How to 'mushroom' pin on Shimano CN HG 53 chain.
 

I'm new to 9 speed chains but can well understand that the 'mushroom', or 'peen', on the end of the pin would be a strengthener.

What I do not understand is how one would effect this. Is it done with the chain breaker tool, or what?

TIA

Once you break a Shimano chain, do not reuse the old pin - you need to use a new pin (available at your LBS). The new pin is inserted with a chain tool and not peened like the factory pins.

I agree that peening adds a mechanical lock (and friction) to the pin, where the replacement pin is held by friction. But obviously, Shimano replacement pin design is fine and works.

(I hate dealing with those replacement pins - one reason why I use SRAM and KMC chains with reusable master links).

Yeah, just get a master link (Wipperman or KMC) and be done with it. Being able to pop the chain off makes cleaning *the bike* a lot easier.

While you're at it, buy a spare and keep it in the bike bag just in case you break your chain out on a ride. That's not likely, but it's also only a tiny little item so it's no trouble to carry a spare.

Rohloff did make a chain tool that flaired the end of the chain pins and current Campy 11-speed chains use the same technique (but require a different far more expensive chain tool) to join them but Shimano's replacement joining pins don't require that and are reliable anyway.

A good idea. I keep used masterlinks in my seat bags as spares. I've never had to use them, but did give them to others who snapped chains on a few occasions - and each time, it was a Shimano chain.

+1 on this (makes for easy
removal for cleaning as well...
bud

Actually, the replacement pin is peened, but since driving out the original pin enlarges the hole in the link, the replacement pin is slightly larger in diameter. You can feel it snap into place when installing it.

I agree with the others- the SRAM master links are much, much nicer than the Shimano replacement pin. In fact, I've converted to using SRAM chains exclusively on my bikes.

+1 for the past 12 years. I recently switched to KMC for 10-spd, since SRAM 10-spd masterlinks are not supposed to be reused.

The KMC master links I have, from a couple of years ago also say
"Do not reuse". Not entirely clear what that means, but I
interpolate do not use old master link with new chain.

There's nothing you can do to make your chain stronger. On the other hand, there's plenty you can do to make it weaker.

+1, the Rohloff Chain tool's advantage is it peens the end of the pin.
but, typically you only remove the pin to get the chain length
then join the ends with a quick link of some sort.
Now new chains usually come with one..
chain tool, common sort, and a spare quick link will get you home .
or back on the road when Mid Tour.

I reuse SRAM power links for the life of the chain it came with. I don't reuse them on new chains.

SRAM PowerLinks and SRAM PowerLocks are different. PowerLink is what their 8 and 9-speed master links are called and are considered reusable, at least for the life of the chain they came with. PowerLock is the 10-speed master link and SRAM claims they are not reusable once removed.

Note to Mudpie: The only chain I've ever had to repair on the road was a Campy. Not mine but another rider's. I personally have never had a Shimano or Wippermann chain fail and I typically use them for 6000 - 8000 miles before replacement.

My encounters with broken chains were on mountain bikes. In one case, the rider claimed the chain was a month old. I wish I had inspected the busted link to see if it was related to the replacement pin perhaps incorrectly installed. I personally never had any chain fail (SRAM or KMC or Shimano), but I attribute it to good maintenance and regular inspections.