To cut a long story short , replaced my Sram Rival 50 and 34 tooth chainrings with FSA ones as they were cheaper. Now I think im right in saying that there is no difference between 10 and 11 speed in chainrings. After the bike was serviced the mechanic stated the gap between the rings was too big and that on a bike stand the chain had dropped a few times but under load and being careful it would shift. He recommended buying the proper chainrings.
Was out for a quick blast and hitting a hill dropped from 50 to 34 tooth only to snag the chain and ping 1 half of the quick link into a ploughed feild So after a long walk home can anyone advise what I can replace the Sram Rival chainrings with to get the proper gap and avoid another catastrophe. Also can I buy 10 speed rings and use with an 11 speed casstte. Luckily i was close to home but could have been miles away and came a cropper.

thanks folks.

Is he talking about the 16T gap between the rings themselves? I know a lot of roadies who don’t like compacts for that very reason, just too big a drop. I’d have thought a 10 speed ring would be fine with an 11 speed chain, but no experience of it directly.

Yup , never had a problem with the old sram rings but when he fitted the new FSA ones he reckons the gap in between the rings in bigger. I would have thought the chainrings themselves were the same width and both compact 50 and 34 tooth.

Are we talking about the difference between chainring sizes, or the distance between the chainline on each of the two rings?

And where did the chain snag in order to cause the link to ping off? Between the two rings or behind the inner? Is this the behaviour the mechanic was referring to by “dropping the chain”?

This can happen on Shimano 10/11 speed chainsets as the rings are a little dished/offset*, It’s especially bad when mixing Shimano/non-Shimano rings, but if you replaced both rings at the same time the spacing (as in between rings horizontal distance) should be the same, althogh there is some minor variation in spider/tab thickness between manufacturers but not much.

Whatever solution you go with, remember to stick a spare quicklink in with your tube+pump from now on 😉

* might be the same with SRAM as well but I’m not that familair with SRAM road gear.

Thinking more about this , im pretty sure the chainrings must be the same width. The difference is surely the shifting teeth are different . The tabs on the fsa rings can not be mounted behind the crankarm like they are in the proper chainrings. Sram also have that horrible chainring hidden behind the crank arm not sure if that would affect the gap in between though.