Chain change

When I was doing my spring cleaning and tuning on the bike, I changed the rear cogset. I'd forgotten the new chain so I had to ride a few kilometers with the old chain to buy a new one. It was horrible. There was these crunching sounds coming from the new rear sprockets. The old chain and the new sprockets= bad.

I've heard that when you can see the air between the cogs on the big wheels, it's time to change the chain. As you can see, my chain was due to be changed soon, anyway.

I hanged both chains from a hook to compare the lengths. Looking at the very first links, the old chain does not look too bad.

I was supposed to rotate the picture but forgot. But you can see the chain links even without tilting your head 90 degrees to the left.

But at the other end, about 70-80 chainlinks later, one can quickly see the difference. By calculating the pixels from the first picture I got about 0.5% change in length, and here its almost half a link. Maybe 75% of half a link, which also gives us the 0.5% "strech" in the chain.

 

The new chain fits snugly. The bright spot you can see under  the second link from the left is just reflection from the sprocket. I know, because I had to check it if the front sprocket is worn out. The front sprockets are fine for a while. Also there's no extra sounds from the rear sprockets, so ride is quieter with the new chain.