New Year Apparel Sale—Save 25% or More

Shimano Ultegra Di2 FD-6870 Front Derailleur

Shimano Ultegra Di2 FD-6870 Front Derailleur
Sale $140.07$205.99 32% Off

Item # SHI0658

Select options
  • Select options
  • Gray, Braze-On ($140.07)
  • 100% Guaranteed Returns
  • Free 2-Day Shipping
    on orders over $50

Item # SHI0658



The Ultegra Di2 FD-6870 Front Derailleur features a self-trimming function, which basically means that the internal CPU knows what gear your bike is in and thus where your front derailleur needs to be in relation to the chain. This works in conjunction with the "programmed motion" of the derailleur. Once the high and low limits are set, it moves onto the big or small chainring, and then re-centers itself. Once and for all you are rid of chain rub on the cage plates. Additionally, the 6870 shifts quieter than the previous 6770.

Although the Di2 system still has an unmistakable "electronic" look, the profile of the 6870 is more slender than the previous 6770 and offers a more streamlined appearance. As electronic components are continuously refined, we expect this trend to continue.

The Shimano Ultegra Di2 FD-6870 Front Derailleur comes in Braze-On, 31.8mm, and 34.9mm configurations. It's designed to work with both standard and compact gearing for double-chainring cranksets. The wire kits and other associated electronic components are sold separately.

  • E-Tube compatible for programmability
  • Compatible with both standard and compact chainrings
  • Wires sold separately

Tech Specs

[body] aluminum, [cage] aluminum
Claimed Weight:
155 g
Recommended Use:
Manufacturer Warranty:
2 years

Size Chart


Di2 Reference Guide


Note: This reference is meant to be used as a guide for creating a Shimano Di2 drivetrain package. For further assistance please feel free to give us a call.


Battery and Wires:

Our Shimano Di2 packages are built for three standard configurations based on battery location and wire routing. First, you'll need to determine if your frame uses an internal or external battery mount, and whether the routing is either internal or external. Below is a guide for which battery, charger, mount, and junction boxes are required for your configuration.

Battery and Wire Configurations
 BatteryBattery ChargerBattery MountJunction AJunction B

External Battery

w/ External Routing

SM-BTR1 SM-BCR1 SM-BMR2 SM-EW90 A/B 3/5 port SM-JC40

External Battery

w/ Internal Routing

SM-BTR1 SM-BCR1 SM-BMR2 SM-EW90 A/B 3/5 port SM-JC41

Internal Battery

w/ Internal Routing

SM-BTR2 SM-BCR2   SM-EW90 A/B 3/5 port SM-JC41

Battery Mounts:

The SM-BMR2 battery mount is available in three configurations -- Long External, Short External, and Long Internal. Both Long versions are to be mounted using the bottle cage mounts, while the Short version is designed for Di2-specific frames with either a chainstay or down tube mounting location.



There are two junctions needed for completing your Di2 build -- A and B.  Junction A, SM-EW90, is located at the handlebars and available in both three- and five-port options. The three-port option is intended for standard shifting with a left and right hand shifter. If you have the intention of using Shimano's satellite sprint shifters, or a combination of time trial shifters and shifter/brake levers, the five-port junction box will be the necessary selection.

Depending on your frame specification, Junction B (SM-JC40 or SM-JC41) is located either internally or externally at the bottom bracket area. Accordingly, SM-JC41 is designed for frames with internal wire routing, while SM-JC40 is intended for external wiring options.


E-Tube Wires:

For your convenience, we've created wire packages for your Di2 build kit in the sizes Small, Medium, and Large. Below, you'll find which wire lengths are included in each kit. Additionally, we've recommended a kit size based on your frame size.

 E-Tube Wire Length Chart
Down Tube Wire 700mm 750mm 950mm
Front Derailleur Wire 300mm 350mm 400mm
Rear Derailleur Wire 500mm 550mm 600mm
Battery Wire 300mm 350mm 400mm


 E-Tube Wire Frame Size Guide
Frame Size  47-52cm 53-56cm   57+cm

Please Note:

E-Tube Wire length suggestions are an approximation. 

Reviews & Community


Write a review

    Add a:
  • Photos
  • Videos

No file chosen

Rather attach a photo from your computer?


Only jpg, jpeg, png, gif or bmp files please.

Submit ReviewCancel

can i use this with a 10 speed configuration or will it only work with an 11 speed configuration? Thanks

This is the NEW 10 speed Model. It replaces the 6770 I guess. I just replaced the Rear Derailleur w/6870 and still using the Front 6770.

