Downtube shifters are shift levers mounted on the downtube of the bicycle. Not everybody will feel comfortable taking their hand completely off the handlebar in order to shift but for those of us who don’t mind doing so, downtube shifters offer the most minimalistic of gear shifting solutions.
Shifters on the downtube means taking one hand off the handlebar in order to shift.
Shimano Dura-Ace Downtube Shifters
These Shimano shifters have an “index” option on the right lever which means there are eight detentes or pauses signaled by audible clicks for each gear as the lever is moved back or forth. The left lever works the front derailleur and doesn’t have an index option. Rivendell is producing downtube levers without the index option for the real caveman in us all. The right lever can be used to change one, two or more gears up through all nine at one stroke. Kind of a nice feature. And the transfer of movement to the derailleur is super positive, mostly because there is only one short piece of housing at the rear derailleur and no housing on the cable to the front derailleur. Housing compresses and adds friction to the system.
Shorter runs of cable and no housing make down tube shifters more positive.
Only one short piece of housing on the rear shift cable.
I didn’t even realize it until I started reading a thread in Bike Forums about using downtube shifters, but to use these I actually reach across the downtube through the frame with my right hand in order to shift the front changer, the lever for which is on the left side of the bicycle.
Reaching through the frame to shift
One bike tourist I know uses Campy ergo shifters which means the shifters are incorporated with the brake levers. He carries a downtube shift lever and a piece of cable with him in case the ergo shifters fail. Keep in mind that in order to use downtube shifters, the bike must have brazed on attachments on the downtube. Those look like this:
Brazed on fittings to accept downtube shifters.
For those who appreciate a stripped down approach to touring and the peace of mind in having bike parts which are not failure prone, downtube shifters might be a consideration.
Pondero May 4, 2011, 9:33 pm
Totally with you. They also work and give a clean look to the bike.
Lovely Bicycle! May 5, 2011, 5:16 pm
Wait… Why do you need to reach through the frame with your right hand, can’t you just shift the front derailleur with your left?
Bike Hermit May 6, 2011, 12:46 pm
Exactly! It’s one of those unconscious things I didn’t even realize I did. It feels awkward to reach down with my left hand to shift, but not so with my right hand. I wonder if other people using downtube shifters do the same thing?
Donald Bybee May 8, 2011, 9:40 pm
If you ride the half step plus granny gear set up you sometimes have double shifts to make the next half step. This is where the down tube shifters work well as the shifts can both be done with the right hand almost simultaneously. I too feel uncomfortable shifting with my left hand. When I am riding my grip shift mountain bike I sometimes catch myself reaching for the down tube shifters without thinking.
Don
Sacramento, CA
Scheb May 15, 2012, 4:44 pm
Is there a way to fix a down-tube shifter on a frame without brazed on fittings? Is it possible to fix it otherwise?
Bike Hermit May 16, 2012, 9:36 am
Sheb,
Down tube shifters that clamp to the down tube are available, as are stem mounted clamp on shifters.
Anthony February 8, 2013, 7:04 pm
Great article! I just recently purchased a 1987 Cannondale SR500 and this is my first bike with downtube shifters. I’ve read through many forum posts, but the explanations seem to be more technical than I can understand at the moment.
If you wouldn’t mind explaining to be in the simplest of terms, I would greatly appreciate it! It’s a 6 speed with a double crank.
Thanks!
Matt November 25, 2013, 1:30 am
80’s Cannondales are the best! 88′ SR600 here. Love the downtube shifters.
Bike Hermit November 25, 2013, 7:10 am
Back when they made bikes to last!
Distinguished May 31, 2013, 8:52 pm
Too bad I flew & barrel rolled off my bike for braking & shifting simultaneously…
If you have down tube shifters, hold the bike strong with the left.
Mike Walsh August 5, 2013, 10:52 am
I find my downtube shifter slips when I’m climbing a hill in the lowest gear. I tighten it up as much as I can, but that doesn’t seem to help. Is there a way to improve the friction within the shifter assembly? A bit of duct tape?
Bike Hermit August 5, 2013, 1:07 pm
Mike,
I’m afraid I don’t have an answer since you said you’ve tightened it as much as possible. One suggestion might be to get some FSA Installation Compound and apply a thin film to the metal parts which slide over one another inside the shifter. The compound is made to increase the bond between carbon fiber and aluminum when installing seat posts. It’s a paste that won’t gum up or stick. Might be worth a try?
John R. Hogerhuis November 9, 2013, 1:31 am
I had this problem on an old Schwinn Le Tour II with suntour friction shifters. I had to bring a screw driver with me to tighten the shifter everywhere I went.
My recollection is that the shifter wire routing made a turn at an inflection point on the frame before it got to the derailleur. I lubed the shift wire at that point and the problem was solved.
I guess the frame flexing and vibrating was too much.
Henry Yen August 11, 2013, 12:38 pm
I ride where there’s lots of traffic and other hazards, and the ability of downtube shifters to shift through multiple gears almost instantly is highly valuable to me; I don’t think brifters will ever be able to do that (e.g. rapidly shift from, say, 5th gear to 1st gear, upon encountering glass in the road with a narrow shoulder, approaching a busy intersection on an uphill).
Bike Hermit August 11, 2013, 4:12 pm
Henry, That’s one of the other nice things about d-t shifters. Bar end shifters allow for that too….though they are still not as simple and clean as downt tube shifters.
Mike Walsh August 19, 2013, 8:52 am
Is there a good way to put downtube shifters on a carbon-fiber frame?
Bike Hermit August 19, 2013, 9:34 am
Mike, If the carbon fiber frame has cable stop bosses attached to the downtube the shifters will mount to those.
Mark October 8, 2013, 8:29 pm
I have a Tri bike with bar end shifter but use it for road riding to cause its the only decent machine. When heading up hill and having to downshift, I am not on the aero bars, and I regularly will use my right hand to operate both levers. I used to ride an old stem shifter and I think I used both hands on that, but I would operate both levers with the same hand at times. Its a no brainier when you are in a hilly area with lots of change, you usually need to adjust both gears, and it seems really stupid to take one hand off and switch one gear but it back on the handlebars and then switch the other.