Bicycle Mechanics - What did I do wrong rebuilding this wheel?

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MrCjolsen
01-07-08, 01:06 PM
36 spoke Alex DA22 rear. Bought very cheap on eBay (new, $100 for the set with tires and tubes). After about 1500 miles, it wouldn't stay true, started breaking spokes, and developed a bit of a hop, so I retired the wheel and got a new rear wheel (Mavic T520, hand built at the LBS).

That was a year ago.

I got wheel building tools for Christmas (truing stand, tensionmeter, Jobst Brandt's The Bicycle Wheel).

So I decide to try rebuilding this wheel as my second project (first was a replacing the hub on my fixed gear). I figured I'd use it as a backup that I could have different tires on.

I loosened every spoke until threads were visible.
Put a dab of Prolink in every nipple.

Got the wheel centered and round by turning a few spokes with my fingers.
Turned every other spoke with my fingers until it started to seat in the rim. Before doing this, you could shake the wheel longitudinally and laterally.

Then I started bringing up tension while keeping centered and round.

At one point I needed to re-dish the wheel by almost a centimeter.

Finally, I had 110-140 tension on every drive side spoke (per Alexrims website) The wheel was true, and the hop was less than 1mm by about a half. Spoke tension on the left side was fairly even. Moreover, getting to this point was not difficult, indicating that the rim itself is fairly sound.

Stress relieved the wheel and it remained true.

Rode the wheel. No pinging sound whatsoever upon first loading (I took great care to avoid spoke twist). After a short ride, it remained true. So I thought every thing was fine.

I get to work. I have a 14 mile commute. I weight 205 and was carrying about 15lbs in panniers. So there was about 150 pounds on the back wheel. I was using 32mm tires.

I check the wheel at work, and it's seriously out of true - about 2mm.

So then ....

1. Am I trying to polish a turd. Is it possible that a cheap rim and cheap spokes will never perform to my expectations. Mind you, this wheel popped a spoke a very short while after I had it professionally trued.

2. Was the Prolink a bad idea? Jobst Brandt says to lubricate spokes. I chose the Prolink because of it's penetrating properties.

3. I needed to re-dish this wheel quite a bit. I notice that there's considerable clearance between the first cog and the frame when the wheel is installed. That means that it could be dished considerably more than it needs to be. I could re-space the hub, moving it about 5mm to the left and take some of the dish out of the wheel. Could that be the root of the problem?

4. My initial method of getting the wheel round and true was to tighten 16 key spokes with my fingers (the two on either side of the valve hole, the four directly opposite those, and the eight spokes that were perpendicular to those (forming a cross, more or less). Then I twirled the remaining spokes with my fingers until the nipples contacted the rim. Only then did I start brining up tension. Anything wrong with doing it this way?


trigger50
01-07-08, 03:06 PM
Have you a dishing tool. The wheel should work for you, might need some more adjustment. You seem to have a problem with the dishing.
Brian

Al1943
01-07-08, 03:27 PM
3. I needed to re-dish this wheel quite a bit. I notice that there's considerable clearance between the first cog and the frame when the wheel is installed. That means that it could be dished considerably more than it needs to be. I could re-space the hub, moving it about 5mm to the left and take some of the dish out of the wheel. Could that be the root of the problem?


Reducing the dish offset could help considerably. It's the low tension spokes that most often break.
Typically on multispeed bikes the non-driveside spokes have the lowest tension due to the hub offset. If you could move the hub so that the smallest cog is closer to the frame (that would be a move to the right when viewed from behind) then re-dishing would mean an tension increase in the non-driveside spokes decrease in the driveside spokes.

Al


well biked
01-07-08, 03:31 PM
Finally, I had 110-140 tension on every drive side spoke (per Alexrims website)

It sounds like the problem with the wheel coming out of true is that your driveside spoke tension is not even enough. Maybe the rim is screwed up to the point that it's not possible to get the spokes evenly tensioned and have the rim round and true.

