Why do Shimano chain connecting pins exist?

[Titanium]

Has this already been trawled over before? I imagine it's been discussed many a time.

Anyway, so why did Shimano introduce Chain Connecting Pins? Chains seemed to be getting on just fine without them. You could use a chain rivet tool to 'break' the chain anywhere, and then re-join it all up again afterwards.

Some Shimano chains use, or need, a new connecting pin everytime you break the chain apart. Why? Was there any point, or any advantage over existing Sedis / SRAM / etc chains? Seems to me like a solution in search of a problem.

Any knowledge or comments much appreciated. I'm not needing advice actually, as I mostly use SRAM chains - it's just me being curious about this subject. Reminds me of built-in obsolescence.

Cheers.

 

[andrew_s]

Up to 8-speed, the pins were a bit longer than required so that the pin protruded maybe 0.2mm past the outer link plate on each side. With 9 & 10-speed cassettes, there isn't as much room between the more closely spaced sprockets, so they had to make the chain narrower. The inside width is fixed at 3/16 so they had to make it narrower on the outside, partly by making the pins shorter so they didn't protrude on the outside of the link plates. The lack of protrusion meant the pins had to be peened - ie bashed on the ends to make the end of the pin bulge a little and grip the inside of the hole in the plate more tightly. That means that when you try to use a chain tool to drive the pin back in, you are trying to force a fat pin into a small hole that's already been enlarged slightly over its original size.
The end result is that you generally don't end up with a reliable join.

Shimano came up with a replacement pin that had a snap off tapered end to get the pin started in the hole, and was slightly oversized at the ends to grip in the already enlarged link plate hole.
Sedis/SRAM/Wipperman/Taya/KMC all use various designs of two part outer links that separate without driving the pins out.
Most people prefer the two part links. They are reusable if you split the chain for cleaning. For on the road repairs, a spare joining link isn't any more difficult to carry than a spare pin, and you don't need a pair of pliers to snap the end off.

Another option might have been to make 4mm chains instead of 3/16. These would have been incompatible with all existing kit.

 

[Titanium]

Thanks Andrew. Very good of you to write such a comprehensive explanation.
It's good to know about that sort of thing, and you've helped me understand.
Cheerio. Mark.

 

[Steve Austin]

sedis sram sachs are the same company

I like the Shimano pin. if you join a chain properly and don't feck about with it, a Shimano chain will work fine for the life of the chain.
ok, you can't split the chain easily and everytime you do, you need a new pin, but then why does anyone need to split a chain?

There is nothing to stop you using a splitting link on a Shimano chain. I use KMC links as they are easier to split that Sram. and Sram do have an air of the emperors new clothes about them..

Viva le Shimano

 

[april74]

Stick to 7 or 8 speed. That's what I do. All the drivetrain components can be bought cheaply.

I can still thrash most of the weekend 9/10 speed carbon fibre frame boys into the dust.

It's not about the bike.

 

[venn]

Hi guys,

I bought an 8 speed Shimano chain IG70 and it came with a pin attached to the outer plate of the end link. This pin was with a regular length, not longer like the snap off pin which came in extra small bag.

I cut the chain to the desired length from the opposite side to the one with already attached pin and used that same pin to install (join) the chain.
I assumed that the extra snap off pin is to be used later if/when I need to break the chain, while the short pin that was already factory installed didn't need to be long as the lead edge was already inside the first outside plate and there's no need that pin to be guided by a snap off piece.

Later on I visited Park Tool website and it looks like I should have used the snap off pin to drive out the short pin attached to the outer plate and finally snap the end of that pin.

Did I really make a mistake using the short pin? If so, what was the point of having that pin at all?
If I did it wrong, what should I do now - drive that short pin out with a chain breaker tool? And of so, which direction should I pick - keep the same direction as I've inserted that short pin or back it up i.e. the opposite direction it went in?

Thanks for the advice

 

[e-rider]

Hi guys,

I bought an 8 speed Shimano chain IG70 and it came with a pin attached to the outer plate of the end link. This pin was with a regular length, not longer like the snap off pin which came in extra small bag.

I cut the chain to the desired length from the opposite side to the one with already attached pin and used that same pin to install (join) the chain.
I assumed that the extra snap off pin is to be used later if/when I need to break the chain, while the short pin that was already factory installed didn't need to be long as the lead edge was already inside the first outside plate and there's no need that pin to be guided by a snap off piece.

Later on I visited Park Tool website and it looks like I should have used the snap off pin to drive out the short pin attached to the outer plate and finally snap the end of that pin.

Did I really make a mistake using the short pin? If so, what was the point of having that pin at all?
If I did it wrong, what should I do now - drive that short pin out with a chain breaker tool? And of so, which direction should I pick - keep the same direction as I've inserted that short pin or back it up i.e. the opposite direction it went in?

Thanks for the advice

I think you got it correct first time. Use the factory installed pin first time and then the spare pin in the future should you ever need to join the chain again. Lots of on-line sellers don't even give you that spare pin - you just get the one that is already half-in the end link.

 

[mickle]

Shi**no, in their arrogance, refuse as far as is humanly possible to use any design, component, material or system which did not originate on their premises.

Shi**no threadless headset anyone? That's right, there isn't one. Before the introduction of threadless they used to make some great threaded headsets did Shi**no but they refuse to pay the licence to Ahead. This is the real reason they use those stupid expensive pins.

Don't get me started on stack height, or Biopace, Microdrive, or the GripShift spring tension case, or rapid rise.

Bunch of arse.

 

[PpPete]

Don't get me started on stack height, or Biopace, Microdrive, or the GripShift spring tension case, or rapid rise.

Go on - we know you're dying to.

 

[Fiona N]

Shi**no, in their arrogance, refuse as far as is humanly possible to use any design, component, material or system which did not originate on their premises.

Shi**no threadless headset anyone? That's right, there isn't one. Before the introduction of threadless they used to make some great threaded headsets did Shi**no but they refuse to pay the licence to Ahead. This is the real reason they use those stupid expensive pins.

Don't get me started on stack height, or Biopace, Microdrive, or the GripShift spring tension case, or rapid rise.

Bunch of arse.

Lovely to see some passion which isn't directed at another poster

 

[psmiffy]

Pre Shimano pins when replacing a chain it could be a right pain to split the chain and then rejoin it - so when pins happened I was right pleased - following the introduction of quick links I now us either or - the links are not necessarily that easy to use but if I am just cleaning components then it is the most convienient way to go

 

[youngoldbloke]

The Shimano snap-off pin appears to be relatively sane and sensible when compared to the Campagnolo 10 speed link system - what's that all about and why? I use a KMC link myself. Works perfectly.

 

[mickle]

Lovely to see some passion which isn't directed at another poster

I suspect that Mr Shi**no doesn't care what I think.

 

[mickle]

But Micro Drive though. A brilliant idea launched by Suntour. Reduced chain ring sizes and sprocket sizes resulted in significant rotating weight reduction, improved shifting speed, increased ground clearance and less chainring flex. Running a reduced BCD the new system was a great success in their top groups; XC Pro, XC Comp, Xc Ltd etc. Shortly thereafter Shi**no, having initially dismissed the concept, launched Compact Drive.

Shi**no used the same outer ring BCD as Suntour's MicroDrive but changed the granny ring BCD by 2mm. This ensured that CompactDrive wasn't compatible with MicroDrive. Nice. And then they tried to convince everyone that it was their idea!

Makes my blood boil so it does.

Don't get me started on stack height though, you'll be here all day you really will.

 

[lukesdad]

What about the Dura ace triple BCD, that was a classic.