top swing and bottom swing!?

[dekerf2]

I understand the "top pull - bottom pull" concepts, but could do with some light casting over the reasons, if any, why one should use either bottom swing or top swing front mechs.
Oh and if it helps my frame is a 1994 kona hardtail.

I suppose what im asking in short is does it matter which type i use and if so why does it matter?

cheers in advance

 

[FluffyChicken]

Old bikes (quality one) tend to have oval tubes near the bottom bracket, you cannot fit top-swing (low band) to these, hence you use 'conventional' down-swing (high band) models.

Eyelets for bottle cages on modern bike probably tell you if you cannot use a conventional down-swing on them.

All I can think of is the top-swing may bit stiffer due to the placement nearer the top of hte chainrings. That and I think rear suspension bikes drove the demand for the change (before the e-type came out)

 

[Kona Paul]

You need a bottom/down swing or conventional.

You can also read about swing and pull types here:

http://en.wikipedia.org/wiki/Derailleur_gears

 

[Xesh]

All I can think of is the top-swing may bit stiffer due to the placement nearer the top of hte chainrings.

I don't think that there's much difference, operationally, between the two. Originally, when Shimano released the top swing design, it was claimed that the front mech was less vulnerable to damage because it was lower down than usual. Obviously a load of crap. When was the last time you trashed a front mech by hitting it on something?

One thing I have noticed, however, is that the pivots on the top swing mechs wear out a lot faster than the conventional ones. Also some of the conventional types have adjustable spring tension (like the XT ones). I always go for the conventional ones if I have a choice though.

 

[andrewl]

Obviously a load of crap. When was the last time you trashed a front mech by hitting it on something?

I've actually trashed two bottom swing front derailleurs with sticks coming up from the front wheel and spearing the parallel links and cage on the derailleur, so yes it does happen.

 

[Xesh]

I've actually trashed two bottom swing front derailleurs with sticks coming up from the front wheel and spearing the parallel links and cage on the derailleur, so yes it does happen.

You must have been unlucky then. I doubt that whether the front mech was top or bottom swing would make a difference in that case.