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Two-Up Riding
Two-Up Considerations
Let me first say that I make a lousy motorcycle passenger; admittedly critical of my own riding, I'm absolutely paranoid about entrusting my welfare to someone else on two wheels. That being said, there are times when you may want or even need (in an emergency situation, breakdown, ect) to put someone in the pillion seat. If you're going to do it, you'll need to know the dynamics of taking on a passenger, as well as how to "train" that person so that you both arrive at your destination safely and unfrazzled.
Understand two things: 1. My comments here are reserved for sport and naked style bikes; the dynamics for heavier touring and cruiser bikes are similar but not exactly the same, but there are enough differences for me to make this disclaimer.
2. The techniques I offer are what have worked for me; others may have different preferences; so be it.
A few months ago, there was a series of photos circulating (I think they were killboy photos) of a young couple negotiating a rather steeply banked tight turn at a considerable angle of bank, the passenger smiling and waving at the camera in her shorts, tennis shoes and tanktop; (at least they were both helmeted). As the series of photos progresses, you can see the front wheel begin to tuck under, (the passenger still waving back at the camera, blissfully unaware of her own impending doom); and then the final series of shots of a jumble of bare arms, legs and the bottom of the bike, sliiiiiding across the pavement.
Nightmare, pure and simple.
Modern day sportbikes are little more than yesterdays racebikes fitted with lights and a horn.They are engineered to within a gnat's patoot to be the most responsive, precise, demanding and light machines EVER SEEN. A host of a suspension adjustements are available in 2-5% increments with just the click of a knob or twirl of a screwdriver, and tiny adjustments can make huge differences in chassis response. Riders practise their knee dragging skills, experimenting with just at what angle should they hang there knee; experimenting to see if they should scooch forward against the tank another half-inch to get the best traction in that downhill left-hander.
Now against this backdrop of precision and performance, how many of you have seen our hero, Lance Squidly, powering down the interstate on the latest techno-marvel sportbike decked out in shorts, wifebeater and sandals; with a 120 lb honey also so appropriately dressed, hanging out over the back, arms behind her on the bikes tail. Hold that picture in your mind.
Let me preface the rest of this with the admonishment that if you have'nt come to terms with the fact that gear, as much of it and as good quality as you can afford is mandatory, then the rest of this is just pi$$in in the wind; and that anybody you invite on the back ALSO NEEDS GEAR. PERIOD. The only exception would be an emergency situation where you are transporting someone stranded.
Chassis dynamics.
If raising or lowering ride hight a half-inch, or increasing or decreasing preload 5-10 lbs can have a measurable effect on handling, IMAGINE what plunking a 120 sack of pototoes on the back of your bike would feel like!.
What happens.
When you add that passenger, a couple of things immediately happen....
A. Due to the limited space on a motorcycle, the location of the passenger is over OR BEHIND the rear axel; this compresses the rear suspension, increasing preload, decreasing both available suspension travel and reducing ground clearance. Grounding hard parts becomes a real concern.
B. Depending on the bike, the relative weight of rider and passenger and their positions on the bike, the front suspension may compress or EXTEND! You have moved a large weight (the passenger) out on or past the centerline of the rear axel, this weight can act as a lever to actually REMOVE weight from the from wheel! This is why the vast majority of sportbike sngle vehicle crashes are usually low side front wheel washouts...decreased traction from an unloaded front tire.
C. Due to the compression of the rear suspension and the unloading or at least lower relative compression of the front, you increase the front steering static rake and trail, slowing steering inputs during acceleration and nuetral throttle.
D. During braking, because of the placement and long "Lever arm" of the passenger (the location of the weight of the passenger relative to static Center of gravity) you will experience more nose dive, and even suspension bottoming of the fork...this REDUCTION of rake and trail during braking causes QUICKENING of the steering, just when you need it least!
E. The additional weight causes an INCREASE in panic braking distances, and a decrease in maximum acceleration, plus an increased tendancy to wheelie due to the rear weight bias.
From a strictly performance perspective, this all appears bad; but the passenger isn't (or shouldn't be) a static load; and can contribute to if not icreasing overall performance, then at least ameliorating some of the negative effects.
Training a passenger is very similar to traing the rider....gear up, take it slow, and explain things along the way. The worst thing you can do to a new passenger is to surprise them. It's not enough to say "put your feet here and hang on". Hang on to what? That vestigal "grab rail" BEHIND the passenger? Your jacket? The tank? What?
Being a passenger on a modern sportbike usually means you are placed behind and anywhere between 2-6 inches HIGHER than the rider....go look at the placement of your own bike's passenger pad. That placement accentuates all the bikes movements relative to the passenger, plus, they have no handlbars to hang on to.
What I Do.
When someone rides with me as a pasenger, we first do a cockpit familiarization, just like I do with a new rider. They need to know what does what, so that they can learn to read and anticipate what the bike is going to do. This decreases surprises, and increases passenger (and rider) comfort. I then SHOW them how to get on the bike, and where to place their feet, then I get on the bike, and have them get on behind me. All of this with the motor OFF SO THEY CAN HEAR EVERYTHING.
We then talk about hand placement (on my hips or around my waist) and the fact they can use their hands on the tank as bracing during braking. We talk about what NOT to do (lean back, lean upright during cornering) and we talk about what I might do that I don't want them to do (hang out a knee or slide a buttcheek to the inside of a turn). I talk about the absolute requirement that they keep their feet on the pegs AT ALL TIMES, EVEN AT A STOP. If I have a bike with a centerstand, I may demonstrate the do's and don'ts so they know what these things feels like.
I also talk about the technique of keeping the head level with the horizon to prevent disorientation and to quell the fear of leaning, and to look through the turn. (If a lot of this sounds like what you learned in MSF rider class, it's because it IS).
We then go for a short familiarization ride, preferably in an empty parking lot, just for me to get a feel for what having a passenger is like, and for them to get a feel for the sounds and motion of the bike. THIS IS A LIKELY TIME YOU MAY DUMP IT IF YOU ARE NOT ABSOLUTELY CAREFUL. The additional high weight at low speeds and stops increases your chances of overbalancing at a stop and putting you both on the ground, so PAY ATTENTION!
Now go do your riding in low traffix areas, gradually working up the pace to a relaxed one.
You're not Freddie Spencer, so keep the pace cool; otherwise you'll risk having your helmet slapped by that frightened passenger, and remember that you have less ground clearance, less performance, and less traction when you might need it, and ride accordingly.
Sportbike riding with a passenger can be a rewarding experience, or it can be terrifying for the rider and the passenger; it just depends on how you approach it. Treat your passenger with respect, and train them right and you can have mucho fun WITHIN THE CONFINES OF REDUCED PERFORMANCE. Just like riders, different passengers have different tolerences and skills for speed and performance. A skilled and willing passenger can change your whole perception of riding two-up, increasing everybodies fun. Dragging someone unskilled and afraid into high-speed situations is not funny, and can be deadly.
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