First off I don't know anything about building up a wheel. Yesterday on a group ride my rear wheel came out of true (very bad) and I don't think it was because I hit anything, very good roads at a moderate pace. Took the wheel in and had a mechanic true it up - I watched it seemed like he did a great job.* On todays ride the wheel again came way out of true and I know I didn't hit anything and was on some of the nicest roads I've ridden.

I've broken spokes before and never had the tire go woefully out of wack so quickly. There were so many spokes that were incredibly loose. 

Had a spoke wrench with me tried to use my brakes to tighten and true the tire along side the road (too far to walk) but none of the spokes would keep their tightness (over time) and I wasn't going to oven tighten them - unsure what's going on out on the side of a road. 



So any insights why a perfectly trued tire would come out of true after riding for less than forty miles? Again I know today and yesterday I didn't hit anything including potholes. Thanks for any advice, jeff 



p.s. the road bike /wheels are less than a month old

Just being true is not sufficient.
The tensions of the spokes must also be even and close to the same, all the way around each side of the wheel.
(I shoot for within ~10% when building a wheel).
I'm suspect this was not the case after the the mechanic worked on it, even though the rim was true.

iLots of things that can go wrong, but one thing to consider in your case is the possibility that a few nipples are stripped. You align he wheel and the spokes simply pull out throwing it off anew.

Given the age of your bike, I'd be surprised, but OTOH I'd check anyway especially if the spokes are somewhat short and you cant see the ends near the top of the nipple.

Other than that it could simply be a poorly built wheel, you could have a riding style that's hard on wheels, putting lots of side stress on them, or any of a number of subtle problems which can't be diagnosed over the internet.

Improperly built. Improper tension, excessive tension variation. Rim/Spoke/hub combo not appropriate for rider weight/conditions etc. etc. It's likely it's a crappy machine built wheel that was never made good on a new bike build. Not that uncommon.

Please tell us what bike/what rim/hub/spokes combo you're riding. And you're weight + loaded weight.

Did the mechanic use a tensionmeter to make sure the spokes were relatively even in tension?
The only reason a wheel would fail under normal use like that would be because the spoke tensions were all out of whack.
If the bike is only a month old, demand a replacement rim and spokes built up properly. Or a replacement wheel from the manufacturer.

not enough tension, too much tension/cracked rims or spokes were not stress relieved.
check for cracks in the rim or hub.

I think it's more of an issue with not enough spoke tension and spokes there were not stress relieved.

Based on your description, that wheel either wasn't built well/correctly, or spec'ed correctly for your weight. Perhaps a bit of background for your reference:

A wheel is a pre-stressed structure. A corollary of that is its weight carrying capacity is a function of the spoke tension of the unladen wheel. Essentially, the bottommost section of the rim deforms as it is loaded and the tension of the spokes associated with that rim deformation is lowered. So, if your spoke tension wasn't high enough for the wheel's intended load to begin with, as the wheel is laden, the tension of the bottommost spokes will drop to zero. As that happens, the nipples will be loose and can thus rotate freely (from road vibration) and misalign the entire wheel.

This mechanism can also occur if the spoke tension is not uniform across the wheel. The lower tensioned spokes are more likely to loose all their tension and suffer the same misaligning issue as an overladen wheel, because essentially, the section of wheel associated with those spokes are overladen.

Check out Jobst Brandt's The Bicycle Wheel for more details.

I'd think if the spokes were properly tensioned to begin with, even if they weren't stress relieved originally they'd be pretty close to being stress relieved after a month of riding so that the second truing would last a bit longer. After all, the wheel stayed true for a month.

I'm voting for "badly undertensioned ALL spokes" from the beginning, the spokes have worked themselves even looser, and that the mechanic didn't fix it.

Thanks for the insights, the wheels/hub are Alex ALX 200 and I weight 185.

"If the bike is only a month old, demand a replacement rim and spokes built up properly. Or a replacement wheel from the manufacturer."

This is my next question after todays ride on a very wobbly tire is it likely that it been damaged beyond repair whereas I should ask for a replacement on such a new wheel? Or can it be trued back to good condition - I didn't have a choice I was too many miles from home

thanks again for the help. jeff

if this was a new bike there is no reason why the shop should not rebuild this wheel or replace it. the mechanic knows you are having trouble and they should take care of you.

A wheel that goes that far out of true has a rim with comprimised strength. There's no excuse for you to settle for that with a month old bike. If the wheel was defective when you bought it - like it sounds like it was - the shop should honour the manufacturer's warranty and not just try to cobble it together into a barely usable state.

The Aluminum rim is probably warped and may require abnormally high tension from a few spokes to remain true. I'd contact the mfr or dealer for a new rim, spokes, and nipples. The shop or mfr should also pay for the cost of building the wheel.

I will never build a wheel with less than 32 spokes. Stick to 32 or 36 hub with 3x lacing.

To get a lasting deformation in a rim you have to bend it way out of plane, IME something like 6-8 inches. I can't imagine how anyone would be able to do that while JRA. If you havent got a spoke tensiometer you can check this by slackening all the spokes and see if the rim stays flat or not.

So, while odds are that the rim hasn't taken lasting damage I think you have the right to expect more from such a new, store-bought bike. I'd ask for a replacement wheel.