ADAM31

LBS says it is safe to ride…I am looking for advice on how safe is it. Rear wheel
So I knew something was wrong, I had heard a ticking noise from the area. The noise however was only there in the first 20-25 minutes then the rest of the ride was quiet. I decided to get the chain swapped out and gears adjusted but the noise continued and that’s when I discovered the cracks
DT Swiss R470 disc wheels bike is Specialized Tarmac

easyupbug 

Get another LBS.

Fissile

Seconded.

ADAM31

it’s not that easy where I live I would have to drive an hour to the another one. They are the only ones in the county unfortunately

easyupbug 

I probably should add that is a fatigue crack which is a stress riser concentrating the stresses on the rim at the end of the crack (the sharp edge) and can move quickly. You have exceeded the fatigue limit of the rim and concentrating the stresses on the rim with each wheel rotation.

Fissile

There are other options. If the hub is worth saving you can rebuild the wheel yourself. When I was a kid I rode dirt bikes. This was back in the day when most rims were steel, and tacoed wheels were common. The only way I could afford to keep riding was by learning the alchemy of wheel building. Seriously, it's not that hard. I was doing it at 16 and I'm no genius...ask anyone who knows me for confirmation. Your other option is to order a new wheel or wheel set.

ADAM31

I think the wheel is under warranty but the LBS is not working to hard to replace it I took it in last week but have yet to hear anything

_ForceD_

I have a rear wheel that got an identical crack a couple of years ago. Just on a single spoke hole of a double-walled rim. I sort of inadvertently discovered it while cleaning chain lube off the rim. And, as you might think the wheel wasn’t out of true. So, I immediately ordered a replacement wheel. It was about a week or more before the new wheel arrived. In the meantime, I rode the bike a couple more times. The wheel remained true, the crack never got bigger. So, I thought “I’ll keep riding it until it pulls through more, and the wheel gets out of true. That was 2+ years ago and I’m still riding on it. — Dan

CAT7RDR

When my Fulcrum 5 developed these stress fractures on the spoke holes, I also received the pinging sounds.
If you listen closely, the pinging sounds like, "Replace me fool!" only in an incessant rhythm.

veganbikes

Yeah find a different mechanic, I am sorry that shop is not doing right by their customers. It is always quite sad when I hear stories like this granted we haven't yet heard the other side of why they thought a cracked rim is somehow safe when anyone could see it really isn't, While you could get lucky and it will hold and no issues you don't want to be around if it does fail on you while riding.

I would consider talking with the owner of the shop and asking them their opinion on the wheel and hopefully they will say no get a new one and then explain the situation of the previous person's view on the wheel and have them correct it. Nothing crazy or sorted just a hey just want to make you aware.

At my shop I will not tolerate unsafe stuff like this at all. Safety has to be of number 1 priority even as a business. Sending someone out on an unsafe bike just to make a buck is just wrong on so many levels. I would rather refuse a service and explain to a customer in a polite manner that hey this is what your bike needs to be safe or you need a new frame I am sorry we cannot work on this. I don't want people getting hurt out there. Also if I can fix someones brakes and it take 5 minutes I can write that off for a mechanic and just let the customer know what happened and that is was free maybe in the future when you get back on your feet pay it forward to someone else.

ADAM31

it was the owner of the shop who said it was rideable. Getting new wheel next week

veganbikes

Yowch, I wish that guy was more well versed in bikes and safety. I am guessing if all is true and correct that they just don't care or have really bad fingers and eyes.

ADAM31

well here in the north west not many options

veganbikes

No understood but that person needs to rethink things and get some more knowledge on what they are doing again assuming everything said was correct and true (and not calling you a liar but I do not know you and haven't seen the second side of the story).

It is sad when there are people in our industry that make reckless decisions on safety. Admittedly yes I can be overly cautious but I would rather be overly cautious then cavalier and see another person hurt. Having seen enough actual incidents and heard enough stories that I want to keep people safe.

bboy314

Wow. Was it safe to ride, as in, “you’ll be ok for a few rides while we order you a rim”? Or safe, as in “nah, you’re fine, no warranty issue here”?

Pratt

Then the LBS will be happy to swap you a new rim for that one.

KerryIrons

You guys are way over the top on this. Yes, the rim is failing and I sure wouldn't go tearing down a mountain with that crack in my rim, but I have ridden many miles on rims with cracks like that and sometimes it takes several 100 miles before the spoke actually pulls through. You get plenty of warning before that as the wheel goes out of true.

easyupbug 

I am sure everything you say is true for some but I would not not want my daughters or anyone else who would not know what they have gotten in to taking their bike to that shop and being told "LBS says it is safe to ride".

smd4

When asked to describe the ultimate end result of something like this, folks here can’t imagine the progression of events leading to failure. They can only envision smooth riding one minute, and hospitalization and death the next.

drlogik 

The wheel is compromised and the likelihood of repairing back to "good-as-new" is probably slim. Is it really worth a broken arm to save $200 bucks if it does fail? If it were mine, I'd by another wheel.

phughes

Did the shop set up your wheel? It looks like the spoke was not torqued properly. It looks like it was overtightened causing it to fail.

