thinktubes 

I've been reading up on wheel truing and it seems many of the guideline suggest tightening to true the wheel. This is for an existing wheel not a new build.

Is there a case (outside of major surgery) where the spokes would be loosened instead of tightened?

mpetry912 

it's more complicated than that but if you tighten only you will end up with square wheels !

find a couple youtube videos on wheel truing and watch them.

it's hard to describe in a couple short sentences "how to true wheels" but - you are basically trying to make the wheel ROUND (radial) and STRAIGHT.(lateral)

to adjust the lateral truing - side to side wobble - you should loosen the spokes that go to the hub flange "towards" the deflection and loosen the ones on the opposite side. Work in groups of 4, tighten two and loosen two. For wheel "hop" then, yes, tighten two or four adjacent spokes. If it's a low spot, loosen two.

Go about 1/4 turn at a time, work in groups of four spokes and then go around the wheel and evaluate the overall tension and try to address any very loose or very tite spokes.

do you have a truing stand ?

Mark Petry
Bainbridge Island, WA USA

Phil_gretz

I would add that the resulting wheel should be both radially and laterally true, and have somewhat equal spoke tension all around. You can use a tension meter for absolute and relative tightness, but it's usually not necessary to obsess about this. "By ear" is generally accepted as close enough. Front spokes with the same tone when plucked. Rear non-drive side with the same tone, and then drive side with a higher tone due to higher tension. Of course, this assumes that you're beginning with a somewhat straight rim.

reconnaissance

My two cents: there are two reasons to true a wheel. 1) spokes have stretched over time, and need to be brought back in line. 2) sudden uneven stress on the wheel, like a crash, pothole, curb hit, etc. If the wheel itself is bent in this case, you will relax tension on some of the spokes so the wheel will go back to center and circle.

Mike

3alarmer 

.
...I find myself working on a lot of already built and used wheels that, for some reason, were built a little loose to start with. When you factor in that over the years, someone has done some truing who might not have been interested in balanced spoke tensions, I have now just taken up the routine of quickly checking around the wheel with a tensiometer before I start, to see where I'm at with this particular wheel. I know it sounds more laborious, but in most cases it saves time in the longer run. And while most of my efforts usually are directed at increasing tension on an under-tensioned wheel, I do find myself doing the final adjustments by both increasing tension a quarter turn, and decreasing it a quarter turn on the opposite side on the alternate spokes in an arc that needs to be pulled in one direction or the other to be in plane.

Bill Kapaun

I'm retired, so time isn't an issue and often hope I'd get the "opportunity" to "save" a wheel on a too miserable day to ride.
I take it a step further-
I have alligator clips in 4 colors.
After getting a "mental average" reading with the tension meter, I assign each color an appropriate value based on the expected deviation. Some colors +, other's - from the "expected norm".
This tends to show the forest AND trees together. If you have a "congregation" of 4 colors in a small area, that's a very good place to start.
It can also easily indicate- Save your time on a rim that's trashed.

Another trick I use is to set an adjustable wrench to the brake track width and run it around the rim. Sometimes curb damage becomes apparent or sometimes, just a cheap rim that varies 1/32" when new.

davidad

Spokes don't stretch past their yield point unless overloaded and about to break.

davidad

I adjust the lateral true on a built rear wheel using the NDS spokes only and either tighten or loosen as necessary. On fronts that I have built if there is a little lateral misalignment I tighten the necessary side.
On fronts with low tension I bring them up to tension and then finish the lateral true and stress relieve.

Wilfred Laurier

This is terrible advice. If you are sure this is what they are suggesting that I suggest you ignore any advice you get form those sources.

If just truing a slightly out-of true wheel (2 or 3mm or side-to-side runout), and you are otherwise confident that the wheel is properly built and has decent spoke tension all the way 'round, then you work your way around the wheel, tightening one spoke then loosening the next, so as to maintain the same overall tension in the wheel as you started with. The goal is high even tension in all spokes, but it might be difficult for a relative beginner to know what 'high' tension is. Others say you should get and learn to use a spoke tension gauge, and I don't disagree.

