Indexed chain ok to break?
 

Hi all!
New to indexed drivelines. Ridden vintage Campy forever. Just picked up this’06 Lemond. Shimano 105 equipped. The chain is caked with gunk. It shifts great. Go figure. Can I just break the chain, soak and scrub it? Just replace it? It shifts so well, and I don’t want to mess that up!
https://cimg4.ibsrv.net/gimg/bikefor...6528bb2bb.jpeg

You can break the chain to clean it but you will need a quick link to reconnect. Or the appropriate pin if Shimano. The links are speed specific. KMC and SRAM are common choices.

ok, thanks! It’s 9 speed. I see that makes a difference.....

Yes, you can break the chain to clean it, but first look closely at the chain to see if there is a quick-link already installed. If you find one, use that to open the chain. If not, break the chain anywhere and use an appropriately-sized quick link to re-join it after cleaning.

As mentioned, yes for quick links. Easy to use and have been proven reliable for about a bazillion chains in use. Measure your chain to determine if it needs replacing rather than guessing.

Check the chain for wear before you spend your time making it all clean and pretty. You can just measure with a steel tape or scale (ruler) from one pin and see what pin falls near the 12" mark. If that pin is more than 12-1/16" then it's time to think about getting another chain. If it's 12-1/8th then it's beyond time and your cogs might also be worn and need to be changed.

The new chain will be all clean and lubed. Just break it at the proper length and hopefully you bought one with a quick link. Though pins are okay too, just a little more trouble if you ever have to take that chain off before time for replacement.

Oh... we don't refer to the chain as indexed. We will refer to your shifters as indexed if they aren't the old style friction shifters.

When I got into Campy 10s they had a nice long procedure about how not to break the chain, or use a specific replacement pin and tool, etc. etc.
Yeah, never followed any of that. Now I do use a quick link on all my chains but a few of them do have non compliant pins in them ala 1980's chain maintenance.

Some chains are sided but not directional.
The side of the chain with the writing on goes outboard away from the frame.

Barry
.
OH BTW - the quick link comments come from shimano's use of one time use pins.
Once you push a pin out, you can't just old skool and push it back in.
Shimano will sell you a new pin about 1/8" longer than the old pin. You push it in a break off the excess length.
Even shimano has recently come around to the use of quick links, and now provides them with new chains.
Although IIRC, they still consider them one time use. Rightttttt !