Advertise on Bikeforums.net



User Tag List

Results 1 to 17 of 17
  1. #1
    Road cyclist
    Join Date
    Aug 2009
    Location
    Ireland
    My Bikes
    Trek 400, Raleigh Panasonic, Barracuda Magma
    Posts
    29
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

    Spoke Length variance allowed?

    Hi,

    Having built a few 3 cross wheels I wanted to try something different just for the fun of it.

    I've got a pretty sweet price on some 290mm spokes, the front wheel is 32h, want to lace it 2 leading 2 trailing, and the rear is 36h, want to lead it 3 leadng 3 trailing.

    Now, i've calculated the front to need 290.6mm spokes, so they'll be fine, but the back requires 292.6mm.

    This on either side add's up to 5mm of a difference.

    Will I be able to use 290mm spokes on the 36h wheel that requires 292.6mm? I'm using standard. 12mm nipples that protrude roughly 6.5mm out of the rim.

    The spokes are threaded for around 10mm at the end of the spoke.

    Hope this is enough info,
    Cheers,
    Paul

  2. #2
    headtube. zzyzx_xyzzy's Avatar
    Join Date
    Sep 2008
    Posts
    804
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    If it's a really good deal on 290 spokes it could work if you get 14mm nipples for the rear wheel. Otherwise you might not engage enough of the threads inside the nipple.

  3. #3
    Senior Member
    Join Date
    Feb 2005
    Location
    Oklahoma
    My Bikes
    Trek 5500, Colnago C-50
    Posts
    9,087
    Mentioned
    2 Post(s)
    Tagged
    0 Thread(s)
    I think they'll be fine.

  4. #4
    cab horn
    Join Date
    Jun 2004
    Location
    Toronto
    My Bikes
    1987 Bianchi Campione
    Posts
    28,295
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by Pir0 View Post
    Hi,

    Having built a few 3 cross wheels I wanted to try something different just for the fun of it.

    I've got a pretty sweet price on some 290mm spokes, the front wheel is 32h, want to lace it 2 leading 2 trailing, and the rear is 36h, want to lead it 3 leadng 3 trailing.

    Now, i've calculated the front to need 290.6mm spokes, so they'll be fine, but the back requires 292.6mm.

    This on either side add's up to 5mm of a difference.

    Will I be able to use 290mm spokes on the 36h wheel that requires 292.6mm? I'm using standard. 12mm nipples that protrude roughly 6.5mm out of the rim.

    The spokes are threaded for around 10mm at the end of the spoke.

    Hope this is enough info,
    Cheers,
    Paul
    No.

    If you've measured everything right, it's +/- 1mm tolerance. 290's will not work for a 292.6 (293). You will have little to zero tension on the rear, left side. Even if you tried to compensate by overtensioning the rear drive side. Do not do this.
    Mes compaingnons cui j'amoie et cui j'aim,... Me di, chanson.

  5. #5
    Road cyclist
    Join Date
    Aug 2009
    Location
    Ireland
    My Bikes
    Trek 400, Raleigh Panasonic, Barracuda Magma
    Posts
    29
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    I forgot to mention the rear hub is a single speed hub with equal diameter flanges. The same distance from the centre.

    I understand you need 2 different sized spokes for freewheel hubs and freehubs. But this is a fixed fixed hub, so it's symetrical.

    Reckon it'd be alright now?

  6. #6
    Road cyclist
    Join Date
    Aug 2009
    Location
    Ireland
    My Bikes
    Trek 400, Raleigh Panasonic, Barracuda Magma
    Posts
    29
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by Pir0 View Post
    I forgot to mention the rear hub is a single speed hub with equal diameter flanges. The same distance from the centre.

    I understand you need 2 different sized spokes for freewheel hubs and freehubs. But this is a fixed fixed hub, so it's symetrical.

    Reckon it'd be alright now?
    Here's a pic I made as I do with all the wheelbuilds I do to keep me right,


    (Btw the flange diameter in this IS measured centre to centre of opposite holes, not to the edge as pictured, that's just a quick template I made.)
    The rim has an ERD of 608mm

  7. #7
    cab horn
    Join Date
    Jun 2004
    Location
    Toronto
    My Bikes
    1987 Bianchi Campione
    Posts
    28,295
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    There is no way that blue measurement is 135mm. It doesn't even include either cone/locknut on BOTH sides. That hub would fit on NO bike. And again, 290 will not work on a spoke length spec'ed for 293, regardless if it's dishless.
    Last edited by operator; 01-05-10 at 09:41 AM.
    Mes compaingnons cui j'amoie et cui j'aim,... Me di, chanson.

  8. #8
    nice idea, poor execution
    Join Date
    Oct 2009
    Location
    West Newton, MA
    Posts
    397
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    That's not the only thing wrong with that picture.
    Kevin Duffy, Harris Cyclery, West Newton, MA.
    blog.harriscyclery.com

  9. #9
    Road cyclist
    Join Date
    Aug 2009
    Location
    Ireland
    My Bikes
    Trek 400, Raleigh Panasonic, Barracuda Magma
    Posts
    29
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Regardless of the picture, the measurements I've taken are fine i made that in a hurry and clearly misplaced some of the lines.

    So on a dishless wheel with a symmetrical hub, 290mm spokes wont work with 12mm nipples, for a wheel i've calculated needs 292.6mm spokes? And there's no way around it other than to get 292mm or 293mm spokes?

    Is it better to round up to the nearest whole number than round down?

