Trueing Wheel Dilema

[dfvcad]

Here is the scoop, I recently finished riding the Tour of Laredo, well that's what my three cycling friends and I call it. We rode 429 miles in 3.5 days. On the first day I got a flat after about 115 miles riden so i pump up my rear tire with the CO2 but I only got about 90 psi into the wheel, so we continue riding the last 30 miles but I was feeling moderate rolling resistance on the rear and the road was not completly glass smooth. I get to the hotel check the wheel and it had mild side to side wobble. I was able to ride the other 300 miles on the wheel with no incident of rubbing or problems. I never hit any potholes.

Know I decide to take the rear wheel (American Classic Sprint 350) to the only LBS in town to have the wheel true and the guy tells me that he is having problems getting the wheel straight and has to check all the lengths of the spokes to see why its not holding, but in the process now the truing went from $7-8 to nearly $35 for a simple truing job. This wheel never gave me trouble for the past 1900 miles. Why would this bike shop guy/owner need to do this type drastic work? When I purcahse my Orbea in San Antonio,TX the wheel was out but it was corrected then in Oct 04 and since then no problems. Any suggestions, what could be going on. If feel that I am being taken for a ride on this one.

 

[jerryz]

Here is the scoop, I recently finished riding the Tour of Laredo, well that's what my three cycling friends and I call it. We rode 429 miles in 3.5 days. On the first day I got a flat after about 115 miles riden so i pump up my rear tire with the CO2 but I only got about 90 psi into the wheel, so we continue riding the last 30 miles but I was feeling moderate rolling resistance on the rear and the road was not completly glass smooth. I get to the hotel check the wheel and it had mild side to side wobble. I was able to ride the other 300 miles on the wheel with no incident of rubbing or problems. I never hit any potholes.

Know I decide to take the rear wheel (American Classic Sprint 350) to the only LBS in town to have the wheel true and the guy tells me that he is having problems getting the wheel straight and has to check all the lengths of the spokes to see why its not holding, but in the process now the truing went from $7-8 to nearly $35 for a simple truing job. This wheel never gave me trouble for the past 1900 miles. Why would this bike shop guy/owner need to do this type drastic work? When I purcahse my Orbea in San Antonio,TX the wheel was out but it was corrected then in Oct 04 and since then no problems. Any suggestions, what could be going on. If feel that I am being taken for a ride on this one.

Are you being taken? WHo the heck knows? On the other hand he may just be looking for a way to charge you for the time he spent on a very difficult wheel. Now the odds that the spokes aren't the smae length? lol that is sort of funny. If he is right then he's worth the money. If was wrong then he shouldn't be able to charge you for a WAG.

 

[artmichalek]

It's highly unlikely that the issue is spoke length. Most likely the rim was bent when you bought it. If a rim is significantly out of plane/round, it's nearly impossible to get it trued with the right spoke tension. Did you buy the bike new or used?

 

[Dondare]

It's highly unlikely that the issue is spoke length. Most likely the rim was bent when you bought it. If a rim is significantly out of plane/round, it's nearly impossible to get it trued with the right spoke tension. Did you buy the bike new or used?

I had a new wheel that was true but the spokes were all different tensions. It was OK for a year, but when it did develop a wobble I was told that the rim wasn't round and couldn't be trued. The original builder had put excessive tension in some spokes and left others slack, but the bloke in the shop wasn't prepared to do that. So I bought a new rim and he rebuilt it with new spokes on the original hub. What he told me made sense, I had noticed the tight and slack spoke already and I do not think he was ripping me off.

 

[Weisse Luft]

I had a new wheel that was true but the spokes were all different tensions. It was OK for a year, but when it did develop a wobble I was told that the rim wasn't round and couldn't be trued. The original builder had put excessive tension in some spokes and left others slack, but the bloke in the shop wasn't prepared to do that. So I bought a new rim and he rebuilt it with new spokes on the original hub. What he told me made sense, I had noticed the tight and slack spoke already and I do not think he was ripping me off.

The problem the LBS is having is due to the rim and spoke combination. IIRC, the drive side spokes are 14/15 while the non-drive are 14/17. As such, the spoke tensions are vastly different as well as the relative turns required to true the wheel.

A good mechanic should be able to true the wheel. This is an art not many have.

I built my American Classic wheels from components (don't ask me where I got them), the CR350 rims, 28 rear, 24 front and the micro front with 225 gram rear hubs. 14/17s all around, radial drive side, 2 cross non-drive. No problems, save a broken nipple. When the nipple broke, I had to start over from zero tension on all the spokes.

