mrblue

Hello,

I have a set of wheels and I need to replace one spoke. The original spokes are straight pull, non-aero and double butted (2.0/1.7/2.0). I cannot find this particular spoke anywhere. Would there be any deleterious effects if I were to use a 2.0/1.8/2.0 spoke?

Thanks!

Bill Kapaun

I think Wheelsmith makes a 2.0-1.7-2.0.
Example-
https://www.treefortbikes.com/Wheels...yABEgJQq_D_BwE

I currently have a single 2.0 spoke on my R wheel to go with 15 2.0-1.8-2.0 spokes.
Some day when I order spokes for a wheel AND remember THAT spoke........it's been 2-3 years now.

pdlamb

No big deal. Unless it's a different color.

cpach

Not a big deal, but 2.0/1.7/2.0 is usually Wheelsmith and you could probably find an exact replacement. Aside from being barely visually different, it'll mean you can't compare spoke tension by pitch any more with that spoke.

fietsbob

Meaning no J bend at the head end ? (Not just a radially spoked conventional hub) .. that will be the difficult part to find
(try the high end seller's bike shops in Colorado?,
Length Measured?

an 0.1 mm difference in the center, between the butts, really wont matter. >true it to get the rim straight<..

(I have a (New XS) Schmidt-Brompton wheel with such a type of spokes & wheel hub design made to use that type
(except shorter of course)..






..

cpach

Straight pull/direct pull spokes are relatively common in the high end of the bike industry, to the chagrin of many mechanics. They are very easy to order from any major spoke manufacturer, though most shops won't bother trying to stock a run of different straight pull lengths/buttings. Most shops with a spoke cutting/threading machine will probably have some because they can cut them to length. This is not that weird.

mrblue

Why not? On a properly tuned guitar, in standard tuning, the low E has the same pitch as the high E string. The only difference is the octave and the string gauge. So theoretically a properly tensioned wheel with one slightly thicker (.1mm) spoke should still be able to be checked for uniform tension based on pitch. However, unlike a guitar, when tensioninng a wheel we are going for uniform tension. So the thicker spoke may simply sound a step or two lower, at the same tension as it's thinner neighbor. Would that be correct?

Bill Kapaun

Sure.
Can you show us the calculations to determine how much?

mrblue

No. I have no calculations. I was just thinking and wondering out loud.

cpach

E2 and E3 are different pitches; they are in standard music theory considered the same pitch class because of octave equivalency. A string (or spoke, in this case) will vibrate at a higher fundamental frequency at the same tension when it is narrower (assuming the same material). A difference of .1mm in a spoke is absolutely enough to make matching tension by matching pitch too inaccurate for the scrupulous wheel builder. For reference, I typically get spokes on the same side of a wheel to sound closer than a quarter tone--often within 15-30 cents. When I have to deal with this, I make sure to use a spoke tensiometer to even the tension of the different spoke, even when I use pitch almost exclusively to compare relative tension.