The 110-140 kgf figure is what's acceptable for the driveside spokes on that rim, but it doesn't mean you should have the driveside spokes varying that much. If you decide to go with 120 kgf on the driveside, for example, you should try and tension all the driveside spokes to as close to 120 kgf as you can. You should be able to get within 10% (or less) of that figure, with the wheel true, round, and dished correctly. Even spoke tension is very important, or a wheel will tend to go out of true often-

MrCjolsen
01-07-08, 03:32 PM
The wheel is dished insofar as the rim is centered when you put the wheel in the frame. However, I noticed that the hub is actually spaced further to the left, causing difference in angles between the drive and non-drive side spokes to be greater than normal.

What I need to do, I think, is re-space the hub so that it sits further to the right, then dish the wheel accordingly. This would make for less tension differential between the drive and non-drive side spokes.

When the wheel was popping spokes, the were always on the non-drive side, at the flange.

Iowegian
01-07-08, 03:34 PM
Did you make sure all the spoke heads were properly seated in the hub? Is the tension even between the spokes (110-140 is a pretty big delta)?

Ride it a few times, then true it again. If it still doesn't hold true, I'd save the hub and chuck the rest.

TO11MTM
01-07-08, 05:05 PM
Possibly nothing is wrong with what you did... I've built a decent amount of wheels, both for personal use and for use of customers when I worked at a shop.

I ran into an AlexRim with a similar issue... Every other wheel I've built has performed flawlessly... this one had similar problems.

That's not to say all Alexrims are problematic (I've got a set of XT16s on my mountain bike, again handlaced and they've been perfect for over two years now...) but I have seen some with issues. Not sure if it was a bad heat treat on the aluminum or what... but it happens.

MrCjolsen
01-07-08, 05:11 PM
What always perplexed me was that a double walled 36 spoke wheel is supposed to be pretty bomb proof.

I'm going to re-space the the hub and re-dish the wheel and see what happens. If that doesn't work, then I'll probably chuck the whole thing (the hub isn't anything to write home about either.)

Mudu93
01-07-08, 07:08 PM
Can't say I know a thing about wheelbulding or even truing, but I had a set of DA22 rims. Made the same purchase that you did off ebay and they never would stay true and shortly after having them worked on popped two spokes about 45 miles into a 50 miler. After that I just gave them away.

MrCjolsen
01-07-08, 08:32 PM
Were they $100 shipped, for a set? And came in a box labeled "Windsor?" And came with Michelin dynamic 23mm tires?

Bob Dopolina
01-07-08, 09:55 PM
If it is an OE wheel I know Alex used to use Jung Nan spokes which were crap. They have switched to DT for quite a bit now so you'd need to look at the spoke head to find out.

Tension balance the wheel. As someone mentioned, the difference between spokes on the same side of the wheel should be slight.

I'd do that and then ride the wheel a few times to see if there is any improvement. If not I'd swap out the spokes (you have the correct length, non?) and try it again. If it still isn't working for you be thankful for the experience and chuck it. Save the hub.

MrCjolsen
01-07-08, 10:33 PM
I looked at the spoke heads. They aren't DT. I had thought of replacing the spokes, but if I did that I'd just as soon build a whole new wheel.

When I got home, the wheel was no less true than it was when I trued it during recess today. But the hub is definitely about 3mm further to left the than it is on my other wheels.

I have a few other cheap alex rims which have given me very few problems. But they are either front wheels or track wheels. Go figure. I also have a Mavic MA3 which I've been abusing for a while on my Miyata and it's stayed pretty true as well. I rebuilt that wheel the same way I did the Alex rim.

I took the wheel off my bike and put my new 32mm tire on my near-bombproof Mavic T520 wheel. It will be interesting to see what happens when I respace the hub on the DA22 rim.

