Spoke length 2mm di...
 

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[Closed] Spoke length 2mm difference important?

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my wheel specifies 287mm and 289mm non drive and drive side

is the 2 mm difference likely to be critical? and if I can get away with one length which one to go for? thanks

(Mavic wheels btw)


 
Posted : 16/03/2020 7:41 pm
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If probably build that with a box a 288mm

Or are they some sort of special spoke in limited sizes? If so, buy enough if each.


 
Posted : 16/03/2020 7:43 pm
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If probably build that with a box a 288mm

You can't, it's a Mavic wheelset with proprietary spokes.


 
Posted : 16/03/2020 7:44 pm
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yes - mavic wheel. Never had poncy wheels before, now I know why. They only sell spares in half wheel sets at about £35 a side - I need a drive side one but reckon I should have spares for every eventuality, but don't want to buy 2 sets, so wondering if I can get away with one length


 
Posted : 16/03/2020 7:48 pm
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eBay some of what you buy to recoup the cost


 
Posted : 17/03/2020 8:32 am
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Maybe ask an wheelbuilder if they could roll some threads and shorten a few of them? Dunno if thye're a standard thread though.

I'm guessing if they're custom made for mavic there probably isn't a whole lot of extra thread, so I'd be inclined to go with the short ones and risk the nipples cracking. Do you have the snapped one to hand, does it look like it could have been wound down another ~5 turns or wound out 2mm without an issue?


 
Posted : 17/03/2020 11:13 am
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Thanks spooky / really useful

I have experimented and managed to wind on (ie shorten the spoke) by 4 mm before the nipple wouldn’t turn any more. There’s 14mm of thread on the spoke, and about 1.5mm of unthreaded spoke inside the nipple

So I think this is telling me I could use the longer ones okay?? I may need to sit down and draw it to figure it out!


 
Posted : 17/03/2020 4:14 pm
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Probably, too long is fine unless it's so long it pokes into the tube and/or you run out of thread (standard thread pitch is 56tpi, so 4 turns is ~2mm).

Too short is OK too (within reason) as the brass has a lower modulus than the steel, so when you pull on the thread all the load is taken by the first few threads anyway. Nipples apparently* are more likely to crack if the spoke doesn't extend past the rim.

In a pinch I've built wheels with whatever random spokes I had leftover and just make up the difference in length with longer and shorter nipples. According to the DT calculator you can get away with 1mm shorter per 2mm of nipple (i.e. a 287mm spoke +16mm nipple or 289mm spoke +12mm nipple).

*i don't doubt it, but it's not happened to me


 
Posted : 17/03/2020 4:40 pm
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It’s a pretty deep rim so nipple is nowhere near the rim tape - thanks


 
Posted : 17/03/2020 4:48 pm
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Nipple washers could be used to take up some of the excess on the long ones. Although from your description of sounds like it might not be necessary.


 
Posted : 17/03/2020 4:54 pm
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or can you trim a couple of mm off the end of the long ones if needed?


 
Posted : 17/03/2020 9:49 pm

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