Friday, 1 June 2012

Why ride a recumbent?

This is a question that is asked an awful lot and, in common with many other simple questions, doesn’t have a simple answer, but a complex and multifactorial one. Most of us who ride recumbents have a quick answer since (IME) you get asked the question so frequently that answering it fully becomes tiresome. I wanted to take the time to answer more fully and in a more detailed manner. Then I don’t need to ever do this again…..

How did it start?
I had had a fairly nasty crash on losing the back wheel of my upright in a 20mph corner. I was in a stookie for 6 weeks and starting to go a little stir-crazy at the enforced not-cycling-ness. Me being me, I started moaning about this on an online forum and someone suggested trying out a recumbent. I tried, bought, loved and bought more recumbents. It should be added that I was left with a little osteo-arthritis in my left wrist after the break, so for a few years, riding an upright was impossible. It is now possible, but becomes very painful on rough roads. The re-training of muscles takes a decent amount of time when transferring to ‘bents: the first 3 months have marked improvements and decent progress is easily made; but, as with many other things, it is the last 10% that is hardest. The second three months on a recumbent, I found very hard: I was on a far heavier bike with reduced power and am a bad climber anyway so hills caused me headaches. Getting that last little bit that changed hills from painful to alright was a drawn out process. It is worth being aware of this in advance if you are planning to completely switch over. I would find the switch a lot easier now since I am cycling a lot less, so have less power to transfer and am less-used to being able to climb, but I was cycling around 200 miles a week at the time of some lumpy roads, so was fairly fit and strong.

Why do I continue?

So that’s the ups and downs of starting with its reasons contained. I now do over 90% of my mileage on recumbents and only really use my road bike if I have to. My preference is for recumbents without question. Let me break down the reasons that, for me, constitute the basis of the preference.

Comfort. Upright cycling distributes weight across three different areas: feet, wrists and sit bones. It also requires maintaining a fairly difficult position if you want to reduce drag. I completed my first 100 miles in a day ride on an upright & it is fair to say that almost everything hurt afterwards. I had sore feet, extremely sore wrists, tired arms, an uncomfortable back and my neck was in agony. This was all in addition to the very tired legs that I had. When I have managed similar distances on a recumbent, I have finished with only sore legs. On occasion, my neck has been a little sore too. To be fair, some people find that the neck position is very sore to maintain, so they buy neck rests. I find that unnecessary, but can understand the reasons. The neck-soreness is far less on my Fujin (with a very reclined position and, therefore, a sharp angle to keep the head in the correct position) than it is on my road bike, but is an issue worth being open about. The reasons for this reduced soreness are that the weight is far more widely distributed and the position doesn’t need muscle tension to hold. Furthermore, rear suspension is frequently built into the frames, which can be achieved fairly easily without robbing power from the pedal stroke. In addition to this, the seats are normally padded in some way. There is a huge spectrum of comfort from a full suspension, wide-tyred, soft-seated touring machines through to the full-on race bikes, but if you compare the least comfortable recumbent to the most comfortable upright, the ‘bent wins hands down. Comparing like with like is not a task worth engaging in, the difference is night and day.

