Re: [CR]tensionometers

From: "Mark Poore" <>
Subject: Re: [CR]tensionometers
Date: Sat, 20 Apr 2002 08:39:09 -0400

Just some of my thoughts on wheels and tensionometers after 30 years of building wheels and having learned from Boots Ward who built more wheels that anyone I can think of. Would you agree with that Larry B?

Having used most of the spoke prep stuff out on the market I have gone back to Linseed oil. It seems that it does a better job and lasts longer after many spoke adjustments. Not to mention it is about 1/100 the cost or less than store bought spoke dope.

I bought a Wheelsmith tensionometer several years ago for the shop and if my memory serves me correctly in the directions it says use the tensionometer as a guide and that different spoke gauges will have different tensions by that gauge for a built up wheel i.e. 14 gauges will have a different tension than 14/15/14 or 15 say for a properly built wheel because of the thickness of the spoke. As someone stated a round even hoop to start with would make a stronger wheel than one that isn’t round or even. On the rear wheel the drive side will carry more tension than that of the non-drive side because of the dish and the spokes are shorter. Most of this is covered in the book “The Bicycle Wheel”. The book even talks about plucking the spoke. Once I have gotten the spokes close to the tension I am looking for I check a couple of spokes with the tensionometer to see where I am at and the rest is done by plucking. I have found that a 1/8 – ¼ turn cannot be measured with the tensionometer, but the difference in tension can be heard by plucking.

Here at the Snowshoe Mountain Bike Center we are at ground zero of the unofficial product-testing center. In talking with Miles Rockwell at the NORBA Nationals here last year he said our course is the most technical of all the NCS DH courses and the other pros that I talked to agreed with that statement. I have spent entire holiday weekends doing nothing but rebuilding guest’s bent wheels. Although not road wheels or in particular classic road wheels the same principals hold true for a strong durable wheel. And a road wheel has a much easier life than that of a mountain bike wheel on the terrain here. Most of the failed wheels that we see are machine built wheels that are unevenly tensioned. One of the drawbacks of machine built wheels that I have seen is that the machine can build a straight and true wheel; it just can’t evenly tension that wheel. Outstanding shops will, at the time of build up of a bike, take the time and properly tension the spokes and put a drop or two of prep at the spoke where it enters the nipple so the new owner can leave the shop with strong wheels.

In closing when one considers the materials to build a wheel with one must think about the stress the wheel will be under once built. From the weight of the rider, the aggressiveness and the finesse of the rider, the roads or trails that the wheel will travel on have to be taken in to consideration. I am sure there are a few things I have overlooked here, but the sun is shinning and my mind is starting to drift off to thoughts of riding.

Don’t forget to oil your nipples before you twist them.

Mark, wheels don’t fail me now, Poore Snowshoe, WV

>From: Bicycle Classics inc <>
>Subject: Re: [CR]tensionometers
>Date: Fri, 19 Apr 2002 16:10:14 -0600
>The use of tensionometers is less important, I believe, on older wheels.
>On older wheels even if the wheel has kina uneven tension, the low tension
>spokes are still doing something - or maybe its because spoke tension in
>generall is more evenly distrubuted a good build is less important. Maybe.
>On modern high-dish wheels, though, if tension is uneven, some spokes may
>actually be completly untensioned. I think that on such wheels it is
>generally more difficult to "twang" a spoke on the non-drive side and
>identify what the tension is.
>More important than tensionometers, though, are 2 key ingredients to great
>wheelbuilds. The first is that spoke prep is super important - 5 or 6 speed
>wheels can be cheated on and oil will do the trick - but do that on a
>modern high dish wheel and everything will fall apart - literally.
>Secondly, the use of lighter guage spokes on non-drive rears really helps -
>and double butted on everything.
>Mike "now I just wheels for myself since liberation!" Kone in Boulder CO
>At 08:37 PM 4/19/02 GMT, wrote:
> >I have never used one personally and know people who swear by them. But
> >a lot of wheels in the 70's and 80's without one for myself and friends
> >to the best of my knowledge, never had a spoke break in any of them. In
> >I still commute on a set of clinchers I built in about 1973 and have
> >any problems.
> >
> >I have no doubt they are better at determining consistent tension than
> >method. But,I have always maintained that building strong straight wheels
> >as much art as science and some people were born with the aptitude for
> >Kind of like using a paint gun -- anyone can lay paint but only the
> >gifted can do it well.
> >
> >Kevin MacAfee
> >St. Paul, MN