Small derailleur sprockets

On Tuesday, February 24, 2015 at 7:10:01 PM UTC+1, David Scheidt wrote:
Lou Holtman wrote:
:I just use 9 speed chains. First Sram PC9something and now as an
:experiment a Campa C9, which is definitely more durable. I could use a
:beefier chain, but I have to have already 9,10, 11 speed chains in stock
:for my other bikes so I use the 9 speed. I tried once a really beefy
:and really heavy chain for a track bike because I had issues dropping
:the chain in a bumpy curve with my singlespeed. That was because I used
:a chainring and a single cog meant for a derailleur system with bent
:tooths, half tooths to improve shifting. I learned the hard way that this
:is a no go for a singlespeed and gearhub bikes, so now I use a cog and a
:chainring with straight tooths meant for singlespeeds. The track chain
:was very noisy even after aligning the chainring and cog accurately. A
:derailleur chain runs very silent. The limited lifetime is no problem but
:everytime I hear people saying the the fact that the straight chainline
f a singlespeed and gearhub bikes increase the lifetime I mention that
:that is not my experience. Even the beefy and steel cog of the Rohloff
:hub wears with a worn chain and the chain wears as quickly as the same
:chain on a derailleur system. The influence of a little cross chaining
n the chain wear is insignificant. Because you only have one cog and
:chainring you don't get into trouble with a worn chain as long as you
:can adjust the chain tension. If you run out of adjustability you have
:to replace chain, chainring and cog though. I replaced chains on Dutch
:citybikes the were stretched almost 2 links something you can't get away
:with with a derailleur system. People who are only using Dutch utility
:bikes with a gearhub never have to replace the chain if they buy a new
:bike, let say, every 3-5 years and are very surprized when I tell them
:this is standard maintenance on a roadbike and even more on a ATB. They
:think their chain doesn't wear because of the enclosed chainguard but in
:reality the chain does wear but they can get away with it.
:

I have somthing like 3K miles on my 8sp shimano. I've gone through a
couple chains, from rusting (they pave the roads with salt in
chicago), not wear. There was no visible wear on the cog or
chainring when I last changed chain. I supsect rolholf uses chesse to
make their cogs.

--
sig 59

That proves again that you have to replace the chain before a certain wear to save the cog if that is what you want. A 'couple' of chains in 3K miles is quite a lot though. My statement was that a singlespeed or hub geared bike is not easier on a chain. The Rohloff cog is a beefy steel cog. I don't know if it has some kind of surface treatment.

Lou