Top tube shifter mount

So why isn’t this a thing? Seem kinda alright. Can’t really think why it’s not a good idea. Admittedly I haven’t thought very hard about it.

Snot such a bad idea, but it’d need seat tube and seat stay guides down to the RD. Stem mounting put the shifter in a similar spot and makes use of the usual downtube/chainstay cable runs.

Farkin cables! How would they work!?
Maybe across the top tube then down the seat stay?

Cables - just wrap them a couple of times around the top tube and stay.

And maybe snug them down with a couple of zip ties here and there to stop them rattling.

Hufnagel do a stem mounted shifter, and I’m sure I’ve seen a toptube mounted one on one of his bikes.

There’s the possibility of hitting your knees on them when out of saddle.

It’s a bit of a thing maybe

DSCF0984 AB DIL02 by kick-my-pan, on Flickr

(Very cool photostream by the way)

It’s been done plenty by old and new.

There’s pro’s/con’s … Disc-Ville | Flickr

Because of brifters?
Also what about hitting your knees?

Have you ever had your knee hit the top of the headset or stem when out of the saddle and leaning forward?

have you ever met H? anything is possible!

Huh? Didnt you just agree with me a few posts back?. Top tube shifter would def put your knees in the firing line

couldnt you just run them forwards again, pass down the headtube back to the original bosses. could easily add it to a frame with a clamp on shifter mount thing couldnt you? or weld/rivet in one of those tabs you can buy on ebay. not super neat but probably neater than going along the TT/seat stays. like this:

Edit: actually, I’m thinking of those frames that just have cable guides on the DT rather than shifter bosses. still, can get the guides that go over shifter bosses.

Sorry, I thought you were questioning my comment about it, not repeating it.
All good