Packs a punch!

  • Familiarity: I've put it through the wringer

This derailleur is smaller that I thought it would be, and I was always jealous of my buddies, and competitors when I would hear the "zziipppp" of the shift from small to big ring. Now I get to hear it for myself and it is music to my ears. No longer do I need to dislocate my left wrist in shifting, now it is as eazy as clicking a button!

Robot Bike

  • Familiarity: I've put it through the wringer

Whiiiiiiir Zip Beep Boop Beep

1600 miles on this drivetrain and not a single issue or adjustment needed. Every shift has been flawless, and barring any unforeseen circumstances, like a crash or some good old fashioned garage or transportation mishap, I fully expect go 6000+ miles with no issues. The only drawback I can find, and this is totally a personal preference, but I sort of miss the mechanical drivetrain for no reason other than the simplicity of pushing a lever which pulls a cable which moves a derailleur. I would argue that the Di2 lacks tactile feedback when shifting, but that is just me nitpicking. I rode the battery until it completely died just to see what would happen. At about 1300 miles (this includes plenty of playing with the new group, shifting just to hear the sounds and show off the auto trim) The battery died on my 18 mile commute to work one morning, first the front derailleur refused to shift, after a few more shift button clicks it did shift down into the small ring, and I had about 30+ shifts of the rear derailleur before the system became unresponsive. So 1300 miles, I think it is safe to say a rider would need to be quite negligent to run out of power on accident.

If you want to incorporate the Bluetooth communication so you can firmware update and change shifting settings with your iPad, you will need an additional 150mm eTube wire, and the Di2 Wireless unit -

Di2 all the way

  • Familiarity: I've used it several times

It's hard to talk about one piece of an electronic drivetrain independent of the rest, but I shall endeavor to do so.

Ultegra is sweet spot for price and performance and the Di2 version is really no exception. The looks are polished if somewhat utilitarian - none of that Campy flair here. But the real concern here is shift quality and that's where this derailleur really shines.

Simply put, this system does not mis-shift. Ever. Even those tough jumps up to the big ring are handled quickly and efficiently. The responsiveness is confidence inspiring to say the least.

When Ultegra can be this good why bother with Dura-Ace?

Avg. ride time: 1h 46m per week
  • Average ride time is based on Strava activity over the last 3 months. Give your reviews credibility by connecting your account.


  • Familiarity: I've put it through the wringer

In the word of front derailleurs, the Ultegra Di2 front derailleur is pretty remarkable -- precise, fast shifting every time. I've used it on gravel bikes, road bikes and aero bikes, in each application it has impressed.



  • Familiarity: I've put it through the wringer

I purchased a bike with Ultegra Di2 about a year ago. It was my first foray into electronic shifting and it's just flat out reliable. The batteries last forever and you get quality dependable shifting. In the year that I've had it, I have had zero hickups.

Sticking with it!

  • Familiarity: I've put it through the wringer

Building a new bike is always exciting and it's always tempting to try new things. The drivetrain decision was particularly easy this time however, after my previous experience with Ultegra Di2. The light weight and sexy lines of the Dura Ace Di2 group are indeed tempting, but for the cost you can't go wrong with the Ultegra. I have had exactly :::zero::: issues with my previous group other than problems I have inflicted (read: derailleurs are not-crash-proof). This also makes the Ultegra a great option if you race, where close quarters and periodic pavement sampling are a fact of life.

Avg. ride time: 27m per week
  • Average ride time is based on Strava activity over the last 3 months. Give your reviews credibility by connecting your account.

best front mech ever

  • Familiarity: I've put it through the wringer

I've used the 10speed iteration for a long time and this is more of the same. It's great shifting every time. You have to love it.

Outstanding Technology and Operation

  • Familiarity: I've put it through the wringer

This front derailleur is part of a complete Ultegra Di2 system. It works excellent. Shifts from the small chain ring to the large one are so smooth it's like an automatic transmission in a car. Shifting down to the small chain ring is very smooth also. Follow the Shimano Dealers Manual (available on line at for install and set up. With a mid level of bicycle maint. experience it can be set up to operate smoothly and reliably.

Avg. ride time: 39m per week
  • Average ride time is based on Strava activity over the last 3 months. Give your reviews credibility by connecting your account.

I ordered the 6870 front derailleur knowing it was backordered, is there a time frame when it will be shipping out?

Hey Eric, Typically most back ordered items ship within 2 weeks of purchase day unless other wise specified. I will be in contact with you through email to give you the exact ETA of the items arrive.