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Are You a Sidecar Driver?

Updated: Dec 24, 2018

There are as many different approaches to racing as there are racers but there are two extremes that stick out in my experience. First, there is the analytical racer and then, the somewhat opposite, adaptive or reactive racer.


The analytical racer can tell you every detail of each one of their practice laps, where the cracks in the asphalt are, exactly where they start braking, who is in front of them going into the turn and what the suspension is doing at the same time. They know exactly what their

jetting is, how many ounces of fuel it takes to run a lap on every track and every other little detail they need to know to keep the bike and themselves running at maximum. Everything in their world has definition, dimension and a clear purpose. It's black and white all the

time; there is no gray. They are usually a bit uptight, regimented and serious when in race mode.


At the other end of that scale is the reactive rider. Things are not necessarily certain or fixed and they don’t really care. They pay attention to the things that really matter but if something is not the same as it was yesterday it doesn’t upset their world. They just adapt or fix it somehow, or ride around it. When problems or changes come up in a race situation they react instinctively and the correct input just happens. Its more of a natural process and not a precise and deliberate decision. Their reflexes are usually very sharp and their inputs are strong. They know what they want and when they want it. In a car, the analytical rider is the one with his hands at 10 and 2 and his eyes and senses focused sharply. The reactive rider is the dog out the window, tongue hanging out and ears flapping, hoping something fun will happen.


Of course the aforementioned are two extremes and an infinite variety and combination of those types exist in between. But my point is this; I think that the second type, the reactive racer, is better suited to racing a classic sidecar.


Of course I have good reasons for stating that or otherwise I wouldn’t be writing this. It probably will not be a surprise to you that a P2 classic racing sidecar outfit is not a precise handler. It has a number of issues.


First, there’s the three wheel thing. The class rules state that the front wheel can be off line in relation to the back by as much as three inches – left or right is not specified. Next, there are no real definite parameters for where the third wheel is as long as the three form some type of triangle. It can be on the left (British style) or on the right (American style).


Second, the class rules state that the front and rear wheel must have suspension but the third wheel must not have suspension. In addition to that, chair wheel brakes are optional. You may have one if you wish, but nobody is going to make you.


Third, because of all its built-in idiosyncrasies, the whole outfit acts completely and radically different in a right hand corner than it does in a left.


So by now, if you know anything at all about handling and motorcycle dynamics, you are probably bent over vomiting. The combination is ludicrous. There is no way this horrifying aberration is going around the track at speed without putting up a massive fight. They wallow corner to corner after a big bump, they don’t lean into the corner, various wheels come off the ground without warning, they slide rather than steer – it's simply madness! This doesn't make any sense!


So I think you start to understand my judgement about the reactive style racer as being a better fit as a driver. It would drive the analytical driver to the edge of insanity. A well set up bike will go around the corner exactly the same way every time if inputs are identical. A classic sidecar, well set up or not, will go around that same corner and misbehave differently every time.


The controls positions are usually the same as a bike, clutch, front brake, shifter and rear brake are all in the same location even though the riding position is a bit different. Driving in a straight line is even quite similar to a bike. It's entering the corners where things start to go a weird place. As soon as the driver lets off the throttle, the chair and passenger momentum will try to swing the machine to the opposite side. So, under deceleration, if the chair is on the left, the front end will pitch to the right. That’s great if you are going into a right hander because it initially helps the turn. In addition to that, the driver also steers hard into the turn (no counter steering tactics here) which also helps with braking. The front tire is now pushing in a different direction from where the outfit is heading and is carrying much of the weight so it is effectively slowing down the whole machine. So unless it’s a really tight corner – no brakes required.

OK, so now the front end is looked after. Well, not really, because the dynamics get a bit more complicated but one thing at a time. Time for a quick look at the rear.


As mentioned before, when the driver rolls off the throttle going into the right, the left hand chair still wants to push. The front wheel is pitched too far to the right and already sliding sideways. These two actions combined will break traction on the rear wheel. It's not necessarily something that you want to happen but ends up being the end result of the combination of inputs that makes it go around the corner. By now you've already guessed it – yes, the whole thing is sliding. The next item on the very busy corner agenda is controlling that slide. Too far sideways and the whole show goes off the track. Not only that, it robs a tremendous amount of power to keep the drive wheel spinning while sliding and there aren't any horses to spare. They are needed for driving straight down the track. Not enough sliding

sideways and the machine won’t turn and is going through the corner far too slowly. This requires a very discerning use of the throttle, effectively steering the back end without losing forward momentum.


I haven't even started to talk about the passengers role in all this. He or she is also contributing dynamics that radically affect the machine. Going down the straight, setting up for the corner, helping to break the back end loose going into the corner, weighting the back, weighting the front – these are all things the passenger does that are totally independent of the driver and over which the driver has no control. There is no time when the driver can say exactly what the passenger will do. There are certainly expectations and “normal procedure” but the driver has to be able to respond immediately and control the wildly changing conditions.


Getting through the corner and getting the outfit to drive going out of the corner requires a whole different series of actions and I could continue with lengthy details but I'll leave that for a future blog. A description of left hand turning dynamics alone will require a few pages.


OK, back to my point about the type of driver required. I've touched on only a few of the demands without mentioning that these demands are changing constantly. The responses need to be instinctive, instantaneous and without conscious thought. It needs to be totally involuntary like breathing or blinking. The action has to happen without the thought. If there is any hesitation for thought, it is already too late. Experience helps a lot and a team working together over a long period of time will help reduce the variables. Like anything else, you get to know the machine, the track and your team member. I'm not saying that an analytical driver can’t do it, but they will be forced to change their style to become competitive in a racing situation.


A good example of using front wheel turning/braking to change direction. No brakes applied and the rear is steering/sliding.

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