guy153

My left-hand bar-con (I think it's a DuraAce) that shifts the big ring (it's a triple) is kind of low on friction. Even if I tighten the screw up rather tighter than feels right it tends to slip down a little when on the big ring. There is actually a click-point for the big ring but this isn't really a solution as it usually needs a bit of trimming anyway. Does anyone know how they work or have any tips for enhancing the frictiosity? I assume there's some kind of washer in there that is deliberately sandpapery or something? Can this be replaced or re-vulcanized or something?

himespau 

Stupid question, but is this one of the ones with the D-ring on the bolt that allows you to switch it from indexed to friction?

rccardr 

Which version? Sure it’s a DA? Pics would help.
Older ones might be fixable but if it’s one of the later versions with sealed internals, likely toast.

BTW, all left side DA barcons are friction, there is no indexing option.

Bonus points for an excellent thread title!

guy153

The RH one has that feature but not sure the LH (which is where the problem is) does.

himespau 

Oh duh, of course, you said left and I missed it. Those are friction-only. Was hoping somehow things had been mis-aligned halfway between friction and indexed and there would be a simple fix. Don't mind me, I'm just a bit slow sometimes (most of the time).

guy153

Here are some pictures, first the basic shifter:



And this is how it comes apart:



It looks like the "friction" is achieved right on the outside. There are some little raised lumpy bits right on the end which sort of ratchet against those ribs on the inside surface of the screw that holds it all together:



A better picture of the screw, showing the ribs. These are the two surfaces that are supposed to rub together (and it does have a nice sort of clickety ratchety action):



But it looks like the lumpy bits on the inside of the shifter are basically kind of worn from use. So I don't know what can be done here. It might just work if I have the whole cable a bit slacker so that the lever is closer to being horizontal when in the big ring. That way there will be much less leverage trying to pull it back down.

Camilo

You could experiment with washers - rubber or fiber? My first inclination would be to find a dense (as opposed to soft/fluffy) fiber washer and see if it works, thinking rubber might be too grippy. But while I was at the hardware store, I'd buy both for a nickel each, maybe various thicknesses if they have them.
If it's just plain friction, at the right amount, that you're looking for, that would be a low tech solution.

If not, check eBay. If you can't find a left/friction shifter that you like, buy a set at whatever price point that suits you and sell your right/indexed one - there will definitely be a market for that.

rccardr 

Hunh.
You might want to try cutting a series of five or six narrow slots in both the bottom of the mounting bolt and the face of the shifter to increase the friction there.
But, honestly, suspect these are simply worn out and should be replaced. Plenty of good used ones out there.

dedhed

https://www.mgcycle.com/index.php?ma...roducts_id=402

guy153

An update to this. I've installed the shifter but with the cable a little bit slacker so that the big ring corresponds to it sticking basically straight out. In that position the cable has much less torque to pull it back. This works absolutely fine (and I think I suggested it earlier in this thread). So no need for a new shifter.

Riding with these shifters again I'd forgotten how nice the right-hand one feels. Old-school (so DT or barcon) but indexed probably the best feeling gear shifts of all time.