bradtx

Hi All, I had a tick whenever the chain was running at an angle, the greater the angle, the louder the tick. Back home I discovered the Shimano replacement pin was loose. I removed that full link and started to install a new replacement pin and found it would almost install without the chain tool.

Turns out that 7S and 8S Shimano HG chains use a different diameter pin. The diameter for the replacement pin is 3.56 mm and the diameter of the factory installed pin is 3.66 mm (Allow some inaccuracy for my gauge, please. . I had installed the previous replacement pin, I just didn't notice it was easier to install than usual.

Maybe this will help someone in the future.

Brad

PS Chain wasn't the problem, see below.

Wilfred Laurier

afaik
there is no distinction between 7 and 8 speed chains
and there is only one type of pin for this width of chain

in fact
if you look at tech documents from shimano
they make no distinction between 6 7 and 8 speed hg chains

https://bike.shimano.com/media/techdo...9830686193.pdf

maybe you have a ug chain

bradtx

Nope, links are stamped HG. I thought the chains were the same also which is why I used an 8S pin.

Brad

bradtx

Hi All, I have to correct what I found as the problem. It seems the two 8S replacement pins I used were defective. They were defective because the working part of the pin didn't increase in diameter from the section that installs as a guide and then is broken off. I'd never measured the pins before so I just didn't know better.

These two pins were bought as spares from my LBS several years ago, I found another 8S pin loose in my parts box that did change diameter between the two halves of the pin and it is not loose after installation. It installed with very little resistance also so initially I wasn't sure.

Brad

jralbert

Somewhat off-topic, so don't let me distract from what looks to be a useful thread, but it brought to mind the time I had just after I bought my first "nice" road bike; I was so worried that buying used I would miss some fatal flaw and end up throwing away thousands on a useless junker, so I inspected that bike within an inch of its life. Satisfied as possible, I forked over the cash - but on the first ride I encountered an unmistakable 'tick-tick-tick' in time with the crank rotation rate. I was mortified - the crank arms were cracked, or the bottom bracket was ratched, or maybe the frame was structurally unstable, or oh god what have I done?! Fifteen feverish minutes later I realized it was the end cap of the FD cable tapping the drive-side crank arm as it went by. Phew!