How can I tell that a left Shimano ST-6703 (triple crankset) shift lever is not actually a ST-6700 shifter (double crankset)?
Scenario: I have a 2010 frameset that came with a mix of Shimano 105/Tiagra/no-name components. The brakes were Tiagra (which were changed real quick to Ultegra). The "no-name" was a non-series Shimano triple crankset, since changed out to the Ultegra triple. The 105 was the drivetrain.
I've converted all the components to Ultegra, except for the shifters. Received them and took the bike into one of my LBS to have the bars changed (I like the traditional round shape), and have the Ultegra ST-6703 shifters replaced at the same time. Am having all the cables replaced also since it's been a couple years and many miles on the orig cables.
The shop called me a bit ago and insisted that the left shifter is a ST-6700 (front double shifter), instead of a ST-6703 (triple crankset). Fellow said that everyone in the shop verified that the left shifter is for a double, and that it only has "two clicks".
The box the shifters came in is marked to indicate the contents as ST-6703, however the enclosed tech sheets are ambiguous. One "Technical Service Instructions" says "ST-6703 Front DUAL CONTROL Lever" (doc # SI-6SE0A-001), and the other "Technical Service Instructions" says "ST-6700 Shimano Total Integration" (doc # SI-6SC0A-001). The two tech sheets from the Shimano web site are the exploded schematic/diagram and a TSI ST-6703/ST-5703 "Front Dual Control Lever" (SI-6SE0B-002).
Thinking about the "two shift clicks", to me, that seems right (for a triple). The ring you are in, and the other two. Stupid logic would indicate that a double would only have one shift click. Then again, remembering the 105 shifters ... you don't get from one chain ring to another by a single click. You have to "milk it". Maybe he is confusing the SRAM shifters for the Shimano ones? On a 105 and Ultegra shifter, should just a single lever throw change the chainring? Seems that on my Dura-Ace 7900, I have to use two swings of the lever to go from the small to large chainring, (but going down just takes a single throw).
Boy, I sure do miss the days of the downtube shifters. They were easy to adjust and use.
Can anyone familiar with the ST-6703 shifters help me? I am picking up the bike tomorrow, partially assembled, (they installed the rear/right shifter, but not the left one. I'd really hate to take everything apart to return it to the place I purchased it from, and all the hassle that entails. Maybe this shop just doesn't know what they are doing, (as far as triples go).
Is there any marking on the shifter itself to indicate the model number?
Thanks for any help you can proffer.