Are SAPIM J-bend spokes shorter than nominally identical DT ?
#1
Full Member
Thread Starter
Join Date: Jan 2020
Posts: 265
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 125 Post(s)
Liked 29 Times
in
24 Posts
Are SAPIM J-bend spokes shorter than nominally identical DT ?
Is it true that SAPIM measures their spokes from centre of the bend while DT from the inner edge? Shall I subtract 1mm from DT swiss calculator results when using SAPIM spokes?
#2
Senior member
Join Date: Oct 2004
Location: Oakville Ontario
Posts: 8,108
Mentioned: 25 Post(s)
Tagged: 0 Thread(s)
Quoted: 937 Post(s)
Liked 652 Times
in
367 Posts
Not sure where you got that from, but I have tons of both brands here and never found that to be true. Most of the time, I'm cutting spokes to length anyway, but for those times I'm not, the Sapims always measure accurately out of the bag on my spoke ruler.
#3
working on my sandal tan
Join Date: Aug 2011
Location: CID
Posts: 22,625
Bikes: 1991 Bianchi Eros, 1964 Armstrong, 1988 Diamondback Ascent, 1988 Bianchi Premio, 1987 Bianchi Sport SX, 1980s Raleigh mixte (hers), All-City Space Horse (hers)
Mentioned: 98 Post(s)
Tagged: 0 Thread(s)
Quoted: 3868 Post(s)
Liked 2,560 Times
in
1,574 Posts
I've never heard that either. I ordered Sapim spokes from Danscomp a few years ago for a project, and the spoke ends landed exactly where I expected them to.
@avrilboazmoss, I have a radical idea for you: have you considered emailing the company to find out?
@avrilboazmoss, I have a radical idea for you: have you considered emailing the company to find out?
#5
Full Member
Thread Starter
Join Date: Jan 2020
Posts: 265
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 125 Post(s)
Liked 29 Times
in
24 Posts
Nothing authoritative, just a random post withing rounding up/down discussion in 2016 on mtbr forum:
Just to toss more confusion into your woes, perhaps you should find out how spokes mfgs measure their lengths. I know DT DOES NOT measure from center of the J-bent section to the tip of the threads. They use inside to tip length, so if you use 2mm, you should add 1mm. Sapim, on the other hand, DOES measure center to tip and their labeled lengths are exactly 1mm short when you lay it on a Park spoke ruler (what I used for the DT also).
#6
Senior Member
Join Date: Feb 2012
Location: Rochester, NY
Posts: 18,003
Bikes: Stewart S&S coupled sport tourer, Stewart Sunday light, Stewart Commuting, Stewart Touring, Co Motion Tandem, Stewart 3-Spd, Stewart Track, Fuji Finest, Mongoose Tomac ATB, GT Bravado ATB, JCP Folder, Stewart 650B ATB
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 4172 Post(s)
Liked 3,791 Times
in
2,270 Posts
One hopes that 1mm of spoke length change won't ruin your wheels.
I've cut hundreds of spokes on a few different Phil machines and assume on a .5mm variance is resulting length. If I need a closer length tolerance I have cut/thread the spoke long and ground to the length and run the spoke through the cutter/threaded to clean up and resize the threads. Andy
I've cut hundreds of spokes on a few different Phil machines and assume on a .5mm variance is resulting length. If I need a closer length tolerance I have cut/thread the spoke long and ground to the length and run the spoke through the cutter/threaded to clean up and resize the threads. Andy
__________________
AndrewRStewart
AndrewRStewart
#7
Senior Member
Join Date: Jan 2013
Location: Llano Estacado
Posts: 3,702
Bikes: old clunker
Mentioned: 13 Post(s)
Tagged: 0 Thread(s)
Quoted: 684 Post(s)
Likes: 0
Liked 104 Times
in
82 Posts
Nothing authoritative, just a random post withing rounding up/down discussion in 2016 on mtbr forum:
Just to toss more confusion into your woes, perhaps you should find out how spokes mfgs measure their lengths. I know DT DOES NOT measure from center of the J-bent section to the tip of the threads. They use inside to tip length, so if you use 2mm, you should add 1mm. Sapim, on the other hand, DOES measure center to tip and their labeled lengths are exactly 1mm short when you lay it on a Park spoke ruler (what I used for the DT also).