Bobby Lex
01-08-08, 05:33 AM
It sounds like the problem with the wheel coming out of true is that your driveside spoke tension is not even enough. Maybe the rim is screwed up to the point that it's not possible to get the spokes evenly tensioned and have the rim round and true.

The 110-140 kgf figure is what's acceptable for the driveside spokes on that rim, but it doesn't mean you should have the driveside spokes varying that much. If you decide to go with 120 kgf on the driveside, for example, you should try and tension all the driveside spokes to as close to 120 kgf as you can. You should be able to get within 10% (or less) of that figure, with the wheel true, round, and dished correctly. Even spoke tension is very important, or a wheel will tend to go out of true often-

+1.

The recommended protocol for tensioning a rear wheel is as follows:

1. Measure and write down the spoke tension of every drive-side spoke.
2. Total (add) the tensions of all drive-side spokes.
3. Divide the total tension by the number of spokes to arrive at your average tension.
4. Compare the average tension of all the spokes with the tension of each individual spoke. The variance should never be more than 20%. (I aim for 10%, and my best wheel-build was around 3%).
5. Re-tension and re-true and repeat as necessary.

Also, although you mentioned that you stress-relieved the wheel I'm not sure that you did an effective enough job. If you properly stress relieve your wheel, you should get the same results as when you ride it for the first time.

Personally, I stress relieve by using both the spoke-squeezing method AND the lay-it-on-the-floor-and-flex-the-rim method. And I do this several times during my wheel-build, not just once.

If you do all of the above, and your wheel still won't stay true, I would suggest your rim is a lemon.

Bob

MrCjolsen
01-08-08, 09:20 AM
If it still isn't working for you be thankful for the experience and chuck it. Save the hub.

Is it economical to do that? I can get a Mavic Open Sport rim for $32. Add spokes, and $30 for a Tiagra or Deore hub doesn't seem like too much.

However, I haven't had any problems with the hub, and since I was going to re-space it, I figured I'd replace or repack the bearings anyway. It turns pretty smooth as it is.

Also, I'd like to do a rear cassette wheel build for the first time without making a huge investment before I start using nicer hubs and rims.

In other words, does a cheap hub generally outlast a cheap rim?

Can a cheap hub be made less cheap by replacing the bearings?

I guess I should start another thread at this point.

supcom
01-08-08, 10:31 AM
Spoke wind-up?

MrCjolsen
01-08-08, 11:13 AM
I'd say spoke wind up, but the familiar pinging noise when I first rode the wheel was entirely absent.

Here's a new question. What is it about a cheap rim and cheap spokes that makes a well-built wheel not want to stay true? In other words, can a good builder make a strong wheel out of crappy parts? And where does the hub fit into the equation, save for the dishing issue I mentioned previously?

cachehiker
01-08-08, 01:21 PM
What is it about a cheap rim and cheap spokes that makes a well-built wheel not want to stay true? In other words, can a good builder make a strong wheel out of crappy parts? And where does the hub fit into the equation, save for the dishing issue I mentioned previously?

I rarely reuse spokes. Although not clearly defined, it is possible that a few of yours may have been taken past their elastic limit in the past. Once that happens, they will have a tendency to continue stretching after retensioning and are doomed to break at some point.

My most bombproof wheelset was made out of crappy parts. It's the only one with straight gauge spokes and you can find a lot stronger rims than a Weinmann ZAC19 that weigh considerably less. This is the wheelset I use in the mud and snow rather than let my LX/XT/105/Ultegra hubs fill up with crap. Only thing I've noticed is that a high quality, machined sidewall, eyeleted, and welded seam rim like an Open Pro is often easier to build with as there seems to be fewer residual stresses from the fabrication process left to be "pulled into true".

Applehead57
01-08-08, 02:22 PM
I thought you would use threadlock blue not Prolink.
I've only built two wheels, but I used a medium strength threadlock not a lubricant.
My wheels stayed true (until I hit a hidden storm drain).
I could be wrong, but wouldn't lubrication encourage movement of the nipple?