Aerodynamics. Anyone who has seen adverts in the cycling press for road bikes will be aware that this is a big issue. Fewer people understand why and how. I’m going to go through some approximated and simplified bicycle mathematics to explain this a little further. On the flat, speed is roughly the product of power versus drag. Drag rises as a cubic of speed relative to wind direction. What that means in practice is a doubling of speed requires eight times more power to overcome the resultant drag. In cars, what has happened is that the focus has been largely on more powerful engines to overcome drag. With human powered vehicles, there is a biological limit to maximum power and the engine is stuck at something around half a horsepower. This means to make a significant difference to maximum speed, you have to change the amount of drag (or, more accurately, the CdA): you have to make it more aerodynamic. Recumbents are typically 25-33% more aerodynamic than their upright cousins and velomobiles save far more again. You can see from the earlier formulations that this saving will quickly become huge at speed. In practical terms, this means I can go a lot faster for the same power, or the same speed for a lot further. Until the road heads up and the physics become power versus weight and drag becomes less significant. In a flat, windy country like the Netherlands, the advantage of recumbents is huge. I stay in a hilly and windy area so this advantage is certainly reduced, but I still find that there is a significant advantage: I’m quicker over a given route. As another simple comparison, the land speed record for a recumbent is 83.66mph and the fastest speed ever recorded in the TdF is 72mph. The former speed was recorded by a part-time athlete on the flat. The latter was recorded by an elite athlete descending a mountain. That is to say that with every conceivable advantage (a far better engine and a several mile long downhill), the upright still cannot get close to a recumbent. Comparing like-for like….
Once again, the difference on the flat and downhill is night and day.
It is worth mentioning weight, however, when discussing the relative speed of different machines. Recumbents tend to weigh more than upright bikes when compared like for like. There are two main reasons for this: the manufacturing runs are shorter and the chains are longer. Being a small market means that the budget for R&D is going to be significantly smaller than for uprights. Some of these budgets could be spent on things like novel use of exotic materials, but the money is unavailable. Consequently, there is something of a block in making very lightweight bikes. The other issue is the chain. On a RWD bent, the chain will be roughly 3* as long & therefore weigh 3* as much. That really starts to add up in what is a fairly heavy component. That all said, there are some fairly lightweight bikes available just now & almost certainly more to follow. 6-7kg is certainly achievable if you have the budget!

Safety. I am being serious here! Most people tend to ask if it’s dangerous to ride when they see me on a ‘bent and for the life of me I can’t work out why they would think it is. I have a theory around height and power and perceived safety, but the question is irrational and absurd. The first part is that you get given space when on a ‘bent that you don’t when on an upright. For the most part, Glasgow’s drivers are fairly good with cyclists (this is a relatively term, so perhaps should read less awful than many others), but on an upright, I am normally within touching distance of about half the cars that pass me in urban areas. This figure drops to well below 10% on a ‘bent bike and virtually 0% on a trike. In fact, on the trike, very few things get within 2 metres of me when passing. There are reasons for this, but all the same, the risk of accidental impact is hugely reduced. My other huge bugbear when riding an upright in traffic is that many drivers simply assume speed based on type of vehicle and don’t check. Many drivers see me on a bike and manoeuvre in such a way that indicates they think I’m doing about 10mph: which gets quite scary if you’re doing 25-30mph down a hill. I can only think of 2-3 occasions where a driver has pulled out on me in this way in many thousand miles of ‘bent bike riding and it happened twice on my 8 miles commute home last time I rode an upright. People worry about visibility too, but I find that visibility is a function of behaviour not size. Good road craft makes you visible, not being big. The only time it is an issue is approaching a t-junction where it is heavily parked, but leaning forward and inching forward until you can see you are clear tends to work.
The second aspect to the safety issue is the nature of the design and there are again two component parts to this. The first is the feet-first rather than head-first position. Whilst my advice would always be to avoid impacts in the first place, if you are going to have one, I’m guessing you’d prefer to hit feet first than head first. When I’ve not ridden an upright for a while & get on one, this aspect becomes terrifying clear when heading down a hill. Head-first with a centre of gravity above the wheels makes braking behaviour difficult and scares the hell out of me. Feet first with the centre of gravity behind the front wheel means that I can pull on the brake as hard as I like without risking of flipping & inspires a lot more confidence.
The other aspect is that I’m closer to the ground if I crash. This might not sound too great, but think it through. I’ve had two 30mph+ crashes from a recumbent (the first was down to my incompetence (trying to take a corner too fast) and the second due to a front tyre blow out whilst cornering) and I walked away from both with merely road rash and bruising. Don’t get me wrong, it hurts (a lot), but it heals fairly quickly and rarely requires medical intervention. I’ve only managed one crash at decent speed from an upright and broke my wrist (even though I was going a lot slower). So far this is a post hoc ergo propter hoc argument, but the key lies in the mechanism. If you go down on a ‘bent, you’re on the ground before you can react, you slide (removing skin, normally from the buttocks), then you stop. There is no significant impact. From an upright, you tend to get an arm down. Which tends to break. There is a significant impact. IME, you get the road rash too, but that tends to hurt less from an upright crash, but that might be the broken bones distracting you.

In summary then: comfier, faster/more efficient and safer. The question, it appears, is not “why do you ride a ‘bent?” but “why on earth would you not ride a ‘bent?”

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