An excerpt from this article in Village News:
We Got Left in the Dust
We couldn’t keep up with our group of tandem riders who average 17-20 miles per hour and go much faster than that when they start to sprint. So we spent the first four months riding alone and hating it. On every hill climb and on every stop, we could not increase our speed fast enough and the other couples would pull away from us. We needed extra help whenever we had to accelerate.
Even if we were willing to ride alone, we still had a problem. We are serious bicycle riders and understand training. We know that exercise prolongs lives and helps to prevent many diseases, and that the more intensely you exercise, the greater the benefits. We know that an intense workout requires us to become short of breath and burn our leg muscles. The tandem trike offered so much resistance to our pedaling that our legs would burn, but we could not spin the pedals fast enough to become short of breath. You need to train at your “lactate threshold” to be able to compete and to gain maximum health benefits. You can’t really become short of breath on a bicycle unless you spin your pedals at a fast pace.
Bicycle racers know that to go fast, they have to spin the pedals at a fast cadence. Most knowledgeable bicycle riders try to spin their pedals at a cadence of more than 70 revolutions per minute, and most racers try to keep their cadence above 90 revolutions per minute. I tried lowering the gear ratio, to reduce the resistance of the pedals so we could keep up our cadence, but that caused us to have such low pedal resistance that we would spin the pedals so fast that the bike would travel even slower and prevent us from getting a decent workout. On hills, we would drop our gears as low as we could to raise our cadence over 70, and we would slow down to 4-5 miles per hour, which was incredibly painful to our minds as well as our bodies.
Electric Motor to the Rescue
Larry Black got us an electric motor from Falco Motors. They make motors that fit onto the hub of the wheel and can be put into any size of bicycle wheel. This motor has solved our problems and we are delighted with it.
• We can keep up with our group
• We get great workouts because we are the primary driving force on the pedals
• We can stop or slow down safely and know we will be able to catch up
• Carrying two batteries, we can go on 70-mile rides
Diana rides in the front (captain’s seat) and controls the steering and brakes, while I sit in the rear (stoker’s seat) and control the shifting and the motor. On a tandem trike, the strongest person should sit in the back seat because the person with the strongest legs generates the most power, and the back pedals connect directly to the drive chain. The rider in front loses a lot of power from the very long timing chain that runs from the front pedals back to the rear pedals. I turn the motor on by twisting the throttle on my handlebar. We use the motor assist only when we have to accelerate when we:
• start up after stopping,
• climb hills, or
• if other riders start to pull away from us.
The rest of the time I keep the motor off.
We start off with a short push from the motor. Then I adjust the gears to achieve a cadence of about 90 pedal rotations per minute. I do all our gearing by following the resistance on the pedals. If the resistance increases, I immediately lower the gear and do not wait for the cadence to slow down. I try to keep the pedal cadence at about 90 by adjusting the gears to the resistance of the pedals. When we start to spin much over 100 pedal revolutions per minute, I increase the gear resistance. When the pressure on the pedals increases significantly and I realize that a change in gearing will not keep up the 90 cadence, I turn on the motor and it makes the wheel spin faster so the cadence does not slow down.
How the Motor Gives Us a Better Workout
By not having to slow down when the pressure on the pedals increases, we are able to keep a fairly constant 90 cadence. This puts us at our “lactate threshold,” the ideal training level. When we are barely getting enough oxygen to meet our energy needs, we are exercising at the maximum capacity that we can maintain and still not have to slow down or stop. If we didn’t have a motor, our pedals would slow down so much that we would not gain the maximum training effect.