Looking to have my wheel re-built but change from a Mavic XC717 to XM321.

I’ll keep the Pro II hub.

Using https://leonard.io/edd/ spoke calculator, I can see the info says that

XC717
ERD: 541mm
OSB: 0mm

XM321
ERD: 538.5
OSB: 0mm

Whilst I have no idea what that means, am I likely to need new spokes? How much leeway is there in spoke length?

I remember years ago, being told that re-using spokes isn’t a good idea. They become weakened as they go from tensioned to un-tensioned and then re-tensioned. Any truth in that?

I can’t believe the price of 32 spokes is so close to that of the rim. Yes, I know I’m being tight…

Thanks a lot

Depends who is rebuilding the wheel! Not sure every professional wheelbuilder or shop will want to use used spokes but if its a new rim rather than a crash/pringled wheel repair then its a pretty normal job.

If the wheel was sound before you unlace it then fine to reuse spokes imho. But be sure to undo the tension in the spokes evenly, ie go round the wheel a few times slacking off each spoke just a turn at a time rather than just undoing each one completely. In fact if you are keeping the hub and swapping the rim its a case of then taping the new rim to the old one (valve holes lined up) to swap them across one by one. (When i do it like this i like to dunk each nipple in oil as I go to help get a good tension -wheelpro book reccommends light oil for this, but if you are building from scratch its tidier to use a cotton bud to wipe inside of spoke hole and dip the ends of the spokes in oil -this way is a bit messy and requires much cleaning a couple of layers of electrical tape afterwards to stop excess oil seeping through cloth rim tape and eating your inner tubes.)
Re length: this is only a little over a mm in terms of distance from the hub plus spokes go into hub at an angle so potentially not a great change. Have a look inside the current rim as it is built now, and see how close the tops of the spokes are to the top (slotted bit inside the rim) of the nipples. You are going to see each spoke go further into the nipple but not by masses with that difference in ERD so if they aren’t poking out the tops of the nipples already you should be fine.
And get yourself a good wheelbuilding guide and take your time!

Thanks Julian.

I’m not doing the building. An LBS is. I only know one other person who’s had their wheels built there and they’re happy after about 12 months. Any work I’ve had done at the shop has been top notch.

I’m happy to fettle but £20 for a build is worth every penny IMO. Especially as I’m at the Jeremy Clarkson (as opposed to James May) end of the mechanical-competence spectrum.

I was in the shop this morning for a different reason but got an itemised quote for rim, spokes and labour. It was only sat here procrastinating, I wondered if the spokes from my current wheel can be re-used.

The current wheel isn’t completely pringled but has a distinctive wobble and is as trued as the the nipples / spoke thread will allow.

I’ll have a look to see how much spoke is in / out of the nipple when I get home.

Thanks for the reply.

quick look at the calculator you linked would suggest you can keep the spokes.

Ask the wheel builder though – much better to measure components than use online calculator – some of the numbers on there are wrong from experience.

None I know will rebuild using old spokes as it can lead to complaints down the line if spokes snap due to previous build.

If ive built the wheel and I know the history then i’ll happily rim swap.

Ask your builder- there’s 2 questions, can they and will they and only they can answer both.

When doing an identical rim swap I’ve re-used* – tape the new rim to the old one loosed them all off and transfer one by one to new rim. Pretty sure most pros say new spokes, you might well be able to re-use (edd says 260/262 for your 717 and 259/261 for the 321) if you build it yourself.

*but not on a wheel I’m likely to batter the hell out of

I’ve rerimmed 3 wheels using old DT spokes, no problems. El cheapo spokes may be a different matter.

If you start a wheel build with spokes that are 2mm the wrong side of what you need it is not ideal. 1mm out may be incrementally less of a problem.

If I was the wheel builder taking on the job and you were insisting on using old spokes that were the wrong length, I think I might tell you, “No thank you Sir, I don’t need that job, and neither do you.”

You may get away with it though.

Unscrewing old spokes takes time which is probably why lots of places don’t want to bother – they just chop them if doing a new rim and spokes. In the rim abrasion days before discs, we’ve had hubs and spokes which were used for multiple rims.

Why not swap the rim over yourself as described above? That bit is easy but time consuming. You then have the option to finish the job yourself or take it to a shop to get tensioned up.

If re-using an old hub and spokes, I’d always do the tape together new / old rim swap. Old spokes will be slightly bent near the head and hub flanges indented so everything is generally bedded into each other. Handing them a pile of old spokes is certain for them to end up in new locations.

If just re-using the hub, I’d ask them to ensure new spokes get aligned in the same directions as old spokes – I’ve had hub flanges fracture very quickly after a rebuild where spokes were pulling flange in “new” directions (so again, the tape 2 rims together options makes this much easier).

I’ve just got a message from the builder.

He said, he’ll do it but the cost of the build increases a little. I guess to offset lost profit on spokes; fair enough. However, you lose the “one free truing / tightening” he gives other customers.

I think I’ll suck it up and get new spokes. Especially as I’m probably going to batter the hell outta this rim.

An XM321 obviously isn’t a lightweight wheel and the LBS owner is trying to persuade me with a deal on front and rear wheels with EX325s.

You can probably use the same spokes as the required length will change by just over 1mm. It all depends on which spokes the original builder chose for the build. If they chose longer than the ideal length, then you may run out of thread before getting up to tension. If you look into the rim, can you see the spoke ends poking out of the tops of the nipples?