Hi there,
First of: I am not asking whether these are safe or not. I have already contacted the vendor to ask whether they or DT Swiss will handle the warranty claim.
My problem: After just cleaning my bike for more or less the first time this winter (I did clean the drivetrain religiously), I noticed cracks on my rear rim around the spokes. The cracks look like my aluminium fatigue cracks. I would just like some guesses as to what could cause this / how I can avoid it in the future.
- The wheel is a DT Swiss G 1800 SPLINE® 28" rear wheel
- The wheels are 1 1/4 years old (in Germany we have 2 years of "Gewährleistung").
- Out of the box they were very true and stayed like that until recently. Spoke tension felt absolutely normal, so I didnt mess with it.
- After noticing the cracks I also noticed a very slight wobble, but nothing major. Likely from the reduced spoke tension caused by the cracks.
- I weigh 100kg, the bike weighs 15-20 depending on gear for my commute. The wheel's rated weight capacity is 130kg.
- I have had this happen before on cheap Cube OEM wheels, which is why I bought the higher rated DT Swiss ones.
- I ride around 6000km per year on the bike, a lot of which is gravel. I also ride during winter and in snow but not as much as in summer.
- I have not had a crash on these wheels and they have no dents whatsoever.
- The bike lives in our apartment buildings parking garage when not in use.
- I ride at around 200-250W most of the time.
Could I be actually better off witching to carbon, since it doesnt fatigue?
by victoryz90
10 Comments
Well, you certainly thought about many of the aspects of the wheels. A few observations on your comments.
1. Clearly, you’re aware that cracking is a fatigue issue. It’s cyclic. You are a bigger rider. It’s possible the spokes were under-tensioned. Thus increasing your R ratio.
2. DT is known for stainless steel spokes. Extruding aluminum rims is not difficult. But I’m a believer that you let the manufacturers stick with what they’re good at. It’s possible their quality control isn’t good since they’re sourcing out the extrusion. Or they bought a machine to do it and still haven’t made it correctly.
3. I wouldn’t say that carbon doesn’t fatigue and crack. It fails catastrophically.
Almost certainly DT Swiss will replace it with no questions asked.
This kind of problems are common with cheap wheels, but DT Swiss doesn’t really fall into this category. The rim these wheels use is the DT Swiss G 540, which is a medium-priced rim with good reputation.
It looks like fatigue cracking to me. You do high mileage with high load. If these wheels have done 7500km loaded to 115-120kg in rough conditions I’d consider this reasonable wear and tear. I don’t think they have failed too soon given the duty cycle (no pun intended).
When same thing happened to me I suspected that it was from the wheel bumping into holes in the road.
I also destroyed the rear wheel like that, and I only weigh 80 kg. The solution was to build custom wheels with **DT Swiss 511 Enduro rims**—totally overkill, but you could ride those rims down a flight of stairs without tires and they’d still hold up.
This is just my personal opinion, don’t have to be true:
Those pricey parts are not worth the money.
I am riding the cheapest Shimano set WHR501 bought few years ago for like $100, I weight over 110kg, I have panniers mounted and at least once a week I’m making bigger groceries so at least plus 10kg. They wheels made over 15k km on gravel, road and sometimes I ride this bike like a cyclocross. And there is no sign of wear on them. I don’t even service the hubs, because it’s cheaper to buy them new again than service them at LBS annually.
At the same time, your DT Swiss worth twice as my whole bike are toasted.
It happens. There is a warranty for a reason and you are using it. As much as I love Carbon wheels, in your situation, I’d say you have the correct wheels. Think of it this way, you are paying more for longer lasting wheels. If the warranty is needed, this is why you pay more. They are great wheels. Even the toughest wheels hate potholes etc.
I would also suggest at least wiping down your wheels just to check for this since it has happened a couple of times. I am close to your weight and I do this check regularly on all of my gravel and road bikes.
I’ll address the question about carbon. My MTB has carbon rims and after a few years the rear rim developed a crack. I sent Reynolds a photo and they said, “lifetime warranty, we don’t make that rim anymore so pick any rim in our catalog and we’ll mail it to you.” I did, they did, I rebuilt the wheel on the new rim, no problems since. That was several years and thousands of miles ago.
The moral of the story is that any rim (or frame, or any other bicycle part) can fail. Carbon, aluminum, titanium, steel, whatever. Good on you for inspecting it and noticing before you got hurt.
I had similar issues and I needed a stronger rim. I got a BMX rim, the Sun Rhynolite, but I don’t know if that’s available in Germany in the rim size you need. However DT Swiss makes very strong touring bike rims, like the U623, which can carry 180kg. That could be a very safe option for you.
I have the same wheels and they are incredibly reliable, never had any issues, three years on my gravel bike probably 10,000 km on and off road. Very unusual to see this. I would try for a warranty claim.