when you own 10 personal bikes and manage about 30 more for other people, chain management can get a) out of control and b) expensive .

Overhauling other people's bikes I have learned some hard lessons from a few catastrophic chain failures, usually 9speeds, where I broke the chains for cleaning and stupidly assumed I could just repin the chain to reinstall it and reuse it. Wrong! (as one would expect 2 of 4 times when the pin wiggled loose, the chain just rolled harmlessly over cranks and off. the other two times though the link with the loose pin, releasing on the underside of the rotation pulled through the derailleur with catastrophic results - tacoed derailleurs.)

Since those experiences I have been very very cautious, maybe overly so. But now that I am facing $50-100 replacement chains (x20 you can see why that is getting expensive.) I would just like to understand the rules of chain repinning.

Yesterday I measured my own 8speed setup and it was over worn. time for replacement.

picking through my stash of spare chains, I came upon an almost new SRAM PC-48 (which apparently is good for 6,7 and 8speed systems.)
However, I saw too that I somehow had overlooked the Magic Link on it and had broken the chain with a break tool (the magic link was still installed, the pushed pin was just a few links down. It must have been late...)

So, question is. Can I simply reset that pin and reinstall the chain using the Magic Link and go on my merry way? (this is an 8s Dura Ace derailleur so I would like to not put it at risk.)

otherwise, are there any general and global "rules" for when one can and canNOT pin-reinstall a chain (that is to say without using a Magic Link or the special Shimano pin)? (I think I can safely assume that 9S chains and up should NEVER be repinned.)

Thanks

Peter

I don't know. I just use the "quick links" for my chains and don't have to mess around with pins any more.

No, you cannot use the pin again but you can use more than one SRAM link. However, the 8 speed chains are so cheap that I would just get another and use the link you have for a spare.

Hole stretches in outer chain plate to let rivet expanded end pass thru,
Buy, on my own bikes I managed to pin the chain back together,
before Quick links, existed... using the chain tool,
and then, adjusting for the tight link that usually results.

but then again, old tourist pace.. I was not one to force shifts
in the middle of steep hills , by anticipating gear changes..
people seem to want instant shifts, and the chains come apart.

Sedisport chains.. was consumed in the Sram Acquisition of Sachs group.

Definitely use the PowerLink; since you are managing many bikes why don't you see if you can get a quantity discount on them? You might consider picking up the Park Tool Master Link Pliers while you are at it, it is very convenient for opening the links: Park tool quick link tool

I re-use Shimano 8 speed pins all the time. In fact, I never buy new pins when I clean those 6-7-8 speed chains. On rare occaisions, I've done the same with 8 speed SRAM chains. I've never had a chain separate due to the pin coming loose. But this only applies to 6-7-8 speed chains. For some reason, 9 and 10 speed chains are not as tolerant.
I've heard of too many horror stories when others did re-used a pin on 9 or 10 speed chains, therefore, I always replace the pin on a Shimano or Campy chain and never pull a pin on a SRAM chain. Don't know what the difference is, but there definetely is one.

When you drive the pin back in use a punch to rivit it into place.