Are you sitting comfortably? I am.

When I was building my list of components at the weekend, I almost completely forgot the seatpost and saddle. It's a bit odd, that, given that without those, the bike would literally be unrideable. I guess it's because there are so many more bits that are high-tech and shiny and futuristic-looking, that the thought of how I was going to sit on this bike slipped my mind slightly.

The importance of these can't be overstated, though. There's a very good reason we use the phrase "pain in the arse" to describe something we're not overly pleased with.

First, the seatpost. This is the long post which slides into the seat tube (see the diagram I posted last month) and has the saddle attached to the top. Setting the height of the seatpost correctly is really important. If it's too high, you'll overstretch your feet and legs at the bottom of each revolution, not to mention the problems you'll have getting on the bike in the first place! If it's too low (more common, from what I've seen) you'll find your legs bowing out the way a bit at the bottom of each revolution, and you won't be making most efficient use of your legs either.

The key to setting the right seatpost height is, so I'm told, to have it high enough that your legs are almost completely stretched out at the bottom of a revolution, but not quite. At least, that's how I've got mine set, and it feels good. If you've ridden a bike with its seatpost on the low side, trust me that it'll feel funny the first few times after you adjust it, but it'll be worth it and it's not too hard to get used to.

And so, on to the saddle. I've made a pragmatic but hopefully wise choice - I'm going to use the saddle I've already got on my Ridgeback. The reasons for this are, in order:

1. That saddle fits my bum perfectly (or vice versa). I've had six years of service out of it with a minimum of chafing. Some saddles - particularly leather ones, I'm led to believe - need quite some breaking in. Clearly that's not an option for me, since the bike won't be all built until early May and the ride is in June.
2. The seatpost fits my new bike perfectly. I was rather surprised by this, given there appears to be little crossover in standards between road bikes and other bikes, but it's exactly the right diameter.
3. I'll only ever be riding one bike at a time. Given how easy it is to remove a seatpost, having two seemed a little excessive.
4. The less money I spend on things I don't need, the more I can spend on things I do. That means a better bike!

The gathering begins ...

Good evening, everyone.

As I said last time, having been laid low and kept off my bike by a cold at the weekend, I put my free time to good use by picking out the components for my bike. Excitingly, they've already started arriving. The first part is the stem, which is quite fortunate, as it's the next part which has to be fitted.

When I had to go about choosing a stem, I wasn't quite sure what I was looking for. I've never owned a road bike before, with the loopy handlebars, and the only time I rode one I was aware that the riding position is rather different from the one you have on a hybrid or mountain bike. I was aware of being a lot more horizontal, stretched out along the frame, whereas on my current bike I'm very upright. Upright is probably better that way for negotiating city traffic and cycle lanes, but it's not especially in keeping with what I'm looking for with this new bike.

Fortunately, though, my current Ridgeback hybrid has been able to help me out. You can actually adjust the angle of its stem, so I was able to set it up at a similar angle to what I'd expect of a road bike. I sat on it in the sort of position I expect to on the new bike, judged how it felt, and made my choice from there.

I settled on a Cinelli Vai XL 100mm stem. The stem on the Ridgeback is 80mm, and felt just a little cramped for me, so I thought I should go for something a bit longer. Fit aside, as with all the components I'm putting on this bike (and as I did with the frame), I chose it based on a combination of price and reviews I read. It seemed to hit the sweet spot I'm looking for.

I've ordered the shallow-drop Cinelli Vai XL handlebars to go with it, but unfortunately they're on back order and won't turn up until towards the end of April. That may impact on the rest of the build a bit, as I won't have anything to attach the shifters to, but there's still plenty of time.

In the meantime, I've also got a seatpost and saddle, which I'll tell you about the next time ...

Anatomy of a bicycle, #3: Four candles

Good afternoon, everyone. I've been a little unwell recently, which has impacted my preparations for the ride as much as it has my writing here. But I'm feeling better now, and I've got a confession to make.

I may have slightly overdone it in the bravado department when I set out on this project. With the exception of the wheels, I was planning to put everything together myself. I got my frame, and I got the forks, and the logical next step was to get a headset and a stem, and to attach everything nice and snugly.

Which is where the problems began. There were points in the assembly instructions that required use of a hammer - which in my hands just normally means large lumps being taken out of something (occasionally me). During my background reading, I came across the phrase "catastrophic failure" more than once. Eventually (just about the time I saw the picture of someone sawing a bit off the top of a steerer tube),  I realised this is something you really don't want to go wrong.

