I personally purchased the SW-R9150, a single-button satellite switch for Shimano's 9150 series electronic Dura-Ace.
Until now, the tens digit in the product numbers for electronic groupsets was 7, but going forward it will be 5.
Since it's a single-button design, there are a total of two switches—one for rear upshift and one for downshift.
The installation has left and right distinctions, and
rubber mounting bases with two different radii are included for the mounting section.
This is originally a switch designed to be mounted on the drop bar section with a cable routed from the STI lever, and it's essentially a traditional satellite switch split into left and right units.
The fact that this is a satellite switch is particularly important to me because the key point is that it is "not a sprinter switch."
With a sprinter switch, the connector has a protrusion that prevents it from fitting into round holes.
(The image above shows the connector section without a protrusion)
↑This is the connector mounting section of the ST-6870, and the bottom hole has a notch to accommodate the protrusion avoidance. You can insert a standard connector into the bottom hole, but the sprinter switch connector only fits in the bottom hole.
The reason it's important that this single-button switch has a protrusion-free connector—allowing it to fit into round holes—is that you can directly plug it into the upper junction without going through (or even using at all) the STI lever.
I had been building an ultra-lightweight bike in a SRAM 10-speed front single-ring setup, but it occurred to me that upgrading to 11-speed with the next-generation Dura-Ace electronic groupset might actually result in a weight savings.
The RED 10-speed levers with the pads removed and the innards of the left lever completely gutted weigh 210g. With brake levers alone available in a left-right pair weighing 59g, adding the single-button switch pair and upper junction (21g total) brings it to 80g. From the 130g weight savings, subtracting the rear derailleur weight increase, the battery weight (entirely added weight), and the slight differences in shift cable versus electronic cable weight, I'm calculating that it should balance out overall.
I mounted the shift switch on the stem rather than the drop bar.
This is also an important point. On climbs, I want to grip the inside of the stem, so the traditional switch placement would be in the way. Being able to grip directly beside the stem while still being able to shift without moving your hand—this is the first time I've achieved that.
↑Side view
I routed the cable like this. The nominal cable length is 261mm. Since the bar tape is CatEye Shiny, which is extremely thin, the cable routing is visible through it.
Now I'm just waiting for the R9150 rear derailleur, and I've already adjusted the chain length. With the pedals already installed and the wiring complete, the only additional weight will be the rear derailleur. Currently at 4730g, breaking the 5kg mark is confirmed.
I've already confirmed that the single-button satellite switch works directly plugged into the upper junction with the RD-9070.
As long as the RD-R9150 doesn't have firmware that refuses to operate unless routed through the STI lever or using only the satellite switch, the only remaining task is mounting the rear derailleur and it's done.
Until now, the tens digit in the product numbers for electronic groupsets was 7, but going forward it will be 5.
Since it's a single-button design, there are a total of two switches—one for rear upshift and one for downshift.
The installation has left and right distinctions, and
rubber mounting bases with two different radii are included for the mounting section.
This is originally a switch designed to be mounted on the drop bar section with a cable routed from the STI lever, and it's essentially a traditional satellite switch split into left and right units.
The fact that this is a satellite switch is particularly important to me because the key point is that it is "not a sprinter switch."
With a sprinter switch, the connector has a protrusion that prevents it from fitting into round holes.
(The image above shows the connector section without a protrusion)
↑This is the connector mounting section of the ST-6870, and the bottom hole has a notch to accommodate the protrusion avoidance. You can insert a standard connector into the bottom hole, but the sprinter switch connector only fits in the bottom hole.
The reason it's important that this single-button switch has a protrusion-free connector—allowing it to fit into round holes—is that you can directly plug it into the upper junction without going through (or even using at all) the STI lever.
I had been building an ultra-lightweight bike in a SRAM 10-speed front single-ring setup, but it occurred to me that upgrading to 11-speed with the next-generation Dura-Ace electronic groupset might actually result in a weight savings.
The RED 10-speed levers with the pads removed and the innards of the left lever completely gutted weigh 210g. With brake levers alone available in a left-right pair weighing 59g, adding the single-button switch pair and upper junction (21g total) brings it to 80g. From the 130g weight savings, subtracting the rear derailleur weight increase, the battery weight (entirely added weight), and the slight differences in shift cable versus electronic cable weight, I'm calculating that it should balance out overall.
I mounted the shift switch on the stem rather than the drop bar.
This is also an important point. On climbs, I want to grip the inside of the stem, so the traditional switch placement would be in the way. Being able to grip directly beside the stem while still being able to shift without moving your hand—this is the first time I've achieved that.
↑Side view
I routed the cable like this. The nominal cable length is 261mm. Since the bar tape is CatEye Shiny, which is extremely thin, the cable routing is visible through it.
Now I'm just waiting for the R9150 rear derailleur, and I've already adjusted the chain length. With the pedals already installed and the wiring complete, the only additional weight will be the rear derailleur. Currently at 4730g, breaking the 5kg mark is confirmed.
I've already confirmed that the single-button satellite switch works directly plugged into the upper junction with the RD-9070.