Mallory, Call Me ( I’m not the same boy I Used to Be!) Part 2

So there I am doing my best to get a rugby player on a motorcycle through a gap made for a ballerina on point whilst my pal, oblivious to our impending impact is happily getting onto the line for the corner.  One of the more interesting nuances about motorcycling is a bikes reduced ability to be steered whilst under braking.  The retarding effect of the brakes has a tendency to stand the bike upright.  Of course if you are planning to enter a corner on brakes the modern sports bike is perfectly happy being steered, if you are planning it!  I am faced with an altogether different scenario.  Moving my focus from braking to just staying on the track, I glance by my focused friend and into the escape lane.  Thank goodness they put that there although it proves I’m not the only guy whose ambition has outweighed his ability.

 

Up through the rest of the track things start to settle down.  I’m concentrating more on learning the track than leaning on my mate.  In order to compete you have to be in the competition and lapses of concentration such as the one just passed are a surefire way of departing rapidly.  Next real obstacle is the hairpin.  Walking the track the night before it looked like a wall of death!  The videos I had watched never gave the impression of how 3 dimentional the track is.  The big problem here is getting off power and onto brakes smoothly enough to stop the back wheel locking whilst braking.  When you brake heavily on a bike the centre of gravity is thrown forward.  This has the effect of pushing the front tyre into the ground.  Novice motorcyclists find it hard to comprehend that the majority, if not all, braking effort should go through the front wheel.  Of course the other effect of this pitching moment is to unload the back tyre causing it to be much easier to lock, even under engine braking. A lot of the more modern machines have slipper clutches, which reduce the effect of engine braking.  I only have a cheap option, a smaller front sprocket that increases acceleration but decreases deceleration due to the resistance of the engine in overrun.

 

Cheap but effective, I am able to brake hard into the corner get my gear selected and ride around on power and in control.  However, now is not the time to be complacent.  Cracking the throttle just a little too eagerly brings some unplanned stunt riding.  The front starts to lift as the rear wheel forces its way underneath the mass of the bike.  Here is another centre of gravity trap.  If I do not get the wheelie under control the bike will continue to pitch up, all the time moving its CoG backwards.  The higher the front wheel the less power it takes to continue to the point where it gets expensive.  A quick toe on the rear brake is sufficient to create a pitch couple and bring the front tyre back into effectiveness.  A good thing too as no sooner have I accelerated, I am back on the brakes for a cheeky left right left flick flack known as Bus Stop.

 

Bus Stop is the second High Side Haven on the track.  Many a rider in their enthusiasm has opened the throttle just a little too positively here.  With the bike banked over the tyre takes the path of least resistance and squirms out from underneath cocking the rear end like a speedway rider.  This is good for speedway but not so good for track days, unless you are particularly adept.  Consequently most riders back off as aggressively as they had hit the power.  That’s where the tyre wants to make up for its earlier failings and throws its heart and soul into re-gripping.  We are now effectively trying to push the bike sideways at the speed we exited the corner, but it won’t go.  The down side is, you will, and so this happy union comes to an end and the rider is spat off far enough in front of the bike so as to be able to look back and see their faithful steed tumbling end over end towards them.

 

With all this in mind I approach the exit cautiously.  I need to get on the power positively but I also need to short shift before I exit the corner.  This seems more difficult than the corner itself but if I don’t manage it I get onto the all too short straight at the top end of the rev range in third and waste time and drive whilst fiddling to get fourth.  The trouble is that my bike, being road biased has a standard one down five up gearbox configuration so I need to get my toe under the left hand side gear lever whilst banked over…….to the left!  Catching my toe on the floor is yet another pitfall.  The best out come is a worn out boot but the worst is a broken ankle.  Sooner rather than later is the key so I can get back behind the screen for the maniac run down the straight, pipes bellowing my progress past the pit wall.

 

One lap nearly complete with just the entry into Gerrard’s to go.  Of course the difference now is I am entering the corner having sped down the straight.  The giroscopic effect of the wheels and the crank shaft are holding the bike upright but I can use this force in my favour.  One of the peculiarities of gyroscopic force is that a lateral disturbance to the giro (wheel in this case) acts at 90 degrees in the direction of travel of the wheel.  So I enter the right hander by pushing on the in turn bar.  The force is applied horizontally to the wheel into the turn but acts 90 degrees later on the top causing the bike to tip in.  It’s a well known technique but works fantastically well to turn the bike quickly.

 

Now the corner speed is really fast.  I have managed to complete my first proper lap of Mallory.  All the physics involved could not be further from my mind but their effects are foremost.  I need to repeat this, making mental markers of braking points, turn in points and apexes and it becomes an exhausting but amazing day.  I am so bitten by this bug that the MoT test due on the bike will be a day only type so that the bike can stay as close to track day configuration as possible.  That’s just one of many circuits running track days and having learnt it, I can’t wait to attack a few more, roll on next summer.

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