Let's start with the forks. The forks on a bike are the steerable bits that attach to the front wheel. Where the two forks join in the middle is called the fork crown, and from there up is the steerer tube. The steerer tube goes through the head tube, with the fork crown nestled snugly against the bottom of the head tube. You attach a stem to the bit that pokes out of the top of the head tube, and you attach your handlebars to the stem.

So far, so good.

But if all you did was slip your fork through the head tube, and slap on a stem and some handlebars, your cycling experience would be jerkier than the chicken in a Caribbean restaurant. Every bump and undulation you went over would send your front wheel hither and thither.

What you need is a headset, to help join everything together nice and smoothly and make your bike rideable. A headset is basically a group of bearings at the top and bottom of the head tube, which allow the forks and steerer tube to turn smoothly and predictably.


"Fantastic", I hear you ask, "so what's so hard about slapping on a couple of bearings?"


What's so hard about is that a badly installed headset is almost as bad as no headset at all. Having previously ridden a very cheap bike with a very cheap headset installed very shoddily (I won't tell you where I bought the bike), I can vouch for this. It was completely unrideable. The various bearings have to be exactly aligned, at exactly the correct position relative to the head tube, with exactly the right load placed on them, in order to achieve smooth rotation.

That seemed like a big ask for a first-time bike assembler. The headset and stem are equally crucial to the structure of the bike as the wheels and the frame itself, so I figured it was best to treat them as such and leave that to the professionals. If I fit the drivetrain myself and I get a click-ick-ick-ick-ick sound rather than the smooth click I should when I change gears, that's too bad, but it's not going to result in the crunch-splat that a headset failure could.

In other news, I have picked out and ordered various of the other components I'm going to be putting on the bike, but I'll leave the details of that for another time ...

Anatomy of a bicycle, #2

Good afternoon.

Returning to the cycling theme, the bike-building will be starting soon, as I've just ordered my frame! After reading Robert Penn's "It's All About The Bike", I opted to go for a steel frame. A custom-fitted, hand-built Rourke frame is (ahem) slightly outside my budget, so instead I'm going for a Genesis Equilibrium 56cm frame. It's within my budget, I've read some rave reviews of it, and it's the bike of choice for the mechanics at a couple of local bike shops, so I think it'll be a good starting point.

[Aside: This will be the first time in about 20 years that I've had a steel-frame bike. The last one was a wonderful chromoly Peugeot BMX that I had up until I was about 13. After that, I went without a bike at all for the best part of 10 years. I often wonder what I could have done in that 10 years I was lost to cycling.]

So, that's the frame - a series of tubes welded together, in a roughly diamond shape. The best diagram I've found to explain the geometry of a frame is this one, which just happens to be annotated in Japanese:

• Top tube (トップチューブ): The topmost, horizontal tube, which runs from where the saddle would be to where the handlebars go.
• Seat tube (シートチューブ): The tube which goes down from where the saddle would be to where the pedals are.
• Head tube (ヘッドチューブ): The small tube at the front.
• Down tube (ダウンチューブ): The tube which runs diagonally from the bottom of the head tube to where the pedals are.
• Seat stays (シートステイ): The two tubes which run diagonally from where the saddle would be to where the back wheel is attached.
• Chain stays (チェーンステイ): The two tubes which run (almost) horizontally from where the pedals are to where the back wheel is attached.

Also annotated on this diagram is the fork, the steerable bit at the front which runs through the head tube and to which the front wheel is attached.

My first assembly job is coming up soon ... fitting the fork and the frame together, which requires me to read up on and familiarise myself with headsets. Expect to read something about them in the near future!

Off-topic: Mental health and debt

Although the subject matter of this blog is primarily bikes and cycling, tonight I discovered something which ties together a few disparate but related threads so beautifully, that I couldn't help but remark on it.

When I first thought about taking on this challenge, I was conscious that the money-raising aspect of it would be as difficult, if not more difficult, than the cycling part or the building-my-own-bike part. With the onset of crunchy credit and recessions and increasing unemployment and the like, I was well aware that a lot of people have a lot less money going spare for contributions to charities. I'm delighted to say that, in spite of this, my friends and colleagues have proved fantastically generous so far, as the totaliser at uk.virginmoneygiving.com/AlanGibson attests. You'll also hopefully be aware that all of the money I raise will be going to Mind, charity which provides help to the 1 in 4 people who experience mental distress each year.