Iowegian
01-08-08, 03:19 PM
Here's a new question. What is it about a cheap rim and cheap spokes that makes a well-built wheel not want to stay true? In other words, can a good builder make a strong wheel out of crappy parts? And where does the hub fit into the equation, save for the dishing issue I mentioned previously?

Nothing wrong with a cheap rim as long as it's true and round. Of course, if you want to increase the odds of getting a true and round rim, you won't buy the cheap stuff.

The strength of the wheel is limited by the lowest tension spokes since a wheel 'stands on its spokes'. If the rim isn't true you must force it so with uneven spoke tension. This will most likely either lead to some spokes having insufficent tension to 'stand' or on the other extreme, some spokes having so much tension that the rim or spokes fail (break).

As others as mentioned, if you exceed the elastic limit of steel it deforms and doesn't spring back, resulting in a permanent (rather than temporary) loss of tension in the spokes and a wobbly wheel. A good bike wheel is designed close the edge of what the material can tolerate and requires the load to be evenly distributed across the spokes to stay true. An out-of-whack rim ruins this balance and the rest of the parts just can't cope:eek:

The hub shouldn't have much effect on wheel true or wheel life. Just keep the bearings clean and greased and any decent hub should last for many 10,000's of miles.

Bob Dopolina
01-08-08, 04:42 PM
I wasn't suggesting chucking the hub. From your OP you mentioned that you were just getting into wheel building so I thought the exercise of swapping out the spokes, even if it wasn't the correct solution, would still be of value.

As I mentioned, Alex used to use cheapo spokes. I used to test wheels for them. The spokes would last me about 1000-1500k and then start to fail on mass.

Since you bought a used wheel, rode it, then rebuilt it with used spokes my assumption was that the spokes were the issue.

My suggestion is to replace the spokes. The hub and the rim could be just fine. Spokes are the least expensive option so why not start there and see if you can salvage the project.

Rowan
01-08-08, 11:36 PM
I thought you would use threadlock blue not Prolink.
I've only built two wheels, but I used a medium strength threadlock not a lubricant.
My wheels stayed true (until I hit a hidden storm drain).
I could be wrong, but wouldn't lubrication encourage movement of the nipple?

Threadlock is not a good idea. Lubrication is good... Jobst Brandt says so. That's why I don't use any lube or threadlock at all when building my wheels. It's not needed if things are set up quite well. The caveat on this is that I have been considering using raw linseed oil... it provides the lube that everyone seems to want, plus sets like a very weak threadlocker.

I think the problem has nothing to do with the way MrCjolsen has built the wheel, but definitely the components. If you have an Alex rim with those nasty spokes off, say, a Fuji (Windsor?) then you are in for an awful time. The Fuji Touring model from around 2001-02 had those terrible spokes, and so many of them broke, it wasn't funny. They were laced to an Alex rim.

Ditch the spokes for a start and invest in good ones -- DT or Wheelsmith. I would like to think it is a rim problem, but I cannot imagine how it could be... even drilling the spoke holes at the wrong angle shouldn't cause a spoke breakage at the hub.

buddyp
01-09-08, 05:11 AM
I have a similar problem right now. I noticed a crack in the rim of one of my rear wheels. Sun ME-14, 32 hole laced with DT 14ga straight spokes to a veloce hub. It was probably built in 1997. I had a similar (same rim, same spokes), but even older wheel except with a NR hub. That wheel had hardly been used at all - not long after I quit using sew-ups I switched to ergo. The rim from the NR hub still has all the anodizing on the sidewalls.

At any rate, I took the rim off the NR hub and put it on the veloce hub (left all the spokes finger tight) and took it to a LBS to have it dished and tensioned. Sat. AM the shop called and left a message that the wheel 'was beyond repair'. I picked it up last night and at first glance it looked great, but when I spun it, it was clear that while it wasn't a taco it was at least a tortilla :( Its out by a couple of mm. not usable for sure.

