a White Industry H2 using 24 x 274 cm Sapim CX-Ray spokes, and as luck would have it, the rim i'm interested in (Kinlin 31W) will use spokes of the same length. My wheel has probably 25-30k miles on them, and my question is if the spokes could be used?

Also, is there a rule of thumb when it comes to reusing spokes?

Thanks!

Black Dog
12-23-2015, 12:40 PM
If you are just doing a re-rim then go for it. The spokes will be fine. If the nipples are alloy then you may want to replace them. As for rules of thumb, there is not much out there. High millage rear wheel drive side spokes might fall in the 'replace' category. I have a set of wheels that are on their 3rd rim with more than 60000km on them, original spokes.

crashnburn
12-23-2015, 12:43 PM
From Roger Musson's book:

"If you intend to reuse the spokes you should try and keep the spokes segregated. The spoke elbows will have taken a particular bend and ideally they need replacing in the hub the same way when building the new wheel. Doing this prevents putting new bends in the elbows which can lead to possible fatigue issues. For a rear wheel there will be four sets: inside (drive), inside (non drive), outside (drive) and outside (non drive). A standard front wheel will have two sets: inside and outside and a disc front wheel four sets. If you get them all mixed up then providing they were good quality spokes it shouldnšĘš matter too much, but get into the habit of keeping them separate.
The following sections show how to replace a rim or hub using techniques for re using the previous spokes."

In another section:

"If you are reusing old spokes and placed them in the hub the same way they were removed from the previous hub they will already have the correct alignment and will not require any modifications but it does no harm to check and re align if necessary.
Once aligned, the spokes will lose a little tension."

echelon_john
12-23-2015, 12:55 PM
Rule of Thumb: Don't.

AngryScientist
12-23-2015, 01:00 PM
i donno about rules of thumb, but i do know that building a wheel is kind of a pain in the ass, and i also know that 30k miles is kind of a lot of miles for a wheel, so if i were going to build a new wheel anyway, i'd probably just spring for some new spokes and KNOW they are good. IMO.

bfd
12-23-2015, 01:02 PM
So my front wheel is pretty much toast as the brake track has been worn quite thin. My wheel is a Kinlin XR-300 laced to a White Industry H2 using 24 x 274 cm Sapim CX-Ray spokes, and as luck would have it, the rim i'm interested in (Kinlin 31W) will use spokes of the same length. My wheel has probably 25-30k miles on them, and my question is if the spokes could be used?

Also, is there a rule of thumb when it comes to reusing spokes?

Thanks!

Jobst Brandt had a FAQ on reusing spokes:

There is no reason why you should not reuse the spokes of your relatively new wheel. The reason a bike shop would not choose to do this is that they do not know the history of your spokes and do not want to risk their work on unknown materials. If you are satisfied that the spokes are good quality, you should definitely use them for you new wheel. The spokes should, however, not be removed from the hub, because they have all taken a set peculiar to their location, be that inside or outside spokes. The elbows of outside spokes, for instance, have an acute angle while the inside spokes are obtuse.

There are a few restrictions to this method, such as that new rim must have the same effective diameter as the old, or the spokes will be the wrong length. The rim should also be the same "handedness" so that the rim holes are offset in the correct direction. This is not a fatal problem, because you can advance the rim one hole so that there is a match. The only problem is that the stem will not fall between parallel spokes as it should for pumping convenience.

Take a cotton swab and dab a little oil in each spoke socket of the new rim before you begin. Hold the rims side by side so that the stem holes are aligned and note whether the rim holes are staggered in the same way. If not, line the rim up so they are. Then unscrew one spoke at a time, put a wipe of oil on the threads and engage it in the new rim. When they are all in the new rim you proceed as you would truing any wheel. Details of this are in a good book on building wheels.

The reason you can reuse spokes is that their failure mode is fatigue. There is no other way of causing a fatigue failure than to ride many thousand miles (if your wheel is properly built). A crash does not induce fatigue, nor does it even raise tension in spokes unless you get a pedal between them. Unless a spoke has a kink that cannot be straightened by hand, it can be reused.


http://sheldonbrown.com/brandt/reusing-spokes.html

Good Luck!

echappist
12-23-2015, 01:18 PM
thanks everyone! i guess i'll bite the bullet and order the new spokes. That last part re: fatigue mode really caught my attention.

Black Dog
12-23-2015, 01:42 PM
thanks everyone! i guess i'll bite the bullet and order the new spokes. That last part re: fatigue mode really caught my attention.

