Di2 DIY TIME TRIAL REMOTE SHIFTERS - PART 1

One of the great parts about electronic shifting is the ability to install multiple shifters.  In this case we want shifters at TT bars and the brake levers on the base bar.  While this is great, it is also quite costly with the Shimano Di2 Brake levers retailing at around $400 with no other alternatives on the market right now.

This do it yourself time trial remote shifter mod is nothing new, quite a few people have done this for bikes where replacing the brakes levers isn't possible, e.g hydraulic brake levers and my Shiv TT where I need the cable adjusters barrels in the brake lever.

This modification requires the following parts:

• SW-R600 Climbing shifter (Options are SW-R671 or ST-6770/6870 right shifter)
• 4 x 0.5m lengths of small electrical cable (I stripped a 4 core alarm cable 24AWG)
• 2 x 2 pin connectors (I used JST connectors used for RC cars)
• Cateye #169-9200 Remote Buttons
• 5 Minute Epoxy
• Heat Shrink
• Soldering Iron

Note these parts will provide control for the rear derailleur only.  I will install one button at each brake lever.  The left button for an easier gear, right button a harder gear.

If you want to install front derailleur shifting also, you will also need an STI or time trial left side shifter and some extra buttons.

I unscrew and disassemble the shifter body

Remove the main circuit board and dispose of the rest

I remove the cover and buttons from the circuit board

The circuit board is now ready for the remote button wiring

I Solder the 20AWG wires to the button contacts as shown below.  I stagger the wires to ensure the centre wires don't cross the outer contacts or the other wires where they could short out.

Shifting occurs when White & blue or Red & Black are connected via a remote push button.

At this stage I plug the E-tube wire into the module on my bike and test the shifting by touching the wire pairs together momentarily.  If it tests ok I seal up the unit with 5 minute epoxy.

I add some small JST connectors and heat shrink.  I use the male connector on one pair, female on the other to prevent potential mix ups when I assemble it later.

I have the remaining lengths of 20AWG cable with the terminals crimped and ready to go waiting for a set of Cateye #169-9200 remote buttons and the new base bar to arrive.