Installing a Rohloff wheel in the Milan GT

I have a fondness for Rohloff hubs, I’ll admit. I have one installed on our tandem recumbent, and one in the WAW. I purchased the Milan GT in November, and I’m the third owner. Apparently it started out with electric assist, I’m guessing a Bafang on the front, in place of a chain ring. Second owner converted it to a 10 speed in the rear, and two chain-rings in front, 34 tooth and 60 tooth. That’s a very big range, and to move all that chain I give up a lot, specifically gears 5 through 10 using the 34 tooth. Beyond gear 5 I’m nearly guaranteed to tangle the chain up in the derailleur.

So right now I only have 14 gears, and have this odd little shift rhythm: in the granny gear up front (I live in hilly country and climb 13% grades) I can go through gears 1-4, then roll both shifters back towards me, to simultaneously shift onto the big ring in front, and to the 36 tooth in the rear.

The Rohloff will give me 14 speeds, in precise 13% increments between gears. But the Rohloff range is much wider, and with the Rohloff the gear selection is indexed inside the hub, so no more messing with shifters trying to get the derailleur indexing correctly. Just some simple cable tensioners if you need to adjust, but I rarely have to adjust them once set.

For me one of the biggest benefits of the Rohloff is being able to shift gears standing still or moving. A slight back off of pedaling force just at the shift makes things simpler, and I’ve already trained myself while riding the WAW. Here’s a video I made that shows a panic stop of sorts; I was flying around the corner about 40 mph, and there’s a slow moving vehicle right in the road! No time to change gears, but with the Rohloff I just shifted when things were calmer…https://vimeo.com/164433986

And naturally one of the reasons I have always been attracted to the Milan is the ability to add the Rohloff. The rear wheel is attached to the velomobile at both ends of the axle and uses a quick release skewer, like most bicycles. (There are quite a few velomobile designs that use a one-sided mounting bolt for the rear wheel.)

The wheel attaches onto the hanger brackets situated at the end of a large U shaped metal piece, the chainstay. The lower end of the shock absorbers also bolt on to the chainstay. The front end of the chainstay is held in place on some vinyl bushings, and the bushings are on a bracket bolted through the floor.

Looking rearward. Shock absorbers mounts onto the chainstay
Upside down in the sling, the chainstay is removed. The gray tubes are the shock absorbers.

Unfortunately the torque arm anchor point (or called something like that) is not on this yellow arm, so I had to remove the chainstay from the velomobile, and weld on an appropriate piece.

I have been trying to get this maintenance sling figured out so it works more gracefully, but for now, just accept that I have the Milan upside down in a sling, and that it was easy to get it there 🙂

I use the yellow rolling stool in the background when working on the Milan this way

This is a much easier way to work on a lot of the things in a velomobile. I use that yellow rolling seat and wear a good headlamp! This was the best way to remove the chainstay. The photo below shows the Rohloff hub set in the drop-outs. Directly above the drop-out on this side is the torque arm for the hub. You have to keep that from rotating for the hub to function! So I needed to weld an arm onto the yellow chainstay, and I have a shoulder bolt that will work perfectly as the anchor point.

Yellow chainstay setting on the Rohloff hub and wheel.

You can change where this torque arm faces, and I felt that it should point straight up as seen here, this will be simplest to line up when putting the rear wheel into the velomobile. It’s a very narrow space to get a wheel and your hand in there!

PB010008
This is the rear wheel with aero fairing removed for service. Not a lot of room for your hands!

I looked around in my scrap metal bin and found a suitable piece of flat stock that was very thick and sturdy. Then I ground down the paint in the affected area on the chainstay, and welded my brace on (and very glad that I took my welder in for repairs back when I didn’t need it 😉 ) Cleaned up and painted, and ready to go back into the velomobile.

Brace has been welded on; this shoulder bolt will line up the torque arm nicely.
Welded on a brace to hold the torque arm anchor bolt. And had yellow spray paint that matched!
Looking down at the shoulder bolt, and you can see the ears of the torque arm above and below the shoulder.

Now I needed to install the shifter and selector box. On derailleur systems the derailleur and associated cable run to the right side of the rear wheel. The Rohloff selector box and cables run to the left side of the wheel. I cut the cables for the rear derailleur and removed the twist index rear shifter, and put a new Rohloff shifter onto the tiller.

Installed new cables and cable housings for the Rohloff (had to review the videos on Youtube again). Everything seemed fine and ready to move forward.

But here’s where I ran into the glitch; the thickness of the drop-outs, the width of the hub, and the limits of the standard chain tensioner mounting bolt meant I couldn’t get the drive cog and tensioner lined up correctly. Rohloff uses a chain tensioner that takes up slack in the chain as well as keeping tension, and is absolutely necessary if you have multiple chain rings in the front. The tensioner comes with spacer washers, so you can line things up well, at least typically you can. Unfortunately I need a special longer mounting bolt, so I’m stuck waiting for the longer bolt to arrive (and I’ll install a new tensioner, this one is used and the idler wheels are pretty tired.)

I need a special longer mounting bolt, so I can line up the tensioner and the cog on the hub.

So since I was stuck at this point waiting for parts, I decided to put the derailleur system BACK in, and run new cable and housing, so I could continue to ride while waiting.

However, when you install cables for a Rohloff shifter, they really mash down the ends of the cable, so it is very difficult to remove and then re-use those cables. So I decided to leave the Rohloff shifter installed, move it in toward the center of the tiller handle as far as it could, and then installed the derailleur shifter outboard of that!

P6050144
Rohloff shifter installed but not connected yet.

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