  10. #10
    Useful Idiot cincy_14's Avatar
    Join Date
    Jul 2006
    Location
    Butler, OH
    My Bikes
    Giant RS940, Schwinn Sports Tourer
    Posts
    25
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by Pir0 View Post
    Regardless of the picture, the measurements I've taken are fine i made that in a hurry and clearly misplaced some of the lines.

    So on a dishless wheel with a symmetrical hub, 290mm spokes wont work with 12mm nipples, for a wheel i've calculated needs 292.6mm spokes? And there's no way around it other than to get 292mm or 293mm spokes?

    Is it better to round up to the nearest whole number than round down?
    292 is the shortest length I would use on your rear wheel. Longer nipple will not help you, as I don't believe they have any longer threads.

    You can round up or down depending on your ERD measurement. When I use the manufacturer's ERD I usually round down and when I measure the ERD myself to the bottom of the nipple screwdriver slot I round up. Rounding down by 2.6mm is too much IMO.

  11. #11
    Senior Member
    Join Date
    Feb 2005
    Location
    Oklahoma
    My Bikes
    Trek 5500, Colnago C-50
    Posts
    9,087
    Mentioned
    2 Post(s)
    Tagged
    0 Thread(s)
    It's always better to round down to avoid running out of threads. This is more important on wheels on rear wheels with high driveside tension.

  12. #12
    Retro-Direct Fan TwoShort's Avatar
    Join Date
    Aug 2007
    Location
    Boulder, Colorado
    Posts
    160
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Generally, one would calculate the optimal length, then round to the nearest available spoke length. Depending upon the obscurity of your length requirement & spoke type & the extensiveness of your suppliers inventory, this will generally mean rounding by less than a mm, but sometimes more. 2mm off is about the maximum that would typically ever be required, and I 'd generally recommend against exceeding it.

    On the other hand, you'll probably be fine. They'll reach, but you'll have a bit less thread engagement than is optimal; slightly more chance of breaking a spoke. You're going 3-leading, 3-trailing, so obviously "optimal" is not the target.

    I have build very nice 3-cross wheels where I wouldn't have dreamed of being off by 2.6. I have also laced the cheapest spokes I could find to a beat-up coaster hub in the very 3&3 pattern you describe. I say, go for it.

  13. #13
    Senior Member
    Join Date
    Feb 2009
    Posts
    3,969
    Mentioned
    4 Post(s)
    Tagged
    0 Thread(s)
    You can do just fine with 3mm short. It just isn't the Sunday-go-to-meeting way to go.

  14. #14
    Senior Member mrrabbit's Avatar
    Join Date
    Dec 2007
    Location
    San Jose, California
    My Bikes
    2001 Tommasini Sintesi w/ Campagnolo Daytona 10 Speed
    Posts
    3,175
    Mentioned
    1 Post(s)
    Tagged
    0 Thread(s)
    Nope...wouldn't do it...don't use nipples as a spokes...nipple barrels will eventually break...unless you are certain that the spoke ends are getting into the rim a mm or so after final tension.

    Also if those spokes are DT or Ritchey...I wouldn't be surprised if they came out of the box measuring 289.5 mm...leftover stocks of DT and Ritchey spokes from the 80s and 90s still show up with spokes .5mm under the box labelled size.

    Check with a Park Tool or Wheelsmith spoke ruler...

    =8-)

  15. #15
    BeaverTerror Yan's Avatar
    Join Date
    Jan 2006
    Location
    Shanghai, China
    My Bikes
    2013 True North custom touring; 2009 Unicycle.com Club Uni; 1989 Miele Tivoli; 1979 Colnago Sport
    Posts
    1,559
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    This link says that spokes for 3 leading 3 trailing wheels should be 1-2 mm longer than required, because the extra lacing in this pattern takes up a bit of length. I think 2.5mm short would normally be fine, but maybe not in this case. I have never built a wheel in this pattern.
    Yan

    2013 True North custom touring; 2010 Novara Randonee; 2009 Unicycle.com Club 24"; 1989 Miele Tivoli; 1979 Colnago Sport

  16. #16
    Road cyclist
    Join Date
    Aug 2009
    Location
    Ireland
    My Bikes
    Trek 400, Raleigh Panasonic, Barracuda Magma
    Posts
    29
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Thanks a lot for the advice guys. 290mm is a pretty sure length to buy though, I've used them before and now again, so i'm sure i'll use them in future.

    I think I would need longer spokes for the rear after reading some, it just means I'll probably end up buying some cheapo spokes cut to length instead of the double butted oens I wanted, but then again, as I said, I'm only doing this for a bit of fun and for a change. As for 3leading 3 trailing needing longer spokes, Iknow quite a few guys who have bought standard 3 cross cheap wheels and re laced them for the fun of it with no problems due to spoke length.

    As was said, i'm not going for the best wheel I can build I just want a little project to work at over the break. I think I'll still get the 290mm spokes for the front and see what I can get in the mean time for the back and keep an eye out for some better spokes, and if they're cheap enough get them and relace the whee, no harm done.



    Again, thanks a lot for the info guys, much appreciated,
    Cheers,
    Paul

  17. #17
    Senior Member
    Join Date
    Mar 2008
    Posts
    4,178
    Mentioned
    1 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by Pir0 View Post
    ... 290mm spokes wont work with 12mm nipples, for a wheel i've calculated needs 292.6mm spokes? And there's no way around it other than to get 292mm or 293mm spokes?
    I might try that build if it was parts that I had on hand, but I wouldn't buy parts with such poor odds of fitting. You're basically trading out all your margin of error in the first round.

    I 've had no problems compensating for shorter spokes with longer nipples though.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •