Removed link pair. What next?
 

First, sorry if this has been discussed before. Time is pressing and I can't search for a similar topic.

My Shimano 105 chain broke when I was riding in the mountains and I fixed it on the side of the road by removing a link pair. Is it okay if I keep the chain shorter than before or should I add a link pair to replace the removed one?

When the chain is on the big ring + big sprocket, the S-turns at the derailler are very pronounced, which makes me think that the shortened chain is ok.

I'll visit the LBS tomorrow to true the wheels and ask them about the chain as well, but I'd like another opinion, as well, so that I won't spend the money for nothing.

Btw, this is the original chain that came with my bike and it is not stretched at all.

If the bike will shift into big-big with out breaking anything, the chain is long enough. The rear derailleur can be in an absolute straight line but that's ok.

However, how did you repair the chain at the roadside? Did you partially or completely push out a standard pin and rejoin it using the same pin? If so you have a serious weak spot at that point in the chain and it is more than likely to fail there. If you used a master link or Shimano's specific joining pin, you are ok.

In this picture of a 105 - 5700 chain:
http://www.competitivecyclist.com/im.../98508_i_1.jpg
you can see that each pin has a little "hole" in it's center.

One or two pins in the whole chain don't have that hole; they are flat.
A couple of rides before, I removed one of that flat pins so that I could properly clean the (very dirty) chain, and then reinstalled it. The chain failed at that flat pin.
It it matters, I accidentally removed that pin completely and it was hell to put it back... it was understandably weak.

When I fixed it on the roadside, I used the standard, partially removed pin from the joining link.


Another failure is waiting aroung the corner, I reckon...

Yep. Apparently you removed the original joining pin when you took the chain off for cleaning. These are NEVER to be removed. If you do remove the chain, break it by removing one of the "standard" pins and replacing it with another specific joining pin or a master link. At this point, your chain is a failure waiting to happen unless you can find and remove the pin you just pushed out and replace it with a master link.

BTW, master links are definitely the way to go if you want to remove the chain for cleaning. KMC and Wippermann Connex links are compatible with Shimano chains and SRAM, KMC and Wippermann chains come with master links.

You should probably get a new chain and some pins or master links and read up on how to care for your new chain. I like the links and normally carry an extra. I've never needed it myself, but friends have.