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Discussion Starter · #1 ·
So I built a rear wheel for my 24" DJ and it's been awesome. I was running a 2.5" rear tire, so any sensitive deviation in the lateral/vertical truing was kind of washed away with all that rubber on there. Plus, this bike saw a huge amount of rear-wheel landings and general abuse, so I was fine ballparking the truing.

However, I just finished building up my SS 29er wheels, and I want to get more involved with getting the job done right. I'm using Sun Rhyno lite 36h hoops, surly bolt on disc hubs, and DT comp spokes/nips. The wheels are wrapped in 2.3 Schwalbe Big Apples.

After getting the wheels built and trued to the most of my experience, I have a few problems. First off, both wheels have about a 1.5mm vertical hop I simply cannot get rid of. I spent literally two hours on each wheel trying to fine tune it, but I could never get the vertical hop to go away completely. Lateral truing was much easier to get within a 1mm margin. I guess I'm wondering what constitutes a 100% "true" wheel, and if there are any techniques to help pull out the hop.

My second problem is dishing. My front wheel sits about 5mm to the right side, and is clearly not centered in the fork. Does this require the gradual loosening of spokes on the right flange, and tightening of the left to pull the wheel over, even though it needs to move a significant amount to the left? Or is it ok/normal to have a little bit of offset on a front wheel?

Thank you for any response!
 

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When it comes to "hop" you have to be aware whether the hop is at the rim weld or not. If it is at the weld then some hop will probably always be there. If it's not at the weld then it was induced by the spokes not being tensioned equally. I talk about this in my sig info.

1mm trueness is a lot of wobble. If you've been playing around for a couple of hours then you probably have the tensions all out of whack and that isn't good. Tensions should be very close to equal.

Of course a "100% true wheel" is a dream and really not necessary anyway. Lots of us can get them easily within 0.003" - 0.010" (three to ten thou, where 3 thou is about the thickness of a piece of paper). But that level of trueness isn't beneficial. Equality of tension and acceptable overall tension is much more important. That plus stress and windup relief.

Yes the front rim needs moving over. If you have to ask that question then it concerns me as to what else you're not sure about. I'd strongly suggest you read my sig info and get Roger Musson's wheelbuilding e-book.
 

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Discussion Starter · #3 ·
I'm not scared to work on building wheels or getting it right the first time; I understand that there's going to be a lot of trial and error. I mean, I tore down the back wheel after an hour or two of truing because I wasn't happy with where it was going. I've got patience, but definitely need assistance.

I used Sheldon Brown's guide as well as some you tube videos on how to true.

The hop on the wheels is indeed at the weld. I'm familiar with windup relief and spoke tension, but in the end I just felt like I couldn't make the set any better.
 

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Yo! said:
The hop on the wheels is indeed at the weld. I'm familiar with windup relief and spoke tension, but in the end I just felt like I couldn't make the set any better.
Then the hop might not be curable. I would be concerned as you won't feel it while riding. In the end we all get to the stage of not being able to make the wheels any better. Then we all do the same - quit & go ride.
 

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Discussion Starter · #5 ·
Hahha that's pretty much where I got to and said eff it, and threw the tires on. But when I wake up the next day I still think I can make them better...

I'm reading your write-up; it's awesome. I'll give it another go tonight when I get home and see if I can't make them better. Right now I guess my most pressing issue is to get the front wheel centered up in the fork.
 

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Yo! said:
My second problem is dishing. My front wheel sits about 5mm to the right side, and is clearly not centered in the fork. Does this require the gradual loosening of spokes on the right flange, and tightening of the left to pull the wheel over, even though it needs to move a significant amount to the left? Or is it ok/normal to have a little bit of offset on a front wheel?

Thank you for any response!
I would start be loosening the right side by 1/2 turn, then tighten the left by 1/2 turn. Continue until it is centered. You can also do the tighten/loosen at the same time but it can be less confusing to do one at a time.

Generally, I like to get the wheel true/round/dished at each stage of the tensioning. If there are big differences it is much easier to correct at low tension than high. And keep the tension even/balanced throughout. You will have a much better wheel in the end.
 

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Yo! said:
Hahha that's pretty much where I got to and said eff it, and threw the tires on. But when I wake up the next day I still think I can make them better...
We've all been at those two places too. It's always a conundrum - are they good enough or should I try harder? Both usually prevail and in different orders.
 

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Yo! said:
My second problem is dishing. My front wheel sits about 5mm to the right side, and is clearly not centered in the fork. Does this require the gradual loosening of spokes on the right flange, and tightening of the left to pull the wheel over, even though it needs to move a significant amount to the left? Or is it ok/normal to have a little bit of offset on a front wheel?

Thank you for any response!
I have the same problem, except it's off slightly to the left. I got it this way from the bs. Is spoke adjustment the only fix for this? Excuse the newbie idea, but would adjusting the alignment of the hub i.e shifting the axle in the hub over to the left (excuse the lack of proper terminology) make any difference? I can see how it might not, but could it be possible?
 

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2_WD said:
I have the same problem, except it's off slightly to the left. I got it this way from the bs. Is spoke adjustment the only fix for this? Excuse the newbie idea, but would adjusting the alignment of the hub i.e shifting the axle in the hub over to the left (excuse the lack of proper terminology) make any difference? I can see how it might not, but could it be possible?
Doing it your way (which is absolutely not the way to fix a dishing problem) just throws the rotor alignment off (assuming disc brakes). Fix the real issue. And of course with some hubs, your way just isn't possible at all.
 

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Discussion Starter · #10 ·
I got home and worked on the dish and got my wheels completely straightened out!

It was very easy. Thanks for all of the good input. I'm finally satisfied with the finished set of wheels.

FYI, dress shirt collar stays work really well as indexing markers when truing in the fork.
 

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Mike T. said:
Doing it your way (which is absolutely not the way to fix a dishing problem) just throws the rotor alignment off (assuming disc brakes). Fix the real issue. And of course with some hubs, your way just isn't possible at all.
Thanks, i appreciate the guidance. :thumbsup: Didn't think about the effect it will have on the rotor...haaaaack, sometimes perfectionism drives ya crazy!
 

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Yo! said:
FYI, dress shirt collar stays work really well as indexing markers when truing in the fork.
:rolleyes: :eekster: Riiiigggghhhhtttt!! Now I've heard it all! For years I used thumb, brake pads or screwdriver. I gotta say I never tried your method though :eek:
 

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Discussion Starter · #13 ·
Mike T. said:
:rolleyes: :eekster: Riiiigggghhhhtttt!! Now I've heard it all! For years I used thumb, brake pads or screwdriver. I gotta say I never tried your method though :eek:
Well I tried using a cigarette butt, a used toothpick, then a coat hanger, but the collar stays seemed to get the job done just right!
 

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Yo! said:
Well I tried using a cigarette butt, a used toothpick, then a coat hanger, but the collar stays seemed to get the job done just right!
Ciggie butt? I hear the filter end does a much better job. Plus the rim doesn't get nicotine stains :D
 
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