Sunday, December 11, 2016

His & Hers Folding Bikes

A few years back we converted from a timing chain to a Gates belt drive on our tandem. For those who don't know tandems, the rider in the rear generally is pedaling a traditional drivetrain with chainrings, chain, derailleur and rear cassette on the right, but also rotates another chainring on the left side of the bottom bracket that is connected by another chain to a matching chainring turned by the front rider's crankset. The Gates belt conversion replaces that front-back linkage with a carbon belt and two matching rings. Here is how it looks:

This belt drive is great! It is light, quiet, clean, and maintenance-free. The only improvement would be if we could somehow do a similar conversion for the other chain, but that would involve modification of the bike's frame, and replacing the rear wheel hub with an internal gear hub (IGH). The best of those hubs (Rolhoff) are very expensive. In addition, IGH is typically heavy and roughly 10% less efficient that a regular chain drive. Still, it probably would work well on a bike meant for lower speed use, like commuting, casual trail riding, or perhaps even touring. I tucked that idea away in my mind.

A year ago, or maybe it is two, my wife Kathy took her second recent fall while riding her road bike. A few years earlier she tore some shoulder ligaments; the last time she broke her wrist. Back when we were in grad school, she rode her 10 speed everywhere, but since we returned to cycling about 18 years ago, she has not managed to regain her old confidence. These two accidents made matters far worse. She thought maybe she would be more comfortable in a more upright position, perhaps with flat bars. I dutifully converted her road bike to something of a hybrid with flat bars, flat pedals without clips, and a twist shifter (not such an easy project, by the way) but she was still very anxious when riding. It wasn't enough of a change. She thought that MAYBE fatter tires, a lower top bar and a lower seating position might work, so that idea also got tucked away in the back of my mind.

One of the things we would like to do over the next few years is to do long road trips in the US. I have long wanted to share some of the places I experienced on my bike tours in the west (Colorado, Wyoming, Montana, Idaho), and there are plenty of compelling areas of the country that neither of us has visited. It would be terrific if we were able to bike in many of those places, too. Kathy has no interest in multi-week bike tours like the ones I have done, but if we could somehow bring the tandem along with us... OK, that idea went into the brain warehouse with the others. 

Over the summer I stumbled across, or maybe deliberately started googling, foldable bikes with belt drives. Most all folders have wider tires and low top tubes that would appeal to Kathy and, it turns out, some even have belt drives coupled to wide-range internal gear hubs. I was shocked to find that some of these bikes are very reasonably priced. In August I found Downtube Bikes ( which has just such bikes for $699 each. These bikes take about 30 seconds to fold and unfold. Really. Watch the video.

That URL was saved away for future consideration.

While we were in the UK (primarily Edinbugh, plus a few days in London and Bath) for a non-bike vacation in October, I was impressed by the number of folding bikes zipping around. We were getting around on foot and public transportation, and I found that bikes with wheels up to 20" were accepted on trains and buses. Huh! A pair of folders would be more portable than the tandem and give us some options for bike travel on our future trips.

By now, you know where all this is going. Here are our new bikes:

We started with just one because I wanted to be sure that Kathy would be comfortable. At this point she has only 5 hours or so on it, but is already much more comfortable that she ever was on her road bike. I myself love it. I had to make peace with the idea that I was going to be travelling significantly slower than on a full-sized, chain-drive bike, but once over that hurdle, it has been great fun. 

A couple of things I would share: 
  1. These particular bikes from Downtube when new have an issue with the plastic dust seal between the rear sprocket and the hub. The bike's 22 tooth sprocket rubs against the dust cover leaving you with the first impression that there is something seriously wrong with the bike. I remembered reading something on the Downtube web site about it, though, and the suggested fix worked fine. All you have to do is to back-pedal for a few minutes to wear away the lip of the hub's dust seal and you are good to go. Coasting and freewheeling down a few hills finishes the job.  
  2. Belt tension is important, and the belt was overly tight on both our bikes. Gates has phone apps available for both Android and IOS to check belt tension.
  3. The Shimano IGH units, including the Nexus 8-speed hub on this bike, loosen up for improved shifting and easier pedaling over time. We have noticed the improvement in the short time we have had the bikes, and apparently it will continue to improve over the first 1,000 mile or so.