I know that this has been covered several times before with the usual advice being to arrange the smaller of the two rings in the granny ring position and the large ring in the middle ring position of the 3×9 chainset; this would also leave the option to fit a bash guard if required.

Presumably the ideal ring position to give the best chainline across all of the cassette would be a 2×10 specific setup which would position the rings either side of the middle ring position of a 3×9. However, since I have a 3 ring chainset a 10 speed cassette is the same width as a 9, is there any reason not to set up the two rings in the middle and outer ring position on the 3×9 (from a chainline perspective I assume that this would very slightly favour the higher gears than the lower as with the other way around)?

I ask as I don’t want to fit a bash guard (and this might look a little tidier) and because a little extra clearance between the chainstay and chainring teeth doesn’t seem a bad idea from a chainsuck point of view.

Make sure it’s not a Mk1 Soul, apparently can’t be done. Unless Cy just wants me to buy another one! 👿

Anyone?

Is this a really stupid question then?

not sure if this is the best way of doing it, but I am using the smaller two ring positions and moved an extra bb spacer to the drive side to make the chainline a bit better – seems to work with no bad chainsuck or rubbing apart from in extreme small small situations

I wouldn’t do it

You won’t be able to use such a small inner ring (30T rather than 22T if you have a conventional 4 arm 104/64 BCD chainset) and the bike won’t be very happy in big/big.

Ah, right, thank you; I hadn’t thought of that!