Originally Posted by
Herzlos
So would my only potential problem be the chain rubbing on the inside of the ring on changes? Is that likely to cause something to catch and cause an accident or just be a bit of extra wear/friction when trying to change?
In the same vane, if I fit it and I can change back and forth without anything colliding when on a repair stand, then I'm good to go?
Most modern big rings have chain pickups on their inner face, so you would definitely want those to clear the chain when on the inner ring.
AS I said, my Ultegra 52/34 has no issues like that and shimano rings are noted for all the pickup features they have to assist the UP chain shift...
All this assuming (as with all multi-chainring setups) that you're not using the small/small crosschain...
... an interesting tech tidbit - what is the actual distance/spacing between rings ??? I think when I have a moment later, I'll see if I can mic that distance on my Ultegra and 105 Mid-Compacts including the the new 'deep' Mid-Compact 52/34...
my thoughts on chain - If you're not cross-chaining 'Big to Big', then given just a 2 tooth jump on the 2nd to largest cog, would at the most be a one full chainlink diff.
And depending how the current chain was cut, most RDs have no problem handling that... especially the newer clutch RDs designed to work with wide range cassettes (or your std long cage RD...)
Most you, might have to add is one full link - wide/narrow.
if there's 2K miles on the current chain - prolly a good time to do a 'chain check' for wear/'stretch anyway...
UPDATE: so I tried to mic the spread/distance between the rings on my R8000 Ultegra crank, and there was just no way to get the mic in there to measure properly... But, if a crank is design for 'compact' type 16 tooth spread, then the distance between rings should be same for most all cranks... course, it always, depends... LOL ... still thinking that 2 tooth small ring difference - 18 tooth spread - would be workable...