Thursday, February 23, 2017

Avanti Inc 3: Alfine 11 Di2 Drop Bar Conversion Part 3

Finally, Part 3 of this project to upgrade the Avanti Inc 3 to Alfine 11 Di2 and road hydraulic disc brakes. In Part 1 and Part 2 of this blog post, all the new components were shown and prepared for installation. Now, all the components can be installed onto the bike.

Let's take a look at the new drivetrain first. New Alfine 11 Di2 hub with motor unit, with new rear 28T Gates sprocket and new 115T Gates CenterTrack belt.

Before: 113T red colour belt, with Chain Guard on the mechanical Alfine 11 hub

After: New Alfine 11 Di2 hub, with Chain Guard removed. The belt and Motor Unit are able to fit within the limited space with the use of the special 28T sprocket.

MU-S705 Motor Unit installed to activate the electronic shifting. Di2 wire connects to the port at the bottom.

Di2 wire runs discreetly behind the right side chain stay to Junction B

Using the Di2 wire tape to position the wire neatly

Using long chain ring bolts and spacers to adjust the position of the front chain ring, in order to get a straight chain line.

A straight chain line is necessary to prevent noise and premature wear of the belt

Drivetrain installed! Front 42T and rear 28T.

New gear ratios of this Alfine 11 setup. Due to the larger 28T sprocket (previously 24T), the whole gear range has been lowered.

With the drivetrain installed, the focus now moves to the braking system. Compared to the braking system, the drivetrain set up is easy. The reason is that the brake system needs to be assembled from scratch, as the brake caliper and brake levers are not pre-assembled and pre-bled at the factory like most flat handlebar hydraulic brakes.

Bleeding the hydraulic disc brakes is new to me as I have not worked on hydraulic brakes before. However, with the help of the ST-R785 Dealer's Manual and some help from friends, I managed to bleed the brakes properly. Prior to this bike, I also practised bleeding the hydraulic brakes on another bike. A good hydraulic disc brake bleeding kit is also necessary. The process is rather tedious the first time round, but once you get the hang of it, it gets easier.

Dealer's Manual for ST-R785

Left side of ST-R785. Only used as a brake lever with no shifting function on this bike.

Right side of ST-R785. The two shifting switches are used to shift up and down the 11 gears.

Mounted on the compact road drop bar. The hood is taller than normal road shifters, but not an issue.

80mm stem mounted

Alfine digital display SC-S705 mounted as neatly as possible.

Accessories mounted on the handlebar. Limited space due to the narrower drop bar compared to a normal flat handlebar.

New bar tape! Trying out this silicone bar tape for the first time. No adhesive means it can be reused many times, while it is also water resistant and non-slip for wet weather usage.

Nice grippy, rubbery texture, quite comfortable too.

New handlebar setup, with road hydraulic shifters.

Di2 wire between the digital display (Junction A) and Junction B is routed neatly along the rear brake hose. Shown behind is the DIY steering stabilizer.

Battery mounted on the downtube, below the bottle cage. Junction B is fixed behind the seat tube with strong mounting tape + cable tie. Tried and tested on the Dahon MuEX and Wheelsport mini velo.

Front hydraulic disc brake caliper, comes with Ice-Tech brake pads.

Not as sleek looking as the new Flat Mount standard, but works just as well.

Rear hydraulic disc brake caliper

Picture showing the new drivetrain. Clean appearance and maintenance free.

Full view of the bike. Converted from flat handlebar to drop bar setup.

An all-weather drop bar commuting bike, which is coincidentally also a great touring bike.

This project has finally been completed, and it was not an easy project. Although I had experience with setting up the Di2 system and the Gates belt drive system, installing the hydraulic disc brakes were new to me. There were no major issues or difficulties with this modification, just that it is tedious due to the many components that were changed.

At this point, the speedometer reads 2700 km, which is the distance traveled on the previous mechanical Alfine 11 hub. In about 1000km, it will be time to service the new Alfine 11 Di2 hub by changing out the oil inside the hub.


  1. First off, AWEOME conversion, and a truly epic documentation of your progress. I'm contemplating converting a 2017 BMC Alpenchallenge IGH 8 (Alfine 8 mechanical) to Alfine 11 Di2, and have contacted BMC to confirm that the frame is compatible, and Gates support have also been very helpful in giving me part numbers for the new front sprocket and rear sprocket I'd need. The question I have for you is about how much did this conversion cost you in total, and where did you source the gates sprockets?

    1. Gates sprockets can be found on Universal Cost would depend on your choice of components. Biggest cost is the custom Alfine 11 Di2 rear wheel, also from Universal Cycle.

  2. Great conversion! Any comments on the braking?

    1. Braking is fantastic. Strong and modulated braking in all weather.

  3. Hey,
    Great job!

    How is it now, still happy?
    I'm about to start converting a derailleur bike to di2 alfine, mainly for winter conditions. It'll be less clean (chain + chain tensioner), but still igh..

    1. No problem, but I have since upgraded to a Fabike C3, as you can see from the new posts recently.

  4. Hi Steve,
    I think I must have read your page quite a few times by now. I have no clue why it is impossible to buy Alfine DI2 drop bar bikes ready like this from a dealer.. so I guess I will also have to get all the parts and do it myself. I'm totally new to DI2, so I hope I'm getting the right stuff. For the battery I'm planning the BM-DN100, which i believe is the newer model. Display will be SC-MT800 from the Deore-XT series.. its supposed to have ANT+ and Bluetooth.. and a charging port. No clue though if the external battery can be charged using the port.
    Shifters and brakes will be the same.. My frame does not open, so I will stay with a chain instead of the gates.. I'm curious how it'll go.

    1. External Di2 batteries have to be charged by removing it and charging it on the charger.

    2. Thanks, I'll get the external charger then :)

  5. Hi, just wondering, is there a different brake lever you could use on the left side so you wouldn't have the redundant shifter there?

    1. I think there may be a left side shifter without the Di2 shifting parts. But it would be easier to just get it as a pair. You could also wire up the left side shifter as well, so that one shifter shifts it up and the other side shifts it down.

  6. Hi. Nice job there. How much those the bike weight? Thanks.


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