Thursday, October 21, 2010

Storm in a H cup

Certainly they had a go at wrenching it off
Finally, a few moments to work on the bike today. Boy does it take a long time to complete the work when you only go at each stage bit by bit. The frame came with a set of FSA cups still fitted, but they looked pretty beat up. I guess the previous owner had tried to remove them, but without the correct tool. Cups are an integral part of the headset of the bike, this is for want of a better description the linkage between the bike and the forks that hold the wheels and the steering bars. Without them, you are going to have a pole that rattles around inside a tube. It is quite a clever bit of engineering linkage, and overtime has evolved different methods of holding the fork steerer to, eventually, the handlebars. The setup we are going to use is a threadless headset, I am not going into the details, of stuff you can look it up on Wikepedia and several other websites if you are interested, but the whole process is, in theory, quite simple.

not a wing pylon, but a cup remover inserted into the steerer column
First you need the correct tool, the cups are simply slotted in the frame, so you could rip them out with a strong arm and a pair of pliers, something I think the previous owner had tried. As alternative, you could tap them out using a hammer and and an old screwdriver. It would be a slow job as you would need to go round moving each side evenly to prevent the whole thing getting wedged. Otherwise buy and cup removal tool, or borrow one. The cost a tenner, which isn't so bad. It's about the same amount you would pay the workshop to do the job for you. The tool is simply a split tube that fits in the steerer column, but the split will flange out to rest on the internal face of the cup to allow you to tap it out with a hammer. How simple is that? Feed in, tap and off it comes, the repeat for the otherside.

Two removed H cups
Now the problem comes in not planning for fitting the otherones on to the frame. Simple investigation of the the cup and the frame reveals, that these are going to have to be set level and true. That means, you guessed it, another specialist tool. Simple enough to build, as it is only two flat plates on a screw column with some method of pressing both cups onto the frame e.g. a wingnut. The parts though probably cost as much as a secondhand precision engineered one. So I will need to look into that for the future, and see if I can borrow what is needed to get off the ground sooner. In fact, borrowing appears to be the order of the day as, I am unsure of the quality of other parts of the headset assembly attached to the existing fork. My first idea was to replace the fork with a better one, sooner than later, but pennies predict that this will not be happening any time soon. So I will try and not change, star nuts and crown races, but you never know. See what happens when I have a go.

Monday, October 11, 2010

Fitness to survive

I went out on my old hand me down "Tesco Special" yesterday and found that I was doing a lot more on it that I have been, despite not being able to ride out much this month. My hill climbing was a whole lot better and my approach on trails was a lot faster (due to improved fitness and some reflection time on technique). I even managed to practice clearing some kickers to help with clearing drop offs without stopping.

I was feeling pretty pleased all round having completed two circuits in the time that it normally takes to do one. So riding home across the park all full of the joys of autumn I had a major crash. There is a nice "gentle" slope with a "small hop" into a wide open park space. It is normally a matter of pushing the bike out and then down to the ground and away you go. Not this time as a combination of factors brought about my downfall. They do say "Pride before the fall", and I was probably a little over-relaxed by the familiarity. This allied to the extra speed I carried down the hill, because I could see the crosspath had no dog walkers and also I was in a good mood, resulted in my downfall.

The bike literally flew off the lip, normally about a body length around 2m (5-6ft) before being planted and pedaling off at high speed,but this time the bike shot twice that distance and still landed sweetly. Then I found myself planting my head and face into the soft green grass with the bike following for several revolutions. I stopped rolling aware that my helmet and elbow pads had just saved me from a crushed skull and broken elbows, and wishing that I had worn knee pads that day. Nothing broken, but a lovely sheen of blood from the top of my thigh, a slight flesh wound, I was fine.

I took a look at the bike. The handlebars had wrapped round through 360, the front wheel did not line up with the handlebars pointed, the seatpost had moved, chain obviously off the cogs, and more tellingly the front brake set were locked below the wheel rim. Not that the back looked to have fared much better. I went back to check on the landing area, and there were two nice neat tyre marks for the landing point. Followed it has to be said by the scrapes of various body and bike parts coming into violent contact with the ground.

Now you may be asking what this has to do with evolution and bike building. Well the first lesson is that at a certain point the design really can't take the beating the environment dishes out. I'm fitter and stronger than when I started riding it. Initially, I thought I would just be joining a few moderate cross country rides, which this is fine for. In stark contrast my friends felt that belting down single track and throwing bikes off steep slopes and over jumps would be more fun. I improved to meet the challenge, the bike couldn't. My fitness to survive is assured as long as I jettison my symbiote and find something more resilient. That would be the P3 then.