#8
Senior member
Join Date: Oct 2004
Location: Oakville Ontario
Posts: 8,108
Mentioned: 25 Post(s)
Tagged: 0 Thread(s)
Quoted: 937 Post(s)
Liked 652 Times
in
367 Posts
OK, how about some actual confirmation. Here I have a spoke taken from a bag of Sapim Race spokes marked as 268mm
And a DT Swiss
As near as my old eyes can tell, the Sapim is pretty much dead on 268 whereas the DT is about 1/2 mm short. I consider that within tolerance.
And a DT Swiss
As near as my old eyes can tell, the Sapim is pretty much dead on 268 whereas the DT is about 1/2 mm short. I consider that within tolerance.
Likes For Dan Burkhart:
#9
Senior Member
Join Date: Jan 2017
Posts: 1,064
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 350 Post(s)
Likes: 0
Liked 122 Times
in
90 Posts
For the last wheels that I built, I accidentally measured from the end of the bend instead of the middle of the bend. This made me order 1mm longer sapim spokes. Then, the spokes I received had up to 1.5mm of differences in length. And the holes on the flange can be a little off center, I'd say 0.5mm.
So the result was most spoke tips ending 1mm above the nipple slot, but a few were at the top of the nipple head. Sapim 12 and 14mm nipples can have the spoke tips bottom out when they are around 0.5mm above the nipple head. But there were 2 spokes that went a further 1mm, so the tip was 1.5mm to 2mm above the spoke head. I simply turn the spoke 2 or 3 revolutions further after bottoming out. I don't think it's a problem and may help with retention.
So the result was most spoke tips ending 1mm above the nipple slot, but a few were at the top of the nipple head. Sapim 12 and 14mm nipples can have the spoke tips bottom out when they are around 0.5mm above the nipple head. But there were 2 spokes that went a further 1mm, so the tip was 1.5mm to 2mm above the spoke head. I simply turn the spoke 2 or 3 revolutions further after bottoming out. I don't think it's a problem and may help with retention.
Likes For tomtomtom123:
#10
Senior Member
Join Date: Dec 2007
Location: San Jose, California
Posts: 3,504
Bikes: 2001 Tommasini Sintesi w/ Campagnolo Daytona 10 Speed
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 145 Post(s)
Likes: 0
Liked 35 Times
in
30 Posts
DT Swiss measures from center to end
All others that I know of measure from inside to end.
For 14g (2.0mm) spokes - it is about a .5mm diff.
So it's basically something only to be concerned with with DT Swiss spokes AS-IS from a box.
=8-)
All others that I know of measure from inside to end.
For 14g (2.0mm) spokes - it is about a .5mm diff.
So it's basically something only to be concerned with with DT Swiss spokes AS-IS from a box.
=8-)
__________________
5000+ wheels built since 1984...
Disclaimer:
1. I do not claim to be an expert in bicycle mechanics despite my experience.
2. I like anyone will comment in other areas.
3. I do not own the preexisting concepts of DISH and ERD.
4. I will provide information as I always have to others that I believe will help them protect themselves from unscrupulous mechanics.
5. My all time favorite book is:
Kahane, Howard. Logic and Contemporary Rhetoric: The Use of Reason in Everyday Life
5000+ wheels built since 1984...
Disclaimer:
1. I do not claim to be an expert in bicycle mechanics despite my experience.
2. I like anyone will comment in other areas.
3. I do not own the preexisting concepts of DISH and ERD.
4. I will provide information as I always have to others that I believe will help them protect themselves from unscrupulous mechanics.
5. My all time favorite book is:
Kahane, Howard. Logic and Contemporary Rhetoric: The Use of Reason in Everyday Life