Sunday, August 18, 2013

OT: Bicycles with Internal Gear Hub

Here in Toronto I see many decades old bicycles still on the road, which is amazing considering the really extreme temperatures we have. Most of these bikes have a 3-speed internal gear hub, invariably made by Sturmey-Archer. The longevity of these bikes and the hub tells you something about the reliability of the internal gear hubs. Naturally, as a gearhead, I am intrigued by these hubs.

What makes them so attractive is the simplicity and they make the bicycle look clean without clutter. Many also come with a coaster brake, which allows you to forgo the handlebar mounted brakes. This is the reason I love single speed/fixed gear bicycles. I ride the single speed/fixie bike to work exclusively for many years, despite having many other bikes. At times, I do wish I could change gears for the occasional hills I had to climb, or when I really wanted to go faster without pedaling like mad, and the internal gear hub seems like a perfect fit; at least on the surface of it.

There are some limitations with internal gear hub. The major concern for me is the extra weight compared to a single speed/fixie. In fact, the gear hub weighs almost as much as the frame itself, and I do not like heavy bikes. Also, 3 speed seems limiting, and the 7, 8, 11 speed variance are too expensive. Finally, they are not as easy to put together as a normal single speed hub. I wanted to try it, regardless.

4-Speed Road Bike - Canon 5D Mark II & EF 100mm f2.8L IS Macro. Click for larger.

A little while ago, I bought a 26 inch rim that came with a 4-speed Shimano hub, and a matching shifter. After reading obakesan's "On yer bike" blog post, I decided to put a bike together with this hub. Since I don't have any frames that can take the 26 inch wheel, and besides, the rim is in terrible shape, I decided to remove the hub and re-lace it to a 700c rim. Lacing the wheel is a time consuming task, especially truing the wheel. I didn't do a proper job by using spokes with too small a gauge. Heavy hubs like this should use very strong spokes, but that was all I had around the house.

4-Speed Hub - Canon 5D Mark II & EF 100mm f2.8L IS Macro. Click for larger.

Mounting the hub is relatively straightforward, but there are couple of things to watch out for. Some hubs, like this one, uses anti-rotational washer (or non-turn washers), and you need to use the right one for the dropout your bike has. My bike has a slightly downward dropout but the washer matched it perfectly so I don't need to buy a different one. There are ones for horizontal, vertical, and other variations. Do not omit this washer as it secure the hub from rotating. Another thing to watch out for is the reaction arm, for those hubs that come with coaster brake. I made a very bad mistake by trying out the hub without securing the arm, I almost ruined the anti-rotational washer when the coaster braked engaged accidentally. Be sure the reaction arm is secured before testing/riding. The coaster brake is too sensitive, in my opinion. It engages too easily.

Shifter - Canon 5D Mark II & EF 100mm f2.8L IS Macro. Click for larger.

When all was finished, the bike is heavier than I would like, and it's rear-heavy. My crank is a Campagnolo with a 53-tooth chain ring, which is larger than most on single speed bikes, but I like it as it provide me with more speed. It's mated to a 20-tooth cog on hub. This proved to be a good combination for me. At lower gear, it's good enough to climb hills but at higher gear, it can go really fast. I would like to have more speed choices in between, but for this experiment, I am quite satisfied. It works better than I expected.

The hub shifts instantly and very smoothly and almost noiseless. A very pleasant change from external derailleurs where even the best ones make some noise. I would love to try a 7 or 8 speed version, but the cost is prohibitive for me. An 8-speed gear hub costs around $350, and an 11-speed is in the $800 zone, which is too much for me.

This experiment is an eye opener for me towards internal gear hubs. I think I will ride this one as my daily commuter. At the same time I got the hub, I also got a Shimano dynamo hub for the front; lots of fun to be had. Now you know why this month there are so few entries for my blog :)


  1. :-)

    Sus the second hand and trashed bikes, I paid 100€ for my whole bike with the hub and changer. Sure its a nexus 7 (speed) but still.

    You mention weight, I wonder what the weight difference between a derailleur with its requisite brakes and the hub gear would be?

    Nice shots of the bike too.

    1. I think it's a great deal you've got for a 100 Euro. The hub itself costs more than that, provided it's in good shape.

      It's quite a bit heavier. The derailleur is actually not that heavy but the chain is longer but still, it's noticeable. The Derailleur with brakes and all that has distributed weight whereas the gear hub is one dense piece of metal in one spot at the rear. In riding, I don't notice too much difference.