Whiteboog

Evening all,

I am in the process of giving my bike a good going over ready for the best of the summer, and part of that involves sorting out the state of my rear wheel.

Over the past year or so, I have made 'on the fly' adjustments in order to true the wheel each time it goes out of line, with very little method to my approach, save to tighten or loosen as suits.

As a result of this the wheels is consistently out of true, and spoke breakage is becoming very common. I suspect this is less an underlying issue with the wheel however, and more a result of my dodgy truing.

Rather than trying trying to fix the issue by painstakingly going from one side to the other and adjusting spoke pairs, I wondered if it would be acceptable to simply loosen all of the spokes to a set point (i.e. where the thread is just visible) then tighten them all up equally. Then go through the usual truing process.

I can think of no reason logically why this should not be viable, but I am a little concerned as I have not seen it recommended at all through my google research, save in some wheel building literature, which of course assumes a start from scratch.

I would be grateful of any advice.

James

berner

I would expect the procedure you outlined would almost work. For the last bit of truing I flip the bike upside down and spin one of the wheels then touch a felt tip pen to the rim with my hand resting on the frame. This leaves a black streak on the rim where ever it is high. Adjust thusly and wipe the rim clean until the felt pen leaves a continuous streak, taking care that the wheel remains exactly centered in the frame. The rim can be trued to within 1/2 mm or better with a bit of patience. When frustrated, a cup of tea helps.

Bill Kapaun

IF spoke breakage is becoming common, replace them!
They have reached their fatigue life.

Keep in mind, that a wheel with dish (rear or disc brake) will have different tension from one side to the other.

Retro Grouch 

There's "out-of-true rim" and there's "bent rim". They're not the same thing.

I's loosen all of the spokes until exactly 1 spoke thread shows, then I'd evaluate the rim. If the rim is basically straight, that's just out-of-true. Gradually retensioning and truing the wheel will pro0bably work.

If the rim looks all wonky with maybe some of the spokes still a little tight, that's a bent rim - a much bigger deal. You can try to bend it back before fiddling with the spokes but I've gotten to the point that I just start over with a straight rim.

prathmann

Agreed. Once you have more than a couple spokes fail (and it's not from an obvious cause like a stick in the wheel) then there are probably several others that will fail soon. I wouldn't go through the amount of effort envisioned in the OP with a set of spokes that are likely to be untrustworthy. Start over with a new set of spokes.

RubeRad

If you're breaking spokes, it's likely you're riding a too-low-spoke-count wheel for your weight.

Whiteboog

Thank you everyone for all the advice. Most helpful.

Bill regarding your point:

I have read that this is the case, and it certainly makes sense. Am I correct in that the drive side has double the tension to the non-drive side? If so does that mean that after I have loosened all my spokes equally, I ought to tighten those on the drive side twice as much as those on the non-drive side before I start to tackle the job of removing any wobbles.

I do of course note the reply from the gentleman regarding the fact the rim may itself be bent, and I will check for this. I am a tad heavy, and I rode for sometime to work and back with a panier too, so no doubt this will have taken a toll.


Thank you for the help.

Bill Kapaun

For "typical" rear wheels with cassettes/freewheels, your NDS tension will range from about 55-70% of DS tension.
The wider (more speeds) the cassette exacerbates this problem. Some hubs have better flange offsets in regard to center of the wheel than others.

Don't assume turning the nipples on one side twice as much results in exactly twice the tension. Since the spokes run at different angles to the hub, they interact to a slight degree.
Typically, when tensioning a wheel, we'll have the "slop" out of the NDS spokes + a LITTLE bit.
Then we concentrate on the DS spokes, getting them to about 90% of final tension, (about 110kgf or so) working in multiple steps, keeping the rim concentric to the hub.
Then we tighten the NDS (in steps) to get the proper dish.
That will get you very close.

CliffordK

Are you truing the wheel on a stand, or on the bike?

One of the most annoying things to deal with is a bad hop.

Unless you have at least moderate 3-Dimension truing capabilities, your method of loosening then re-tensioning the spokes will inevitably give you a hop.

Breaking spokes is a problem. And it is not only weight&number of spokes. As others have mentioned, fatigue life, and perhaps the brand of spokes. I've been having some issues with an older 36h front wheel of unknown age, with unbranded spokes (3 broken spokes so far). Now I think that mixing DT and unbranded spokes may be a problem as they may have different stretch qualities.

Anyway, as was mentioned, if you're doing 50% of the work to detension and retension 100% of the spokes, I'd encourage you to just buy all new spokes, and evaluate the rim at that time too.

How are you estimating spoke tension? The last time I tried to true by tension, my wheel was all over the place I wouldn't worry about the exact DS/NDS tension. 2:1 may be close, but there are a number of other factors including exact wheel design, so you need to tension until you get the rim centred on the lock nuts. Just simply replacing the axle on my nephew's bike, and I threw off the dishing.

There are a few sub-$100 truing stands available. My father built my stand years ago (hopefully to be upgraded this summer). A pen is used to gauge wobble & hop (wobble is easiest to fix).


(teaching the next generation)

79pmooney

And to add to the tightness drive-side to non-drive-side and turns required for each - the drive and non-drive side spokes may well be different lengths. Building with shorter drive side spokes is common. They may also be different thicknesses, the drive side being thicker. So follow Bill's sequence and don't bother comparing turns of one side to the other.

Ben

Whiteboog

Thank you for the responses.

Bill your method sounds very sensible, and I will give it a go.

79pmooney I realise that trying to true by tension alone is not viable, rather I hope to try and reset some of the ridiculous and difficult to identify tension imbalance I have created by truing on the fly. By getting a moderately even tension to start with, I should be able to go forward from there - as one would if they hadn't previously bastardized their wheel.

I am just truing on the bike for the moment, as funds aren't great and I lack even the room to put together and store a half decent custom truing stand, let alone having the materials on hand with which to do so - though I am very impressed by your own. I really need new wheels in truth, but I just need to keep the ones I have going until I have the spare cash to get a new set.

As for hop, I will simply rig something to the frame which will allow me to identify vertical imbalance and adjust accordingly.

I believe I have plenty to be going on with, and thank you all again for your help.

James

davidad

You left out a lot of info that would help us help you. If you are heavy and on a low spoke count wheel the cure is a new wheel with more spokes.

Starting with no tension and retruing the wheel is a good idea. You do it in stages starting with trying to get the wheel radially true with a little attention to the lateral trueness. As the tension increases you can pay more attention to the lateral and adding tension. Browse through this until you find what you need. This is the wheel builders' bible. https://poehali.net/attach/Bicycle_Wh...bst_Brandt.pdf

SBinNYC

Loosening all the spokes to the same point will work, if all the spokes are identical (on each side for dished wheels) - they have the same length and the same amount of thread on the spoke, same length nipples, etc. You stated that some broken spokes have already been replaced. The method of using visible threads to determine that all spokes start at the same point will fail unless you are certain that the replacement spokes and nipples exactly duplicated the original ones. This is another reason for starting with all new spokes and nipples besides the inference that many of the remaining spokes already weakened.