# Radial truing



## redondoaveb (Jan 16, 2011)

I am trying my hand at wheel truing. I can easily true a wheel that is slightly out of lateral true. I decided to take an old 26", 36 spoke wheel and play with it. 

I loosened up all the spokes unevenly so the wheel was way out of true and decided to try truing it from there. Well, I got it laterally true but it is now out of round (not radially true). I know that I should tighten the spoke(s) at the high spot but if all the spokes are tensioned, what is the procedure for bringing it back to true? 

I now have a lot more respect for you guys that do this for a living (takes a lot of patience). :mad2:


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## Zen Cyclery (Mar 10, 2009)

Vertical hops can be much more difficult to eliminate than lateral play. The best thing that seems to work for me is to listen to the tone of the spokes. 

First off, find your low spot. Then take your spoke wrench and tap the drive side spokes near this low spot. You will hear differences in tones. The lowest tone is the spoke that has the lowest (relative) tension. Once you have found the lowest one, test the adjacent 2 spokes on the non drive side. You should hear a tone variation with these as well. Pick the lowest one on the non drive side too (keep in mind they should be adjacent to each other). 
Depending on how bad your hop is, you will want to tighten both of those spokes, an equal amount. Maybe start with a quarter turn. Then go from there. 
This same method applies to high spots too, but in that case your looking for the highest tone spokes and then loosening them. 

IMPORTANT!! Spoke tone is only effective for measuring relative tension, not absolute!!


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## rruff (Feb 28, 2006)

Since you already made the tension uneven, your first step is to make it even again. 

Start with *very low and even tension*... before you worry about truing. Then bring the tension up gradually, checking the true and evenness of tension at each stage. When you get the tension up to the desired level, stress relieve and repeat... several times... for a new wheel. An existing wheel is hopefully already stress-relieved. 

Note that if a wheel has been properly built it should not need truing unless there has been a shock severe enough to make one of the components yield... or possibly a spoke went slack and a nipple unscrewed. This should be a very rare event. 

It could also signal that a spoke is about to break or the rim is cracked, so check those parts. 

If a wheel is out of true because the rim has been bent, there is no way to adequately fix that... you need a new rim. 

In every case, spokes will only get loose in use not tighter... so look for the minimum number of spokes (usually one) that will make the wheel true if it is tightened.


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## Mike T. (Feb 3, 2004)

In addition to what these fine fellows said, I find it much easier not to get rim hops in the first place. If you read my site you will find tips for this.

I think most people get hops because they lose their place during tensioning and some spokes get more or less turns than others - assuming a rim is reasonably round to begin with. I have some tips on my site for not losing your place. I don't remember the last hop I had to remove from a rim. I know I've ignored some very minor ones.


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## redondoaveb (Jan 16, 2011)

Zen: When you find your high spot, I thought you were suppose to tighten that spoke in order to pull the rim in towards the hub. Is that not correct?

rruf: Well, at least I did part of it correct (I think). I did bring the spokes up to partial tension by tightening all spokes a half turn at a time and then when they all were partially tensioned I started the straightening process.

Thanks for all the input as I need all I can get.


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## SauronHimself (Nov 21, 2012)

Learning to true your own wheels begins as a painstakingly slow process, and for someone like me who doesn't have much patience it doesn't bode well. One thing that can give you a good start toward a rounder wheel is a tension meter. I use the one by Park Tools.


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## redondoaveb (Jan 16, 2011)

Sauron: I agree with you on the patience part of truing. When I get frustrated I just back off and come back to it later. Also, I've thought about the tension gauge, maybe I need to break down and get one.

Mike T: I have briefly looked at your site in the past, I think I need to revisit it and read a little more (ok, a lot more) in depth. Don't be surprised if hit you up for some more info (that goes for all the wheel builders). :thumbsup:

Thank you guys for all your help.


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## Kerry Irons (Feb 25, 2002)

rruff said:


> Since you already made the tension uneven, your first step is to make it even again.


The key point. Starting with a wheel that has widely varying tension is often the path to a very bad situation. You can get a wheel true with uneven tension but it will likely not stay true and will probably eat spokes.

As a matter of terminology I think some people are using "high spot" and "low spot" in different ways. For me, a high spot is where the rim is farther from the hub and a low spot is where the rim is closer to the hub. Zen appears to be using the opposite convention or he mis-spoke (pun intended).


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## redondoaveb (Jan 16, 2011)

Kerry Irons said:


> The key point. Starting with a wheel that has widely varying tension is often the path to a very bad situation. You can get a wheel true with uneven tension but it will likely not stay true and will probably eat spokes.
> 
> As a matter of terminology I think some people are using "high spot" and "low spot" in different ways. For me, a high spot is where the rim is farther from the hub and a low spot is where the rim is closer to the hub. Zen appears to be using the opposite convention or he mis-spoke (pun intended).


After basically starting from scratch with the current wheel I've been playing with, I now understand the need for all spokes to be tensioned properly (learn from your mistakes). 

My interpretation of "high spot" is the same as yours. I had a feeling Zen meant the same thing, we just weren't on the same page.


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## jnbrown (Dec 9, 2009)

i follow the Zen convention,
high spot is above the guide on the truing stand, low spot is below it.
Many times a rim is not perfectly round or laterally straight and you have make a trade off between even tension or a perfectly true wheel. There can also be a hop at the joint and you pretty much have to live with it.


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## redondoaveb (Jan 16, 2011)

jnbrown said:


> i follow the Zen convention,
> high spot is above the guide on the truing stand, low spot is below it.
> Many times a rim is not perfectly round or laterally straight and you have make a trade off between even tension or a perfectly true wheel. There can also be a hop at the joint and you pretty much have to live with it.