Send me an IM. I can fix it for you for far less. These wheels respond better when the spoke tension is relieved during adjustment. This is done by placing a load on the rim around the spoke being adjusted, simulating normal loading. The spoke is much easier to adjust when this is done. Most bike shops know nothing of this as they ascribe to the faulty theory that the hub "hangs" from the spokes.

 

[DiabloScott]

The problem the LBS is having is due to the rim and spoke combination. IIRC, the drive side spokes are 14/15 while the non-drive are 14/17. As such, the spoke tensions are vastly different as well as the relative turns required to true the wheel.

Drive-nondrive spoke tensions are different only because of the dish, different spoke diameters have no effect on tension- any diameter spokes on either side would exhibit the same disparity. Thinner spokes may stretch more but that would only be an issue on the initial build and wouldn't have any effect after stress relieving.

Most likely is that the rim was bad before he got the wheel and it was tweaked to make it come into true and now the tweak is failing because of improper tension caused by the tweaking - completely normal that it would take a while for this to show up. I have no idea why the mechanic wanted to check spoke length - that wouldn't be any issue unless they either wouldn't reach from being too short (not the case here) or were bottoming out on the nipple threads from being too long... and that would be obvious. I think the mechainc is a putz and the OP needs a new rim.

 

[Weisse Luft]

Drive-nondrive spoke tensions are different only because of the dish, different spoke diameters have no effect on tension- any diameter spokes on either side would exhibit the same disparity. Thinner spokes may stretch more but that would only be an issue on the initial build and wouldn't have any effect after stress relieving.

Most likely is that the rim was bad before he got the wheel and it was tweaked to make it come into true and now the tweak is failing because of improper tension caused by the tweaking - completely normal that it would take a while for this to show up. I have no idea why the mechanic wanted to check spoke length - that wouldn't be any issue unless they either wouldn't reach from being too short (not the case here) or were bottoming out on the nipple threads from being too long... and that would be obvious. I think the mechainc is a putz and the OP needs a new rim.

That wasn't what I was saying. The different gauges of the spokes makes truing more difficult because the more elastic non-drive spokes require many more turns to effect the same lateral displacement. Even when considering the different bracing angls common on hub/rim combinations...and....

The American Classic rear hub design also has the non-drive flange closer to the center, making spoke tension more balanced.

Without visual rim damage, most rims CAN be trued despite having minor waves when untensioned. In fact, most rims once laced and stress relieved, will show definite waves even when carefully detensioned.

My experience building three sets of these wheels using THE EXACT SAME RIM AND HUB COMBINATION is more than enough to say I know what I am talking about.

 

[DiabloScott]

My experience building three sets of these wheels using THE EXACT SAME RIM AND HUB COMBINATION is more than enough to say I know what I am talking about.

Maybe so, but you didn't say it very well. The below statement is completely wrong:

"the drive side spokes are 14/15 while the non-drive are 14/17. As such, the spoke tensions are vastly different"

Also, requiring extra turns to effect the same tension is clearly not the cause of the OP's trouble. The trouble is the mechanic can't get the wheel into a true state with balanced tension - that's either a rim problem or a really bad wheel mechanic.

I assume we don't disagree on the "wrong spoke length" BS.

 

[dfvcad]

artmichalek

The bike was brand new and it came with Mavic Equippe wheelset. I was given an option of swaping out for the AC 350 which had a Dura Ace cassette. I went with the AC because its much lighter and the wheel spins up much faster.

 

[dhk]

artmichalek

The bike was brand new and it came with Mavic Equippe wheelset. I was given an option of swaping out for the AC 350 which had a Dura Ace cassette. I went with the AC because its much lighter and the wheel spins up much faster.

No rear wheel is going to last forever. Don't know the specifics of the AM 350 Sprint, but in general, lighter wheels aren't as durable as heavier wheels. A "sprint" wheel sounds like something intended for race-only use, not for multi-day tours.

The advantage of lightweight wheels for the average rider is way oversold, IMO. The work required to spin up any wheel just isn't that much, compared to the work required to accelerate your bodyweight. (You can check this yourself by spinning up your rear wheel with the bike on a stand). Unless you're worried about the last few seconds of a finish line sprint, and can afford to replace wheels often to win races, durabilty is the way to go.

A lightweight wheel has to be very carefully designed and built to hold up, and as a result, a quality lightweight wheel isn't cheap. The old saying is: "lightweight, long-life, or low-cost....pick any two."

At 1900 miles, I'd probably toss this rear wheel and get something more durable.