CX-ray spokes are very good and have great fatigue resistance. Like the, arguably, the worlds leading expert on bicycle wheel said, if you are just replacing the rim then you should be fine especially on a front wheel. Replacing the rim does not stress the spokes or shorten their life.

echappist
12-23-2015, 01:54 PM
i guess the difference here is that i'm replacing using a different rim, albeit one that is very similar to what i currently have. I'll mull this over a bit more.

Also it's strange that the XR-300 is listed with an ERD of 577mm, which is less than that of the XR-31T at 580mm. :confused:

FlashUNC
12-23-2015, 01:57 PM
New rim, new spokes. Especially if its a different rim.

Cheap insurance imo.

vqdriver
12-23-2015, 02:13 PM
Just replace them along with the nipples.
Probably won't fail in dramatic fashion. Maybe a failure here and there or odd truing issues. Annoying

beeatnik
12-23-2015, 02:15 PM
i guess the difference here is that i'm replacing using a different rim, albeit one that is very similar to what i currently have. I'll mull this over a bit more.

Also it's strange that the XR-300 is listed with an ERD of 577mm, which is less than that of the XR-31T at 580mm. :confused:

If the rim has the same ERD and offset, you're fine. It doesn't have to be the same model. Now if you were using a different hub (with same geo or not), that would be an issue. At least that's what I'm reading from Black Dog and JB.

unterhausen
12-23-2015, 02:18 PM
I used to swap rims all the time. Transfer one spoke at a time. I can never talk myself into it nowadays.

With 30k miles, those spokes don't owe you anything, swap them out

bicycletricycle
12-23-2015, 02:30 PM
Re rim a wheel, sure.

Anything else, nope

redir
12-23-2015, 02:36 PM
I've built wheels with reused spokes in a similar manor on several occasions with no issues but as others mentioned with that kind of milage on them jsut start over.

Curve_in
12-23-2015, 02:36 PM
In my shop days, we'd always cut out the old spokes and start fresh. That way we were sure of the condition of all the spokes and nappies. If it was my personal wheel, I'd reuse front spokes but for the rear, it would depend on the condition of the spokes.

Sent from my SM-G920T using Tapatalk

Pastashop
12-23-2015, 04:46 PM
What crashnburn wrote / quoted. If they've gone for 30k miles without issues, they're pretty well stress-relieved and should work just fine, especially if the new rim is identical and the riding scenario doesn't change from what you did before. (Edit (due to brain fart): Steel DOES have a natural fatigue limit, so as long as their yield strength / that stress limit value hasn't been exceeded, they're good to go more Mike's (stress cycles). Read more here:

http://www.bssa.org.uk/topics.php?article=104

"Stainless steels exhibit a 'fatigue limit' or 'endurance limit' during cyclic stressing. This means that there is a stress level, below which fatigue failure should not occur. This is determined from a series of fatigue tests, run to failure at various stress levels.
The fatigue stress limit is reached when failure does not occur after a million (106) or 10 million (107) cycles.)"

fiamme red
12-23-2015, 05:51 PM
I've dented rims and got the same rims as replacements, and reused the spokes. No problems at all.

HenryA
12-23-2015, 11:08 PM
I cheaped out on my last rear wheel re-build by not using new spokes and after a few months started popping spokes. Over a few months it seemed I had to replace a spoke every 4 or 5 rides. I finally replaced the spokes and the breakage stopped.

One thing I did wrong was that the spokes got mixed up and not replaced in their original positions. I'll not do that again. I probably would replace a rim using the old spokes only if I kept the spokes in the same positions.

oldpotatoe
12-24-2015, 05:44 AM
So my front wheel is pretty much toast as the brake track has been worn quite thin. My wheel is a Kinlin XR-300 laced to a White Industry H2 using 24 x 274 cm Sapim CX-Ray spokes, and as luck would have it, the rim i'm interested in (Kinlin 31W) will use spokes of the same length. My wheel has probably 25-30k miles on them, and my question is if the spokes could be used?

Also, is there a rule of thumb when it comes to reusing spokes?

Thanks!

No rule of thumb, no rules at all sometimes but I'd say re-use them as long as the wheel hasn't been wacked, with the resulting goofy(and sometimes high) tension. I re-use all the time for same rim builds BUT I always replace the nipples. Particularly these very pricy spokes. Tape new rim to old, de-tension, move one spoke over at a time. That way they are in the same orientation at the hub.