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.
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.
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.
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:
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.
