Originally Posted by
Slaninar
Good point. Makes sense. Have you had problems with such set ups - with inner cage hitting the middle chainring when shifting to the big ring? The "height" difference between 38 and 42 is a little over 1 cm.
Actually the radial difference between 38T and 42T chainrings is about 8 mm. Most current front derailleurs have a manufacturer recommended minimum tooth difference between chainrings and it's typically 10 teeth or more.
I haven't tried tried closely spaced chainrings in many years since the mid-80's 46/42/26 triple crank and Sun Tour ARX front derailleur system I mentioned above.