Russ Roth

Did the owner give you any stipulations as to how to safely ride it? He isn't strictly wrong though from a customer service perspective he's also not right. Plenty of people ride home on a wheel with a busted spoke which this situation isn't dissimilar to if its just one spot that hasn't even broken yet. I've even had to ride home over 20 miles with 3 broken spokes which wasn't fun and required bending the wheel to make it fit through the stays. I've seen customers bring in bikes with zero clue they had a busted spoke and others deciding that the wheel didn't feel right and needed adjusting but they'd actually had 4 or 5 spokes snap.
However, it would be adding a stipulation like don't try to use it much, keep the speed down to normal pedaling speed even on the downhills and only till the wheel is replaced asap. Real customer service, and more honesty, would be saying the wheel shouldn't be ridden, it needs to be replaced, and if this is a warranty issue and you don't have another bike, loaning you a wheel till the new one comes in. If this was my bike, and my only one, I wouldn't hesitate to ride it on the local bike paths at a fitness pace, but I'd also already have a replacement coming.

Duragrouch

From my post in thread "cracked spoke holes", their's was a disc hub:

Disc rims have less spoke problems due to growth in diameter due to brake heat (I've popped spokes on 20" aluminum rim brake rims on long descents where braking was required), however disc hubs do pull on spokes hard too. Not sure which is worse.

On my old road bike, no discs, flat land so light braking, smooth roads. But I would wear out a set of rims via a crack at a spoke hole in three years with about 5000-7000 miles per year, 2 sets. Then I bought a set of double socketed rims to spread the load between inner and outer walls, so reducing the stresses by more than half. Each 10% reduction in stress roughly doubles fatigue life, assuming certain fatigue curves. So 50% reduction is 2^5 = 32X increase in fatigue life. That was decades ago and I've yet to wear out those rims. I was commuting in winter and wanted to use a cheaper set of freewheel rims, then one crack at a spoke hole. I took a 30 caliber boat-tail hollow-point match bullet, so solid copper base; I measure the depth between the inner and outer rim walls, then add the width of the flange I want, and measure up from the base of the bullet, and cut the tip off there with a hacksaw, then hold the bullet with pliers and heat with torch to melt out the lead. I drill the base to fit the spoke nipple. I use a plumbing flaring tool to flare the open end about 45 degrees, at where my measurement tells me will be the transition to the inner wall. I place it in the rim hole, install the spoke and nipple and tighten until just contact with the rim, no tension. Holding the rim, I use a punch and hammer to flatten the flare down to flat on the inner rim all the way around. Then I tensioned the spoke up and trued the wheel. I rode that rim for thousands of miles and still have that wheel as backup wheels. Socketed rims are bombproof. Adding a socket, even when there are cracks at the nipple exit, still holds, because the flare has SO much more area than the original nipple seat. Sockets add rim weight, that's the only downside. What's my name?

(newly added here): You should replace the rim or wheel. If you want to keep using the rim, at least put under the nipple, the widest stainless steel washer that will fit inside the rim, to spread the load, that makes it nearly impossible to pull through, however if the nipple is at an inner "point" and the outer wall has a huge access hole, that may be impossible. A fix like I described above worked, but most don't have the ability to fabricate.

79pmooney

I never thought about aluminum rims expanding on rim braked downhills. Makes sense. Also never heard of spokes popping because of that expansion. It does bring to mind the advice of years ago of keeping spoke tensions well below allowable max for the rim and hub flanges. I've never been a fan of max tension spokes. This is another reason I'll stay off that band wagon. (My primary reason- very tightly laced wheels can go quite out of true with spoke breakage. I like the idea I can bring the bike to a stop still upright after one or more spokes are gone.)

Duragrouch

It's a confluence of bad: Aluminum has a high coefficient of thermal expansion, small diameter rim (20"), so less heat sink, and short spokes, so less elasticity. In my case, also add only using rear brake on that descent, because front rim sidewalls were more worn and I was trying to baby that. A particular small wheel bike company hypes their 20" wheels as "stronger"; Sort of. Stronger rim "hoop strength", so less likely to dent from impact. Short spokes are more rigid, but you don't want that, you want longer and more elastic, that is the driver for double-butted spokes, thinner diameter in the middle, away from bending loads on ends.