If the wheel has some loose spokes or has more severe side-to-side wobble, then you can work around the wheel and gradually bring loose spoke up to match the tension in the properly tensioned spokes, and, if necessary, loosen any that seem to be much higher tension than the others. If the rim is in known good condition (no dents or bends) then you can use the 'radial' trueness (up-and-down) to get spoke tensions balanced all the way around - where the rim is 'too high' you can tighten the group of spokes in that area to pull it closer to the rim, and where the rim is too low (the brake is coming closer to the tire), you loosen groups of spokes to allow the rim to go further from the hub.

NB- all truing should be done in small increments like ~half-turns of the spoke wrench, then move to the next spoke.

If the rim is dented or otherwise badly damaged and you need to get it as straight as possible to keep rolling until you can replace it, then you do whatever you have to do to get it straight - the spokes will likely be wildly different tensions around the spot where the rim is damaged. You cannot judge the quality of the truing job by the evenness of the spoke tension. Sometimes bending the rim back through brute force can get you in a better starting point for this type of operation, but you will never get it perfect and should still replace the wheel when possible.

thinktubes 

Thanks for the replies.

The wheel in question is a machine-built rear wheel that was probably under-tensioned. It stayed trued for about 200 miles and then developed a wobble.

I do have a truing strand and have built a couple of wheels, but nothing with a dish.

I have trued it once and released the stress, but a small blip had come back.

andrewclaus

I was taught when truing laterally, to loosen a spoke on the opposite side of the one you tightened, in order to maintain radial true.

And I haven't read every word, but I don't think anyone's mentioned wheel dish yet. I get some in the non-profit that have been poorly repaired. An example the other day was someone replacing the outside spokes on the drive side because the chain shifted into them, then tightened them too much. That wheel was 4 mm out of dish, and everything was as tight as it should be. I started by loosening one entire side a half turn and the result was nearly perfect--properly dished with moderate tension, and true.

WizardOfBoz

Yeah, I can think of a situation where you or someone else built a wheel and it ended up to be a bit out of true radially but with the spoke tension about right all around. To move the rim away from the center axis of the hub, you kinda hafta loosen some spokes. Loosen 2 or 4 spokes, or really, really tighten 32 or 34?

horatio 

Not meaning to hijack the thread, but what's the best way to correct for hop? I had to replace a spoke a few months ago, and ended up with the wheel WAY out of true. It's good now, save for the hop.

zacster

Hops are generally fixed by tightening. At the edge tighten in very small increments and more as you get to the center of the hop and then less as you move away again. Maybe do 5 spokes at a time. You want to maintain lateral true as you do it, but likely it isn't laterally true either.

AnkleWork

Yes always tighten only...until it tacos. Then loosen one-quarter turn.

reconnaissance

Correct. But they all stretch.

ThermionicScott 

If the rim itself is bent, just tweaking spokes until the wheel is true results in a wheel that may come out of true again soon. To fix the issue, you're either looking at cold-setting (bending) the rim, or replacing it.

ThermionicScott 

Spokes stretch elastically in normal use, but they should not stretch plastically. It's possible that if you think you're seeing the latter, it's really that the spokes have lost a bit of tension from settling into position, or the rim is yielding a bit at the spoke holes.

Wilfred Laurier

Except for at the elbows when the wheel is new. The elbows will usually plastically set in a position that allows the spoke to relax a bit. This is why machine built wheels loose tension and wind up with broken spokes after a few months of riding - the 'stress relief' that most builders do is actually to counteract the loosening caused by this, and my guess is that most machine built wheels skip this step.

ThermionicScott 

Right, that bit of plastic deformation should take place and be done before the user ever gets the wheel, I think.

Homebrew01

Sometimes. If a rim needs to move a bit to the right, and the spoke on the left is very tight, I might loosen the left spoke instead of tightening the right spoke.
Or I might loosen the left a bit, and tighten the right a bit....depends.

thinktubes 

Just got back in from the garage. Turns out one spoke was quite loose at the center of the blip.

did a combo of incremental tightening and loosing in the area. Did a few small tweeks to the radial true as well. Wheel is all good now.

thanks for all the replies - still learning here.

mpetry912 

you can approximate correct dish by "flipping" the wheel over in your truing stand, and work towards the center. It's not the fastest way but it will get you close to correct dish.

remember that each time flip the wheel over you wan to reduce the difference in dish by half.

If you can figure out which way the wheel needs to be "tightened" in order to achieve correct dish, that's a good way to arrive at correct tension once the wheel is approximately true.

Mark Petry
Bainbridge Island, WA USA