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Edit: Wazgilbert posted some useful information about the "short" wave washer here which undermines my argument quite a lot. I thought there was a "bad batch" of wave washers out there causing low preload and hence a tendency to click/creak. I thought I had enough evidence to make it worth writing this post. But Wazgilbert's measurements seem to show that I'm wrong. So I don't know what's going on. You might want to ignore much of what's said below since I now have no constructive suggestions. Wazgilbert is going to measure a few other washers, I will update this post again if he comes up with any new information. Sorry if I've wasted anyone's time or money.
If you bought a Campagnolo Power Torque crankset in 2012 you may have a defective wave washer which may cause it to creak or click under load (eg while pedalling out of the saddle). You can read the full thread here, but it's very long and has an unhelpful title. This posting is just a simplification to warn you.
This thread is not about Ultra Torque cranks. It is only about Power Torque which in 2012 is used on Veloce, Centaur & Athena. Earlier versions of Veloce, Centaur and Athena (pre-2010 IIRC) used Ultra Torque.
What is the noise?
A creak or click once per pedal revolution when the crank is under load, eg when climbing out of the saddle. Creaks and clicks have lots of sources, your click could be an indicator of a different problem, you should check out alternatives (pedals, headset, quick releases, etc) before reading further.
With the "Power Torque click", in my case, removing the crank, adding more grease to the bearings and cups, and replacing the crank will silence the click for tens of miles. Then it comes back.
What is the cause?
I believe that the problem is caused by a weak "wave washer" which provides the "preload". Other posters on these forums agree. The preload stops the crank moving from side to side when you pedal. The wave washer is the big spring like thing which fits between the left hand crank arm and the bearing in its cup. If this wave washer is too weak, the crank moves from side to side, especially when you are pedalling out of the saddle. This side to side movement gradually pushes the grease out, and the click begins as the un-lubricated parts rub together.
I believe Campagnolo changed the design of the wave washer in spring 2012 (I am not sure of the dates). I believe the "old, good" wave washer was about 5 mm high, and very strong. If you squeezed it between thumb and forefinger, you would hardly be able to move it. The "new, bad" wave washer is about 10 mm high, a bronze colour, and is so weak, you can squeeze it quite flat between thumb and forefinger. I have put photos of the "old" and "new" wave washers at the bottom. The "old, good" is on the blue frame, the one in the guy's hand, with the Campagnolo logo at the top. The "new, bad" washer is on the black frame (my bike).
I have spent 3 months (and counting) trying to get Campag's UK representative to believe me that the wave washers are bad. I still don't have a resolution, but Italy is now involved so there is hope.
I am not just making stuff up. Campag Italy gave me the production specification on the wave washer. The specification says it is supposed to take 17 kg to squash it flat. My wave washers take about 5 kg to squash flat - they are much, much weaker than the specification. You can read the big thread if you want more details of my diagnosis.
How do you find out if you are affected?
I would guess that if you bought your crank in 2010 or 2011 you are not affected.
The most reliable way is to pull the crank arm off (good luck with that*) and take a look.
If you don't want to do that, a simple but maybe less reliable way is to put both your thumbs on the big crank bolt on the left hand side. Wrap your fingers around the chainstay and the down tube, and push with both thumbs quite hard. If the crank moves a tiny bit (a fraction of a millimeter) sideways, you may have a "new, bad" wave washer. You may also hear a distinct crunch/click when you do this. When you release the pressure, the crank may spring back, or it may "stick" until you pull it back by hand, or turn the pedals.
I expect that if you have the "old, good" wave washer you will not be able to move the crank with your thumbs. But you might be able to move it if you exert more force, for example by squeezing the crank arm and the chain stay with your fist. It's not whether you can move the crank that matters, it's how much force it takes. Thumb pressure is less force than squeezing the chain stay.
How many people are affected?
I have no idea. I have found 2 or 3 on the Internet who might be affected. Plus me. The problem seemed to surface in summer 2012. Some people may have "new, bad" wave washers but a silent crank - for some people the preload from the "new, bad" wave washer might be adequate.
The Campagnolo UK guy bought some wave washers at retail in late September 2012 and they were still the "new, bad" kind. So I suspect that all the washers in retail are "new, bad" ones, in the UK at least.
What can you do?
If your crank is silent, don't worry
If you get a click or creak, check out all the other possibilities first, there are some good troubleshooting guides on the Web.
If you were planning to buy a Power Torque crank, maybe you should hold off until this is sorted. Power Torque is a really bad system IMHO*, I would suggest you think hard before buying it.
If you bought Power Torque in 2012, you have a click or creak once per pedal rev when out of the saddle, and you are sure the crank is the cause....
- please post on here
- contact your Campag service rep. If you are in the UK that is Velotech, Google 'em. Velotech is aware I have a click/creak, but for some reason Velotech is still trying to blame my frame, even though Velotech has actually measured that the wave washers clearly do not meet the Campag specification. (no, I don't understand either)
- what you want is an "old, good" wave washer, about 5 mm tall, probably from 2011 stock. Your LBS may have one? Or your Campag rep?
Maybe I am making this all up. Maybe the wave washers are fine. YMMV. But I thought it was worth posting to inform you, if you are suffering the same problems as me.
* Power Torque IMHO is not great. Installing the crank is really easy. Removing it is really difficult. You need a special "puller" to do it. The Campag recommended one is really expensive. You can buy a cheaper one, but it might require "modification" with a file or Dremel. Even then IMHO there is a good chance you will scratch the cranks. Particularly with carbon cranks. It's nasty. By contrast Campy's Ultra Torque system looks really nice, though I have not used it. One simple bolt and the thing just falls apart.
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Originally Posted by cs1
