Motorcycle 101

Lesson 4 - Starting

Finally, you get to start the engine. Hooray. If you screw this up, you can put the bike in a hedge or yourself in hospital

  • Gears - pretty much all real bikes have manual gears. These are usually controlled by a foot pedal on the left - 1 down and 5 up. That is to say, from neutral you click once down to get to first gear. Clicking once up gets you back to neutral, twice up gives second gear, three clicks gives third and so on. Usually there is a light to indicate neutral.
  • If you can drive a stick shift car, you understand the principles.
  • If not: The basic idea is this - internal combustion engines work best over a small range of speeds, but we want to go faster and slower than this. Also, unlike an electric or steam engine, they produce no torque when stopped. So we have gears, to change speeds, and a clutch, to disconnect the engine from the wheels when stopped.
  • If you have an electric starter, you may want to start in first gear. If you have a kickstart, you probably want to start in neutral. If it's cold, a small bike may have a manual choke and you probably want to warm the engine up before riding off. Newer bikes may have interlocks to prevent you from starting with the clutch out, or in gear, or with the kickstand down.
  • Sit astride the bike. Turn on the ignition. Hold the front brake on. Hold the clutch in and work the gear lever with your left foot until the transmission is in neutral (the engine disconnected from the wheel) - the light should come on. Start the engine (with the electric starter or kickstart). Slowly let the clutch out, keeping the brake on. If you are in neutral as you should be, the engine will idle nicely. If you are not in neutral, the engine should stall as you have the brake on. If you are in gear, apply too much throttle, and don't have the brake on properly the bike may shoot forward and damage something, maybe you.
  • So now you have the engine running. If you need, let it warm up for a bit then push the choke in. Play with the throttle a bit, getting a feel for the noise the motor makes at different speeds. Practice stopping the engine with the killswitch or ignition, and re-starting.
  • Next step - moving off. Roll the throttle to increase the engine speed, while slowly letting the clutch out. You should hear the engine noise change and feel the clutch start to bite, and the bike should start to move forward. As the clutch stops slipping and the bike moves faster forward, roll the throttle back (slowing the engine) until you are moving at a comfortable speed in first gear, with the engine at about 3000 rpm (if you have a tachometer). The engine should be burbling evenly, not screaming (too fast) or choking and juddering (too slow). The key to changing gear is listening to the engine note.
  • To stop, roll back the throttle until the engine is going slowly, but still comfortably, then pull in the clutch and smoothly apply the brake. Then put the gearshift in neutral before releasing the clutch. If on a slope, apply the rear brake with the right foot while balancing the bike with your left foot on the ground. To stop the engine, turn off the ignition or killswitch, then put the bike in first gear. You can now release the brakes, swing out the stand and dismount.
  • Changing gear - unlike the manual transmission in a car, you have to work through all the gears when accelerating and decelerating. You can't skip from fourth to first, or stop at a light in third then quickly move away in first. The basic idea is to accelerate in one gear until the engine moves beyond its power zone, then pull the clutch while dropping the engine speed to match the roadspeed in the next gear, then pop the clutch out and accelerate in the new gear, repeating until you reach the desired roadspeed. Decelerating is the opposite - you slow the engine until it is below its power zone but still comfortable, then pull the clutch and blip the throttle, raising the engine speed to match the roadspeed in the lower gear, then pop the clutch back. This pattern gives the characteristic noise of a motorcycle race as competitors move up and down through the gears. Alternatively, when decelerating, you can maintain the engine speed with the clutch in, and reduce roadspeed by braking until it matches the engine speed in the lower gear.

    This shows the bike shifting up through the gears. If you are into graphs, that is. When the clutch is fully engaged, each gear selects a certain ratio of engine speed to roadspeed. So the system moves up a red line - more engine rpm, more speed. When the engine goes too fast, the power starts to drop off. Besides which, it's screaming and the tachometer is on the red line, meaning it's not a good idea to stay there - something will overheat and break. So you want to change to a gear that is better for going faster (but not so good for hill-climbing). The dotted blue lines show the engine slowing down (with the clutch in) until it's at the right speed to match the next gear. If you let the clutch in too quickly at the wrong speed, the engine and rear wheel will suddenly reach a compromise speed and you may cause a rear-wheel skid. Which may cause you to lose control of the bike, especially if cornering.

    This shows the bike shifting down rapidly. You are braking, and rolling back the throttle, so the engine speed moves down a red line. When the engine drops out of the power zone, you pull in the clutch and blip the throttle to increase speed to match the next gear. The engine spends most of its time in the power zone (allowing sudden re-acceleration if necessary), connected to the wheel, and very little time disconnected with the clutch pulled in. This is the kind of deceleration you would do if you are coming into a corner on an open road, or pulling behind a vehicle before overtaking it.

    This shows the bike shifting down in a more leisurely manner. Instead of blipping the throttle to match the next lower gear, you just let the bike decelerate on the brake with the clutch in until it matches. This is the kind of deceleration you would use coming up to a red traffic light, or a parking space - you know you are going to stop, and where, and it is unlikely you will need to accelerate. If you do, downshift and blip the throttle to bring the engine back to the power zone.

  • Clutch exercises 1: Position the front wheel against a 3-inch high kerb or large block. Follow the moving off procedure to drive the wheel up onto the kerb, then stop. Roll the bike back off the kerb, then repeat. You should be able to do this repeatably, without overshooting, stalling the engine, jerking forward, or overheating the engine.
  • Clutch exercises 2: Find a large box. Mark a line on the ground. Use the bike to push the box so that it stops exactly on the line

Next: Checking stuff