replace spoke - tension by sound?

Discuss light weight issues concerning road bikes & parts.
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ricorob
Posts: 50
Joined: Thu Feb 02, 2012 9:25 pm

by ricorob

I don't have a tension gauge, so I thought I'd tension the replacement spoke by plucking it like a guitar string. This should come close to evenly tensioned spokes during the truing process. Wheel is very round and true and all of the spokes sound about the same pitch. Anyone ever try this with long term success? Easton EC90 SL tubulars with sapim straight pull double butted spokes. Closest LBS that I trust is 180 miles round trip. :~(

eric
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by eric

It's the best way if you don't have a tensiometer. Of course the new spoke needs to be the same gauge.

by Weenie


mrfish
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Location: Near Horgen, Switzerland

by mrfish

There is no real need for a spoke tensiometer if you're just replacing broken single spokes in a well-built wheel. And if the rim is bent then you will feel the difference in tension when you use the spoke key.

The aim is to have a straight wheel, not one which plays a scale, so instead focus on tensioning the spoke to get the wheel straight. You just need to get enough tension in the new spoke to pull the wheel back straight. At this point the new spoke should make a 'ping' sound similar to the other spokes, i.e. it should have enough tension not to de-tension in use and come undone.

If you're just installing one new spoke in a well-built wheel, you should only need to touch that spoke to get very close to a perfectly true wheel if you're using modern stiff rims as the rim and spokes will not have undergone plastic deformation. A typical mistake is to change the tension in the next door spokes, which introduces hop. To avoid this I put a strip of tape on the new spoke.

If for example you run an shallow aluminium rim and lose 3 spokes in a crash, likely the rim will have permanently bent. By all means then try to straighten the wheel by replacing the spokes, but in all likelihood the spoke tension needed will be wildly different even on a front wheel (you will feel the tension difference from the spoke key). In cases like this it's best to replace the rim as the wheel is unlikely to be reliable.

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stella-azzurra
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by stella-azzurra

I was in the same camp I do not need a tension meter to build a wheel. Which is true.
But after getting a tension meter the wheel I build are way better now.
Doing it by feel is doable but you will not get the same results as you do with goods measurable numbers.

To replace one spoke and nothing else you can get away not using a meter if the wheel is built properly to begin with (as previously stated)

A tension meter is a tool to have if you are going to build some good, round, true, strong wheels.

It's a stella-azzurra recommendation. :thumbup:
I never took drugs to improve my performance at any time. I will be willing to stick my finger into a polygraph test if anyone with big media pull wants to take issue. If you buy a signed poster now it will not be tarnished later. --Graeme Obree

Snicks
Posts: 57
Joined: Sat Nov 12, 2011 8:33 am

by Snicks

+1^

If you're going to do it just once and unlikely to be ever/not very often in the future again, then it should be ok.
If you want to be able to build strong/reliable etc etc either get the LBS to do it, or get a tension meter :)

quattrings
Posts: 482
Joined: Sun Nov 14, 2010 10:25 pm

by quattrings

If the spoke broke at the elbow, you could just count the number of turns needed to unthread the nipple. This will give you an indication of how many turns the new spoke should need. Of course other spokes could easily have detensioned as a result of the broken spoke, so to get the wheel perfectly true again you have to check all other spokes as well.
Tensioning by sound is for the master wheelbuilders. Tensionmeters are a bit overrated in my opinion.

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WMW
in the industry
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by WMW

ricorob wrote:Anyone ever try this with long term success?(


If the wheel was straight before and the tension even, then tensioning that spoke until the wheel is true will work. No need to touch the other spokes unless it is necessary.

You need to thoroughly stress relieve that spoke, though.
formerly rruff...

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stella-azzurra
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Location: New York

by stella-azzurra

Yeah maybe the bicycle wheel master builder can also tension a harp

Image

:lol: :lol:

Who?! Who is the master builder?
Can a master builder play a tune with your built wheel?
What kind of tune would he play if he was a master builder?

:smartass:

If you are musically challenged like me get a tension meter.
I never took drugs to improve my performance at any time. I will be willing to stick my finger into a polygraph test if anyone with big media pull wants to take issue. If you buy a signed poster now it will not be tarnished later. --Graeme Obree

by Weenie


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