However, I think we're probably all looking for ways to save money to a certain extent. One source I regularly use, whether it's finding the best insurance prices, cheap flights, voucher codes, you name it, is moneysavingexpert.com, and if you aren't already a subscriber to their weekly newsletter, I recommend that you sign up for it here.

Surveys have indicated that, of those who do suffer mental distress, almost half also have severe or crisis-level debts. For this reason, Money Saving Expert has teamed up with a number of organisations (including Mind) to produce a guide to mental health and debt, which can be found at:

http://www.moneysavingexpert.com/cards/mental-health-guide

Revelation!

Of course, it's not necessary to understand how something works in order to enjoy it. I myself was a frequent and satisfied user of such popular products as gravity, photosynthesis and electromagnetic radiation for many years without the slightest idea how they worked. But if there is one thing I learned from my good old granddad, it's that knowledge opens the gateway to even more exciting discoveries ahead.

And so it is with the derailleur gears on my bike. I've used them every day for years and years, and although I always knew there were cables and cogs and clicky sounds, and that the cables had to be tight and the cogs free of gunk and the clicky sound just a "click" and not a "click-ick-ick-ick-ick-ick", I didn't really know how they did what they did.

All that changed when I watched this video:

  

There's little more explanation required, but I'm going to anyway. To my mind, it is actually much like gravity. The lowest gears, both front and back, are the ones where the chain is closest to the frame (the "ground"). A spring in the mechanism ("gravity") exerts a force to keep the chain at this level.

Then, when you change up a gear, the cable pulls on the mechanism, slightly overcoming its force,  guiding the chain out to the next highest gear, with the tension in the cable keeping it there. When you change down a gear, you're letting some of the tension out of the cable, and the mechanism's tendency to drag the chain inwards will take effect.

The key, therefore, to getting nice, smooth changes up and down is to ensure the tension in the cable increases and decreases enough to allow the mechanism to move just enough to go up or down a single gear. The people who make these gear mechanisms are (thankfully) very clever, and build them so that if you adjust the cable tension to get a smooth shift from the lowest gear to the second-lowest, it'll all just magically work for all of the other gears too.

Anatomy of a bicycle, #1

Good evening.

One of the things I've always found most confusing when learning about bikes are the terms used for the various different bits and pieces. Even when I've read fairly detailed descriptions or watched tutorials that go into some depth, there's usually some fundamental unexplained term that throws me.

And I figure that if I've been thrown, then maybe so have you. Hence this series of articles, starting with something fairly simple but very fundamental indeed - the wheel.

Picture courtesy of Herr Kriss

The wheel is made up of the following parts, starting with (hopefully) the most obvious first:

• Tyre: That hard black rubbery thing that goes all the way around the outside.
• Rim: The round metal bit that the tyre is tucked into.
• Inner tube: The inflatable bit of the tyre, which sits between the tyre and the rim. The only bit of it you can see is the valve, more on which later.
• Hub: The bit in the middle, which attaches to the rest of the bike, and hopefully stays there.
• Spokes: The long metal rods which attach the rim and the hub.
• Rim tape: This sits between the rim and the inner tube, to protect the tube from any spiky or sharp bits on the rim.

One of the things I'm planning not to do in my project to build a bike is to build the wheels up from all the individual bits - I think they're just a bit too important for an amateur to have a go at. In all likelihood, you'll generally always buy or replace a wheel in its entirety, which will reduce your relationship with the wheel to the following:

• Inner tube valves: There are two different types of valves in common use: Presta and Schrader. Presta valves are longer, thinner and pointier (the valve in the picture above is a Presta); Schrader valves are more squat and wider. The only reason I mention this is that one time I bought an inner tube with a Schrader valve, and tried to use it as a replacement for a Presta one. It should have been obvious to me at the time, but the Schrader wouldn't go through the narrower hole in the rim. (Thankfully the other wheel of this particular bike did have a hole big enough for a Schrader valve, so the inner tube wasn't so much a waste of money as it was a prudent investment.)
• Broken spokes: This is pretty terminal. If one spoke breaks, it puts more stress on the others and you're likely to end up with the wheel collapsing. If you break a spoke, get off and push it home. Even if it is tipping it down and you're late for tea.
• Loose hub: The whole wheel should be held in place so that it doesn't "jiggle" to either side of the centre when you're cycling. I have on occasion had it happen that the hub's come a bit loose - you can feel and hear it, especially when you go round corners - the bike doesn't feel quite "with" you any more. You may need a new hub, or it may be possible to get your existing one tightened up, it all depends on how severe the problem is.

That's all for tonight!