vtchuck

So as part of "codgerizing" my last road bike to make it rideable in my twilight years (lower gearing, platform pedals, wider tires) I have removed my downtube shifters.

Purchased Velo Orange thumb shifter mounts and DiaCompe levers. Assembled and I'm confused as to how to position them on my bars. As you can see in the photos, I will have to mount them
more outboard on the bars.... but on top...below,,,, forward?? The only thing I am somewhat sure of, is that the cable housing extensions should face towards the center.

Thanks in advance.

pfaustus

Usually top. Some people chose otherwise.

noobinsf 

Where would be the more natural place for you shift? When I had thumbies on an upright bike, I mounted them "upside-down" so that my thumb would push the shifter under the bar (pulling to larger rear cog) and my index finger would pull it back toward me (releasing to smaller rear cog). It worked fine, but I'm not sure I would replicate it.

You're mounting these in the center of drop bars, right? That's what it looks like in the pics. You may have to leave a little extra cable/housing on the initial installation to try out a few different positions.

Did you rule out bar-end shifters?

vtchuck

I’ve used them other bikes…. Not a big fan. Although the Suntour’s are nice. I usually ride with my hands on the top of the levers or on the flats

vtchuck

Yeah looks like that’s gonna work

tricky 

Yeah, thumbies are usually on top.

You didn't ask for a discussion around alternative shift option, so just ignore this question if you'd like, but I am curious: Since you spend a lot of time on the hoods and tops of the bars, why not brifters? Thumbies will lessen the amount of real estate available on the top of your bars. If you are wanting to stick with friction, I believe Gevanelle shifters can be run in friction mode.

clubman 

I've never used (or seen) thumbies with that much throw out front, especially on a drop bar. I don't see it working? You tell us though.

ofajen

I know you have the thumb shifter mounts and they would probably best go on top, close to the stem clamp. If it were me, I’d go with stem shifters, leaving more bar available for hands while keeping the shifters in that area and handy. I think IRD makes a stem shifter mount that would work with those levers, but I have big old Schwinn stem shifters and the cheapo Sunrace shifters, both of which work just fine.

Otto

rossiny

I am going to try a drop bar conversion on my trek 930. Seems like I can use this, and just use my thumb shifters. , just need the brake levers. !

Frkl

I have put Shimano thumb shifters on a number of my drop bike equipped bikes. There are Deore and XT thumb shifters up to 7 speeds, and these have an 8th click if you need them, but work great in friction.

The Deore shifters have steel clamps, and these can be bent and filed to fit a drop bar, if you use a longer bolt. The XT shifters have aluminum clamps, but you can put an XT body on a Deore clamp.

There are also some lower end Shimano thumb shifters that use the same steel clamp as the Deore, so you can either use these or scavenge the clamp.

But also, a mountain bike thumb shifter has a 22.2 mm clamp diameter, and this is the diameter of a 1 inch quill stem. So you can mount them as stem shifters if you want.

mechanicmatt

I've done this a couple times as well. I mounted them on top, a bit away from the stem clamp, basically where the bar tape would normally start/finish. Also to help with cable routing I have had good luck either just crisscrossing the derailleur housing or using old v-brake aluminum noodles to help point the cables down.

Whenever I am trying to find an ideal mounting spot I sometimes ride the bike a couple times without wrapping the bars so I can ride and adjust the shifter location. Good luck.

vtchuck

I'm the OP. Didn't realize this thread was still alive. I'm sticking with this set-up for a couple of reasons.... #1 I've got a good amount invested in the VO mounts and Diacompe shifters. #2 I have a 2 x 5 friction drivetrain...

Thanks for sharing ideas and experiences

Digger Goreman

I agree with those who counsel a ride and see approach. As an example: while my commuter is a straight bar mrb, my right thumb shifter is above bar. My recently removed FD thumb shifter was actually mounted on the front facing of the bar (to make room for an air horn switch. Because the FD was a simple three positions, it was convenient to push up, down or center. The take away: whatever works.

Frkl

Stick with what works and what you have, of course. I had the Shimano units on hand and was happy to be able to keep them in service.

Regarding positioning, I also put them right at the bulge to the clamp diameter. I stop the bar tape flush with the mount so they can actually be rotated without messing with the tape.