This is the journal of Benedict Beaumont as he travels round India on a Mororbike.

This is the journal of Benedict Beaumont as he travels round India on a Mororbike.

Saturday, November 19, 2011

What I have learnt about ... bikes

When I tried to wake Ambliss at Mahendranagar, she wouldn't start. The 500cc Enfields take a good kick to get going, I have to almost stand on the lever and jump, but today, no matter how hard I kicked, it just wouldn't turn over.

I tried for about ten minutes, the hotel porter tried, even the security guard came over to try, but none of us had any luck.

I checked the spark plug - it looked it a little dark, but I couldn't be sure if it was that or the battery. I didn't have a spare - I did have one but I gave it to Dan in Himachel and hadn't replaced it.

'Mechanic?' I asked hopefully.

'Yes, this way'. The hotel porter helped me wheel Ambliss a few streets away. As it was not even 8am, the shop was closed, but a few people gathered round to watch.

The hotel porter spoke to a few people, presumably to see if they knew when the mechanic would come to open up. An older man, pulled over on his bike, got off, hunched over the bike and started fiddling.

'Tool, tool', he asked. I got out my tin box of spare parts and gave him the spark plug spanner. He removed the plug, studied it awhile, frowned, then picked up a piece of wire on the floor. With a look of intense concentration he started scrubbing the contact points.

When he put the plug back in, Ambliss woke with one kick. He smiled, waved, and then headed off on his way.

This kind of encounter has happened a lot. When I am difficulty, there has been people to help.

But this time, I kind of knew what the problem was. I didn't have the parts to fix it myself, but I could feel my understanding, maybe even empathy, of the bike, increasing.

When I first started this trip, my knowledge of bike mechanics and maintenance was zero. I didn't know one end from the other. But slowly, over time, through watching, and sometimes working with other people, I am starting to get to grips with how to look after a bike.

When you first start, its a bike A whole entity. One big unknowable machine. But after awhile, you start to see as a collection of different systems and parts. They are all interrelated, but also each is a discrete part that can be understood, and if necessary replaced.

I am not sure if this is correct, but this is what i have learnt so far.

The chasiss or frame of the bike is like the spine, from which the other parts bolt onto, and can be if necessary removed. Some of skeleteton is replaceable, for instance the handlebars after I had my crash, but other parts, the forks, are absolutely integral and if they suffer damage then the whole bike is compromised.

The electrics are quite simple really. The lights and the horns run off a battery, that is charged by a solenoid. If there are problems with this, and Ambliss has a tendency to lose indicator lights on the dashboard, its as matter of pulling out the wiring and checking the contacts and the earthing is clear.

The engine works by fuel coming from the tank being mixed with air in the carburettor and then ignited by the spark plug. If the mixture of air and petrol is wrong, either too rich (too much petrol), or too lean (too much air), then the bike will loose power. This happened to me on Carmen, especially high up where there was less oxygen in the air. This can be adjusted by taking the carburettor apart and adjusting a needle inside. The choke actually makes the mixture more petrol rich, which is needed when you first start the bike.

The air that is used is drawn in through a filter in a box on the side of the bike. This cleans it of all the major particles of that are in the air, dust, sand and carbon. The filter should be replaced every three thousand miles or so, although in the polluted atmosphere of India, it is probably half of this.

The spark of the mixture drives the pistons in the engine. I haven't seen an engine taken apart yet, but this is probably the most valuable part of the bike, and is not an easy job to do. Dans bike Butch had some problem with the pistons according to Rajesh when he took it back, and is expensive to mend.

The engine must of course have plenty of oil in it. This is quite straightforward to check, a bit like in a car. There is a dipstick/screw which I check every day. When the bike is cold, the oil level is lower, but expands and becomes less viscous when it is warm. Ambliss burns oiil if she drives or accellerates much over 80km an hour.

The pistons turn the primary gear chain. I haven't actually seen one, they are all covered. However, it is essential that this is well lubricated, and so it is necessary to check and refill with oil every 1000 miles or so. To do this, you have to undo a little nut and see if oil dribbles out. Ambliss always leaks a few drops every night, but every mechanic who has seen her says that it is ok.

The gears move the primary wheel chain on different sized wheel cogs, a bit like a bike. I am not exactly sure how this works, but the larger the gear wheel, then the higher the power but the lower the speed. Again this is covered, but like the primary chain, it must be well lubricated, and it must be checked in the same way. The nut for this is on the other side of the bike to the primary chain.

The primary chain drives the wheel chain, which is the chain that goes to the back wheel. The chain should give about an inch of movement up and down, but over time often become loose.

When this happens, the chain must be tightened. I was confused when I first heard this, because the chain is made of solid links, and I could not see how to tension this.

The answer is you don't tighten the chain as such, you adjust the position of the back wheel. If you move it further away, then the chain will automatically get a bit tighter. This is done by unloosening the axle bolts, then adjusting a snail shaped metal plate on each side to push the axle a bit further away from the engine. I have seen and helped this be done a number of times but have not done it by myself yet. Its quite a fiddly job for the inexperienced mechanic.

The rear brake is worked by the right foot. This pulls a rod forward and back, which is attached to the rear break shoe, When you tighten a chain, it is also sometimes necessary to adjust the footbreak by tightening a bolt on the rod.

There is no fuel gauge, so you never know exactly how much you have left in the tank. There are two taps that come off the tank that lead to the carburettor, the higher or main tap, and the lower, reserve one. Twice I have run dry because I had set the tap to the lower reserve tank.

To create the first spark takes a huge voltage. The kick start sends a current down one side of an electro magnetic coil - to complete the circuit, a spark jumps to the other contact in the spark plug, and then ignites the petrol air mixture coming from the carburettor.

There are more systems or parts. The suspension, the front break, the clutch, the decompression, that I haven't figured out yet.

Learning about bikes has been a really interesting experience. Not just for the knowledge itself, but the actual experience of learning about it. Its been very practical, kinaesthetic learning. This is how we learn, breaking big things down into smaller things, learning each, bit by bit.

I really need a workshop, tools and probably problems that need to be fixed to turn this knowledge from a theoretical understanding to a practical, problem fixing ability to look after my bike properly.

So now the spark plug is clean and the bike starts a lot more easily. And my understanding is a little deeper.

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