Quote Originally Posted by KnottedYet
I've been under the impression that *shifting* issues are caused by the front derailleur and *gearing* issues are the crankset.

...(and I'm still confused about levers vs FD. Cuz going to the big ring is a function of the lever, while going to the smaller rings is a function of the spring in the FD. 105's have better springs so they drop down gears better, but how does that help the upshift? Does the 105 have a better backplate? And if he just fiddles with the H-limit screw on the FD the bike has now, couldn't he adjust the range of the current FD so it's easier to get the chain onto the big ring? That's FREE and saves you even more money for upgrades later!)
Hi Knotted,

As usual, it's more than one thing.

You're right that *gearing* isses can be addressed by changing chain ring sizes (the crank set), but the cranks also affect shifting: the mechanical features designed into the chain rings also help the front derailleur move the chain among 'rings.

The Lemond Etape is listed with Bontrager cranks; they work great on our tandem, but in my experience Shimano chain rings really do make a noticeable difference in front shifting performance.

Going to bigger rings is a function of the system, including the lever of course, the shape of the derailleur's plate (you mention both), but also the shape and lateral stiffness of the chain, the presence (or lack thereof) and design of the pins 'n' ramps on the chain rings, cable and housing stiffness and friction, frame angles, chain line, etc. etc. And adjustment of course!

Going to smaller rings is a function of the derailleur spring, plus presence and design of release teeth on the crank, matched set of chain rings (so the chain engages the smaller ring instead of riding on top), and most of the design features listed above, including good adjustment of course.

So a good mechanic *may* be able to fiddle with the H-limit screw, but that's only a small element of good front shifting.

HTH!