Tandem handlebars from flat to drop

Tandem with straight bars

The original handlebar set up.

In the last couple of years we’ve started using our tandem for longer rides and are looking at ways to make the bike more comfortable. We did some touring on it years ago, but now we’re riding 200k+ audaxes, where comfort is arguably even more important than when touring due to the time limit and limited time off the bike. As the stoker Erica tells me she’s very comfortable since we had a bike fit and she switched to a wide bullhorn bar with thick tape. With no need to steer she can easily change position on the bars or even let go or hold the saddle for a change when we’re going slowly. The tandem typically gives a very nice ride due to the long wheelbase, steel frame and 35mm tyres.

Flat bar issues

However, on my flat bars I’ve been stuck with a single hand position for an all day ride, which has caused some aches, particularly at the back of my neck and shoulders. I’ve never been able to ride no-handed and I don’t think it would be at all safe to do so on a tandem, as the stoker can shift their weight unexpectedly.

I don’t get this pain on my drop bar road bike even on much longer rides, so I wondered what the difference was. My current theory is the space between my hands. On the road bike this is at most 40cm, but on the tandem it’s always 50cm. I think this means my upper back has to work harder to bridge the gap and support my weight when leaning forward on the tandem. The usual advice for this is:-

Handlebars should be shoulder width apart (measured from acromion to acromion across the anterior chest) and comfortable.  Handlebars that are too wide may cause excessive trapezius and rhomboid strain leading to muscle spasm and pain.
roadcycling.com on Neck and Back pain

The other possibility is that the tandem simply takes more arm and shoulder strength to manoeuvre, but I think narrower bars with more hand positions are worth a try.

Drop bar conversion

With that in mind I’ve picked a drop bar that is 42cm wide. This should give me enough leverage for the heavier bike and plenty of narrower hand positions. It has a very shallow drop and short reach as I figured it wouldn’t make a huge difference to aerodynamics on a tandem. If I tuck down lower at the front it means I won’t be shielding the stoker from the wind quite so well. I imagine there are still gains there, but I assume a 20mm lower front position won’t be noticeably faster.

Hubbub adapter partly pushed into the Rohloff

Hubbub adapter partly pushed into the Rohloff

But there’s an additional complication to this set up. The tandem has a rohloff speedhub which normally needs a twist shifter. This is tricky to get onto drop bars. There have been quite a few ideas to make the rohloff work with drop bars, some of them rather expensive and fiddly to set up. I’ve gone for one of the simplest and cheapest options by putting it on an extension to the left-hand end of the drop. The extension is called a hubbub and has an expanding end so you can tighten it up inside the handlebar with an allen key. The shifter then clamps onto this as it would the bar. Having to reach down for this is another reason I wanted a small drop on the bars. I want to make it as easy as possible to change hand positions. I tried out Thorn’s Mercury a few years ago which, if I remember correctly, had a split bar with a twist shifter on the tops, near the stem clamp. The problem for me was that I don’t spend much time in the tops, preferring the hoods or drops. So reaching up for the shifter took some effort and I was putting a lot of weight on one arm to do it. Even on a short test ride this got annoying; on a longer one I guess it could actually become painful.

Putting it all together

Cutting a bit off the end of the bars so it's not so far back.

Cutting a bit off the end of the bars so it’s not so far back.

I spent a little under a hundred pounds on new kit, including Cinelli drop bars, Tektro RL520 Aero V Brake Levers, the hubbub adapter and SRAM bar tape. Luckily I already had a suitable stem leftover from a previous bike fit tweak to my wife’s hybrid. I held these up to the bike before fitting and did some rough calculations which confirmed that the hoods would be no further away from the saddle than on my audax bike. The bars were a little higher with respect to the saddle, but the only downside to this would be a slight aerodynamic loss and I could easily move them down later as there were still two 10mm headset spacers under the stem.

Rusty brake/shifter cables

Rusty brake/shifter cables

While I was doing the work I realised that the brake cables were getting a bit rusty, which is not surprising after at least twelve years use in all weathers. So I replaced the cables and outers, which was a bit fiddly but, even with the longer frame of the tandem, it cost less than five pounds. After I’d done this the rear brake seemed to have a lot of resistance in it compared to the front one. I can’t quite remember whether this was always the case, so I checked to see if anything was sticking.

Each part seemed fairly free and I could still get plenty of force through to the rear brake, so I decided it was good enough to try out there road.

I also added a small mirror to the opposite end of the bars though, being further inboard than the previous one, I’m not sure it will be worth it.

Test run

We took the bike out for a twenty km spin with a couple of steep hills. At slow speeds, especially starting off, I didn’t have as much leverage and fine control of the steering with the narrower bars, but once above walking pace they felt natural and I could even climb out of the saddle if I was careful. It was possible to hit my knee on the shifter, but didn’t happen often. What was not so good was that the shifter came loose and started rotating in the bar. The rohloff is quite easy to use, but each change does required a bit of force to get it to click. This soon became impossible without putting two hands on the shifter which was totally impractical and unsafe. So we stopped and found a suitable compromise gear to take us home.

Back in the garage I realised that the hubbub adapter wasn’t gripping the inside of the handlebar properly. I thought I’d got it as tight as possible with the shorter end of the allen key, the long end being required to reach down inside the adapter to the nut. If I had to epoxy the thing in it rather defeats the point of the hubbub adapter over a lump of wood or pipe. Online advice suggested that it just needed more torque, so I hunted around the garage for something to extend the small allen key lever. A bit of metal pipe would’ve done, but I was lucky to find an old suspension seat post. Miraculously, this is adjusted with an allen key in the bottom of the same size as the hubbub – 6mm. With a foot-long lever I could apply much more torque and it now shows no signs of moving. We’ve done a three-hour ride since and I’m confident enough to give it a go on a 220km audax at the weekend, which will be a real test of comfort.

New_bars

Finished and cleaned.

EDIT: After riding a 200 and 300km events (including one 1 in 4 climb) with this set up, I’m mostly pleased with it, but getting out of the saddle on a climb can result in  bashing my knee on the shifter unless I’m really careful. A sharp corner of it actually cut my knee on two occasions, so I may think about putting some tape over it or just stay seated.

Leave a Reply

Your email address will not be published. Required fields are marked *