My Ksyrium Elite looses it's true quite often
 

Hi,

I have problem on my Ksyrium Elite wheel.
It had become out of true three times in 3 months or 1700 miles of my commute and joy ride.

Every time one of the spokes lost tension suddenly. It was so out of true that the wheel rubbed brake pad.
Last two happened after hill climb (like 15% grade in one section).

I used Park tool spoke tension meter to make sure tension variation was within 10% range when I trued the wheel.
It only happened on rear wheel. Front has been always perfectly true.

Does anybody encounter similar problem ? I am trying to figure out what could be the cause and how I can prevent this. I would appreciate any input.

Thank you
Koshi

Been there, done that. More so when I was a bit heavier at 190lbs.

in spite of what others might say, that is not a clydsdale wheel. i rode them for about a year and spent more on truing than on the wheels in the first place. i even went so far as buying a second rear wheel as a backup.

after spokes started braking, mavic replaced the original rear wheel and i sold them at a swap meet.

good luck

I'm 205lb and had the same problem with my rear Mavic Open Pro 32 spoke wheel, one that should be fine for my weight. The problem is that the heavier you are the higher the spoke tension has to be for the wheel to remain stable. From the builder the drive side spokes were set at about 100kgf. To stabilize it, I ended up having to raise the tension to around 125-130kgf. At any tension much lower, the non-drive side spokes wouldn't be tensioned enough and at least one would work itself loose in short order throwing the wheel out of true.

Gerd Schraner, author of the Art of Wheelbuilding, suggests that when setting the drive side tension, tighten the spokes so that the rim is pulled all the way over to the drive side, adjusting the non-drive side only as much as is necessary to true the wheel. Only then do you adjust the non-drive side to properly dish the wheel. Doing that ensures the non-drive side spokes are at their highest possible tension.

Interesting approach. I don't have Schraner's book so I'm not quite sure what the technique is. Do you initially adust the drive-side spokes so they are "vertical", i.e. in the same plane as the drive side hub flange?

Pretty much. His actual truing procedure is 19 steps (pg 86) with the 2nd step aligning the rim as far to the right (viewed from the rear) as possible.

On page 83 he makes this comment:

"During the truing stage of the rear wheel, one should try to position the rim as far to the right and as far beyond its actual central position as possible. Finish truing the wheel, install the right hand side spokes with their optimum tension and never mind about tensioning the left-hand for the time being. The wheel is dished towards the left definitive at the end of the truing stage.

This is practically the only way to achieve the highest possible spoke tension on the left-hand side. If this is not done, then it will be very difficult to get enough tension into the left-hand spokes."

His definition of "optimum tension" for the drive side spokes is as high as the rim will allow and still react properly to tension tweaks.

A thorough reading of Schraner's very fine book will reveal that he is a firm believer in the use of tensiometers. He goes so far as to admit that, after starting to use this tool, his own "sense" of tension was not very accurate and would vary from day to day. I have talked to Gerd and he says to use a tensiometer and consult the rim manufacturer to get the maximum allowable tension for drive side spokes.

Rears should be built up to the point where the drive side tension is at, or near, the rim manufacturer's max spec. Rounding, lateral truing, and dishing, should be going on, incrementally, throughout the process. If you do it right, the last tweak you should be making is the final dishing. Smart wheelbuilders try to get the rounding out of the way early in the build. Rounding often takes big adjustments. Once it's good, the lateral truing and tensioning don't often change the rounding by a lot. Then you incrementally increase the tension in several steps to get to the maximum. Again, a smart wheelbuilder will do lateral truing AND dishing in the same step. It's a little bit of a chess game. You need to look ahead to see where you want to get to and, by doing so, can kill the truing and dishing at the same time. That's a bit advanced for a lot of people, so the simple method is to do rounding (radial truing), lateral truing, dishing, increase tension, and stress relieve. Rinse and repeat, rinse and repeat, ...

It should take three to four iterations of those five steps to finish the wheel. A well built rear wheel will have all the drive side spokes within 5-10% of each other. You are going to get the biggest variations on either side of the seam, so don't stress out about that. Most wheels are going to have one high tension and one low tension spoke. Rims are not perfect.

If you want to build consistantly good wheels get a tensiometer and dishing gauge. That business about flipping the wheel over in the truing stand is pretty "iffy" in my opinion. I use a Park TS2 all the time and the wheels move in the stand almost every time you turn a spoke. Trying to use the stand to determine the dish just slows you way down. You can get a decent tensiometer and dishing gauge for well below $100. Once you use a dishing gauge the first time you will become a believer. Well worth it if you're going to be doing this in any volume.

Sorry, I got off topic on my last reply ...

Koshi, it would help to know if, during any truing of your wheel, any lubrication was ever applied to your nipples???

quoting what you said "a well built rear wheel will have all the drive side spokes within 5-10% of each other" can you please explain further and what is stress relieving?

Stress relieving is a process that insures the spokes are not "wound up". This is not an easy thing to describe. It's covered, in depth, by both Schraner and Brandt. I'd suggest you read up (from those guys) on this process. Sorry for bailing out on this one, but it IS a very necessary step and I could show you in seconds. But, to describe what's going on is kind of difficult.

Relative tension is a bit easier. For example, if the maximum tension on your rim (as specified by the rim manufacturer) is 110 kgF, then you take 10% of that and subtract it. So, the high end of your range would be 110 and the low end would be 99 kgF (= 110 - 11). If you want closer relative tension you would use a 5% range. So, that range would be from 110 to 104.5. The closer, the better. The narrowness of the range is going to be determined, somewhat, by the quality of the rim. Higher quality rims tend to be easier to get into narrow range.

now this is weird. i go 215lbs. and got elites on my c'dale six13 team. i could not be more happy with them. i have over 5000 miles on them and they are still perfectly true! and i am very fussy about that! the only problem i had with them was that they take about 1000 miles to wear n the dust seals. a lot of drag up to that point but now they spin forever perfectly true.

Not necessarily weird. Alot of the states that wheels get into has to do with individual riding styles and just how hard the rider is on wheels. When you ride with other people watch how people ride and how they take bumps. There are a LOT of people who hardly ever get out of the saddle to reduce the impact of a bump on their bike. This accounts for a lot of wheel problems - even with lightweight riders. And, on the other hand, there are plenty of big riders that use their arms and legs as shock absorbers and "unload" their weight on the bike in prelude to taking a bump. There is no doubt that there is real cause and effect going on here.

Now, I grant you, that explanation is not all of it. But, it's a pretty important piece of the puzzle.

There are some things we'd rather not know about koshi's nipples