So my question is what would cause this to happen? The rim was fine when took it off the other wheel. Any suggestions for maybe trying to salvage this wheel?

San Rensho
01-09-08, 07:19 AM
I would definitely start with respacing the hub and getting the cassette as close to the frame as possible. The less dish a wheel has, the stronger the wheel is and the less prone to spoke breakage.

Be sure to check the chainline after you re-dish, as it will change.

Bob Dopolina
01-09-08, 07:22 AM
I have a similar problem right now. I noticed a crack in the rim of one of my rear wheels. Sun ME-14, 32 hole laced with DT 14ga straight spokes to a veloce hub. It was probably built in 1997. I had a similar (same rim, same spokes), but even older wheel except with a NR hub. That wheel had hardly been used at all - not long after I quit using sew-ups I switched to ergo. The rim from the NR hub still has all the anodizing on the sidewalls.

At any rate, I took the rim off the NR hub and put it on the veloce hub (left all the spokes finger tight) and took it to a LBS to have it dished and tensioned. Sat. AM the shop called and left a message that the wheel 'was beyond repair'. I picked it up last night and at first glance it looked great, but when I spun it, it was clear that while it wasn't a taco it was at least a tortilla :( Its out by a couple of mm. not usable for sure.

So my question is what would cause this to happen? The rim was fine when took it off the other wheel. Any suggestions for maybe trying to salvage this wheel?

They over tensioned the spokes.

Zouf
01-09-08, 09:46 AM
I would definitely start with respacing the hub and getting the cassette as close to the frame as possible. The less dish a wheel has, the stronger the wheel is and the less prone to spoke breakage.

Be sure to check the chainline after you re-dish, as it will change.

Ideally, *before* you re-dish, but after you re-space. Would be great on the educational value, but bad on the probability of throwing the wheel through a window, if you did the entire re-dish to then realize the chainline was creating a problem...

buddyp
01-09-08, 10:14 AM
They over tensioned the spokes.

Is the rim dead now or can I back off the spoke tension and get it true?

Bob Dopolina
01-09-08, 04:31 PM
Is the rim dead now or can I back off the spoke tension and get it true?

Back off the tension and see how the wheel reacts. Usually it's ok. The real test will be to get it into round, and straight, and see if the tension is fairly uniform. If it is vastly uneven (on the same side) then you know for sure it's toast.

Also, have a glance inside the spoke holes and make sure that the spokes didn't get mixed up somehow. If you see a clear difference in how much the spokes are recessed into, or sticking out of the nipples (from inside the rim) then this would also cause this problem if the tension was even around the wheel.

Mudu93
01-09-08, 07:25 PM
Were they $100 shipped, for a set? And came in a box labeled "Windsor?" And came with Michelin dynamic 23mm tires?

Yes those are what I had.

MrCjolsen
01-09-08, 08:38 PM
I would definitely start with respacing the hub and getting the cassette as close to the frame as possible. The less dish a wheel has, the stronger the wheel is and the less prone to spoke breakage.

Be sure to check the chainline after you re-dish, as it will change.

I talked to a mechanic at a fairly high end shop (Bicycle Business in Sacramento) and he said that a few mm would not make a difference.

I put the wheel on my stand last night and discovered a small dent on one side where it had gone out of true. So the wheel took a hit at some point.

I generally don't sweat chainlines on derailleur bikes as long as they are reasonable. What I'd actually like to do is have it so all my rear wheels have the same chainline so I can swap them between bikes effortlessly.

I bought a Mavic Open Sport rim last night. I guess my problem would be solved if I put it on the old hub. But the greedy little boy in me wants another track wheel. And the skinny Open Sport / MA3 rims have a nice classic look that's real nice on fixed gear bikes.