Campag chainset with shimano levers

[bajs-eye]

I'm sure this has been asked before but could I use a campag chainset with my shimano 105 STI levers? I know that this would be bad news with the cogs on the back but is it the same story with the front rings?

 

[Eastway82]

I'm sure this has been asked before but could I use a campag chainset with my shimano 105 STI levers? I know that this would be bad news with the cogs on the back but is it the same story with the front rings?

Should be no problem at all.

 

[alfeng]

I'm sure this has been asked before but could I use a campag chainset with my shimano 105 STI levers? I know that this would be bad news with the cogs on the back but is it the same story with the front rings?

It should be "okay" ...

Supposedly, Shimano's pins & ramps are slightly superior ... but, everyone seems to have been allowed to COPY them, for the most part.

FWIW. I can tell you that the 9-speed 105 STI levers will even shift between non-ramped (e.g., 8-speed) chainrings ... I just (as in the last few days), put an old set of 9-speed 105 levers on a bike with an XT (!) front derailleur & a 52/39 double chainset/(crankset) -- this has to be considered a worst-case-scenario when mating components.

A little fiddling (as with any "new" front derailleur to get the stops), and voila -- the shifting seems fine with the bike mounted in a stationary trainer ... well, good enough (for me).

Now, I am able to make the chain baulk when moving onto the larger chainring when I am when making an indecisive shift OR when not making a complete shifting motion which leaves the chain in limbo ... and, I can see where having pins & ramps that lead chain onto profiled teeth could expedite the shifting ... but, if I do MY part, then the shifter & chain seem to do what they are supposed to.

Of course, as they say, your results and/or demands may vary ...

 

[bajs-eye]

I was concerned with the indexing, but it seems like that won't be an issue - so thanks for the replies.

 

[rek]

Now, I am able to make the chain baulk when moving onto the larger chainring when I am when making an indecisive shift OR when not making a complete shifting motion which leaves the chain in limbo ... and, I can see where having pins & ramps that lead chain onto profiled teeth could expedite the shifting ... but, if I do MY part, then the shifter & chain seem to do what they are supposed to.

I'd reckon that the occasional baulky shift could have more to do with the choice of front derailleur than the crankset or chainring ramps. (Not saying that ramps wouldn't help make an extreme-case situation shift a bit nicer, though..)

The path and angle of movement that a mountain bike front derailleur cage makes is slightly different, and less than optimal for, shifting a road crankset. (It's been optimised for a mountain bike crankset, which has smaller and more closely-geared chainrings.) Think in terms of how much vertical movement the chain needs to get from one ring to another; because of these ring differences, MTB drivetrains don't have to 'push the chain up' as much as a typical road drivetrain.

Front derailleurs have a set of specs defining what size big chainring and what sort of chainring tooth differences they're designed to shift with. The fact that your extreme case works adequately goes to show how much lee-way there is with this sort of mixing and matching. You can usually get away with exceeding it here and there.


e.g. the 'official' specs are:

XT front derailleur; maximum big ring 44T, capacity of 12T between middle and top rings, and 22T between all three rings (bottom to top).

Ultegra front derailleur; maximum big ring 50-56T, capacity of 15T (for a double crankset)

('capacity' is the difference in teeth between one ring and another that the derailleur is capable of shifting from/to)


hmm.. I've forgotten that this has absolutely nothing to do with the original question, but I can't bear to delete the post just for that