ultimobici wrote:Bridgeman wrote:Calnago, thanks for your very kind words. Yes, you are correct, "the chainlink outer plates ride on the ridge of the 11tooth cog that also acts as the spacer between it and the 12 tooth cog". The outer plates of the 11 tooth sprocket are riding on that ridge, rather than the rollers riding in the valleys between the sprocket teeth. I have many many used sprockets showing evidence of this, and some time ago I began modifying the sprockets to provide clearance which yielded new life to the cogs.
Because of the geometry of the Missing Link end plates, the elongated portion, this only exacerbated the problem.
I am still open to the idea that I could be overlooking something, but until that happens I think Campy needs to address this issue. Chains should not be rolling on their end plates as it is not the most efficient way to utilize them. All other cogs have proper clearance, as the chain rollers are engaged with sprocket valleys.
How is this an issue Campagnolo need to address? KMC is the source of the issue, not Campagnolo.
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I understand your point, and agree that it is a valid one. There are, in my opinion 2 distinct issues at play, and I see I haven't been clear about delineating them.
My Issue 1. The KMC link potentially can become problematic when used on Campagnolo 11 tooth sprocket.
Since this is not the responsibility of Campagnolo, it would not be appropriate for them to address this potential issue, particularly when it is in their best interest to insist that their pin coupling method be used. Completely understandable.
My Issue 2. Under load, the Campagnolo chain (without the KMC link) makes contact with the 11 tooth sprocket ridge.
In my case this contact has caused problems with chain skipping. This has been a problem for me for some time now, well before I began the use of the KMC link.
Update; I now believe I understand what might be causing my skipping issue.
When the chain is in the 53X11 position, it is at an angle. Under load, the chain is being pulled inward, towards the ridge side of the cog, an angular moment.
If there was no angle, and both the 53 and 11 were in the same plane then this normal force condition would more than likely not result in skipping under load.
As mentioned, I have many cogs that clearly show wear marks as a result of this contact. When the chain end plate is making contact then the chain it is not permitted to fully seat into the valley of the 11 tooth cog, causing it to wear prematurely.
In every case when I have made a simple modification for clearance on the 11 cog the skipping was no longer an issue.
Now, introduce the KMC Missing Link. Because of its unique end plate geometry, this exacerbates this situation. But when I modify the cog performance is restored.
I should re-qualify the condition of my 3 cassettes. I claimed they were new, they were not. They have approximately 180 miles on them. All 3 have very slight contact marks in the inner ridge of the 11 cog. The mileage is so low I just considered them to be new. The chain is new however. For reference, chain cleaning and frequent lube is an obsession with me. Usually after every ride.
Photos coming soon.