The Shimano EW-JC130 Y-connector cable is used to connect two shifters to a Junction box or Systems Informations Display while using only one e-Tube port. It is generally used with the EW-RS910 junction - mainly because that specific junction only has two e-Tube ports.
The EW-JC130 comes in three different sizes to fit different handlebars and placement of Junction A EW-RS910, EW-JC200 or the EW-WU111 Wireless Unit. Refer to the images for an overview of the sizes.
Note that L1 corresponds to the Left shifter and L3 corresponds to the EW-RS910 handlebar junction.
It's optional - at a cost
Generally speaking, the Y-splitter is not a required component. You can actually connect shifters to each other and bypass the Y-splitter. This cleans up the cockpit area a bit, but it comes at the cost of decreased flexibility and the loss of 1 E-Tube port.
Personally I prefer not to use the Y-splitter for a cleaner look, but it all depends on the handlebar used and your own specific use-cases. There is more information in the EW-RS910 Junction installation guide.
Details & Specifications
|Shimano model number:||EW-JC130|
|E-Tube Port type:||SD50|
|Component series:||Non-series components NON (All)|
|Downloads:||DURA-ACE R9150 Dealer Manual|
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