If you wanted the perfectly true wheel, would you be better off with some spokes under tensioned instead of being over tensioned?


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## mikerp (Jul 24, 2011)

redondoaveb said:


> If you wanted the perfectly true wheel, would you be better off with some spokes under tensioned instead of being over tensioned?


Under tensioned (or better stated tension less than your target margin but still having some tension vs no tension at all) will not cause a failure.
Over tensioned puts you in the position of breaking things (rim, spoke, nipple), once something breaks your wheel will be out of true.
Thus, avoid over tension.


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## rruff (Feb 28, 2006)

redondoaveb said:


> If you wanted the perfectly true wheel, would you be better off with some spokes under tensioned instead of being over tensioned?


You are better off with tension as even as possible... true is less important.


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## Kerry Irons (Feb 25, 2002)

*Conventions*



jnbrown said:


> i follow the Zen convention,
> high spot is above the guide on the truing stand, low spot is below it.


I'm still confused by this convention. In the truing stands I have used, when the rim is farther from the hub (what I call a high spot) then the rim is above the guide on the truing stand. Zen said the opposite. In a "perfect" wheel (all components uniform) then almost by definition a high spot would mean less than average spoke tension and a low spot would mean greater than average spoke tension. You would "pull in" the high spot by increasing tension on the spokes "under" that section of the wheel and "let out" the low spot by decreasing tension under that section of the wheel.


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## Zen Cyclery (Mar 10, 2009)

Sorry about the confusion here guys. Usually, I refer to a low spot due to it relative position to the truing arm. And relative to the hub, this would be the highspot.


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## redondoaveb (Jan 16, 2011)

Thanks for the clarification guys. I looked at a wheel today that had a low spot (1/4") (relative to the hub) and tried to true it. I loosened spokes, tightened spokes, cussed at the spokes, talked dirty to the spokes, pleaded with the spokes and still couldn't get rid of the low spot. Does there come a time when the wheel is too out of round that spoke tensioning won't work? If so, what is the next step, loosening all the spokes and physically tweaking the wheel by hand?

Damn, this can be frustrating.


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## redondoaveb (Jan 16, 2011)

Okay, I got rid of the low (flat) spot on the wheel I was working on. I removed the DS and NDS spokes in the area of the flat spot, put a rag over the nipple side of the wheel and beat it with a hammer. Re-installed the spokes and trued the wheel. 

There is still a little bit of a flat spot but it actually came out pretty good. I figured if it didn't work it was just a spare wheel off a rental bike, I would have thrown it away if I couldn't get it repaired. 

Precision work is my speciality.


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## Kerry Irons (Feb 25, 2002)

redondoaveb said:


> Okay, I got rid of the low (flat) spot on the wheel I was working on. I removed the DS and NDS spokes in the area of the flat spot, put a rag over the nipple side of the wheel and beat it with a hammer. Re-installed the spokes and trued the wheel.
> 
> There is still a little bit of a flat spot but it actually came out pretty good. I figured if it didn't work it was just a spare wheel off a rental bike, I would have thrown it away if I couldn't get it repaired.
> 
> Precision work is my speciality.


Congratulations! You now qualify as a shade tree mechanic. Our motto is "If it doesn't fit, get a bigger hammer."

An alternate technique would be to loosen/remove the spokes as you did, loop a wide strap/belt/rope through the opening, tie the strap around a post/tree and yank on the wheel. This is less likely to ding the rim compared to hitting with a hammer. If a low spot will not come out of a wheel when you completely loosen the spokes at the low spot and tighten everything else then you have a bent rim. It will never be great but this technique will result in a rideable wheel.


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## redondoaveb (Jan 16, 2011)

Kerry Irons said:


> Congratulations! You now qualify as a shade tree mechanic. Our motto is "If it doesn't fit, get a bigger hammer."
> 
> An alternate technique would be to loosen/remove the spokes as you did, loop a wide strap/belt/rope through the opening, tie the strap around a post/tree and yank on the wheel. This is less likely to ding the rim compared to hitting with a hammer. If a low spot will not come out of a wheel when you completely loosen the spokes at the low spot and tighten everything else then you have a bent rim. It will never be great but this technique will result in a rideable wheel.


The hammer routine was the last resort on a wheel that I didn't care if I screwed up. I just didn't want it to get the best of me. :mad2: I actually did remove the spokes in the flat area and hung it over a horizontal pipe and hung on it like a wild ape. That sucker wouldn't budge. That's when the shade tree mechanic in me came out. Rim still looks good and is still functional. I won this round.


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## TomH (Oct 6, 2008)

Starting from scratch, tension up the wheel to almost slack. Just enough tension so nothing is technically loose. Now do all your radial and lateral truing! With such low tension is very easy. 

Once its nearly perfect, start adding tension. Get it to about 1/4 max tension and again true the whole thing. It shouldnt need much. Recheck at 1/2 your tension goal, then tension the whole thing up. You should have a hop-less wheel now! You should also have pretty even tension. The big key is to not turn the nipples more than half a turn. Some guys even do 1/4s. The less the better, just takes longer.


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## redondoaveb (Jan 16, 2011)

TomH said:


> Starting from scratch, tension up the wheel to almost slack. Just enough tension so nothing is technically loose. Now do all your radial and lateral truing! With such low tension is very easy.
> 
> Once its nearly perfect, start adding tension. Get it to about 1/4 max tension and again true the whole thing. It shouldnt need much. Recheck at 1/2 your tension goal, then tension the whole thing up. You should have a hop-less wheel now! You should also have pretty even tension. The big key is to not turn the nipples more than half a turn. Some guys even do 1/4s. The less the better, just takes longer.


Tom, thanks for your input. I'm finding out that everything needs to be done in baby steps (and a lot of patience).


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