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Safety, Convenience, and Speed
Introduction
Safety
One of the primary weaknesses of standard upright bicycles is that they are unstable, especially at low speeds, when streets are wet, on gravel, on poorly maintained roads, and during startup. Another problem is that the rider sits high above the ground - a simple fall can result in a severe head injury. A third problem is the tendency for bikes to throw riders head-first over the handlebars in severe stops.
Semi-Recumbent (reclining) bicycles that put the rider eye-to-eye with motorists solve some of the safety problems. They also bring the head closer to the ground than convention "diamond" bikes and they do not pull the rider over the handlebars in severe stops. Semi-Recumbent bikes allow the rider to easily and quickly put both legs on the ground for stability during stops. However, even semi-recumbent bikes are not stable during startup. A small flywheel could be attached to the bike frame to greatly increase stability during startups, low speeds, and going up hills.
Semi-Recumbent tricycles solve the safety problems of both upright standard bikes and recumbents. They provide stability at startup, over wet streets, on gravel, on poorly maintained roads, and at all speeds. They are the safest cycling option. The primary limitation of semi-recumbent tricycles is their added bulk during transport and on some bike paths.
The best type of brakes are disk, then drum, then "V," and last are traditional bike brakes. A hub motor-generator with regenerative breaking can also improve safety by allowing quicker startups, better speed going up hills, and bursts of speed to get out of the way of cars.
An additional safety feature that is not yet included on trikes is a roll bar to provide visibility over the rider's head and between cars. The roll bar should be equipped with front and rear lights or LEDs for even better safety. See Cycling Equipment for sources of cycles, motors, solar panels, and fairings.
Convenience
Perhaps the two most important elements of convenience for a recumbent are transportability (up stairs, into homes, into a car, etc.) and seat placment. Some recumbents fold, some are designed for quick disassembly for placement in a standard suitcase, and some do not disassemble easily for transport. Folding bikes and those that are designed to fit in a suitcase are marked with an (F) in the chart below.
Most trikes place the double wheels 30 or more inches apart to provide stability when going over 30 miles an hour down a hill or making high speed turns. However, the width makes them more difficult to carry up stairs or get through doorways. More important, the width can make them less practical on bike paths or when mingling with cars. Several designs, such as JustTWoBikes Raven and MR Components Ultra, have double wheels 24 inches apart. Trikes that are narrow (24" wide), and therefore easier to transport, are marked with an (N) on the chart below.
Many recumbents are designed for speed, so the seat is placed inches above the ground and/or the rider is placed at an incline of 40 degrees or flatter. Although this helps with aerodynamics, it makes entry, exit, and visibility to other drivers more difficult. A particular challenge to entry and exit of a cycle exists when the seat is low, the seat is very reclined, double wheels are in front, and the steering is under the seat. Over the seat steering (with a pivoting bar) can greatly improve ease of entry and exit when the double wheels are in front. Having double wheels in the rear can also improve entry and exit. In the chart below, seats with a high seat (at least a foot above the ground) and/or with less than a 40 degree recline are marked with an (H) for "high seat." (The Raven seat can be quickly adjusted from low and reclined for speed to high and more upright for city traffic.)
Comfort
Comfort is guided primarily by the seat design and placement of shocks or shock absorbing bars. Most recumbents include a shock absorbing bar on the back of the seat and on one or more wheels. Some place shock absorbing material on the bottom of the seat. A few place shock absorbers over the front or rear wheels. If a cycle has shock absorbers (more than the shock absorbing bars), the cycle is marked with an (S) on the chart below.
Speed
Power and speed are affected by a number of factors, such as gearing, aerodynamics, tire weight, overall weight, weight of the rider, size of wheels, and more. (More can be found about the relationships at Bicycle Analysis and Forces on a Bicycle Rider.
Gear inch range is a key consideration. Many recumbents have a gear inch range of around 20 to 100 gear inches. Generally, the greater the range (difference between lowest and highest number), the farther the bike will go with one pedal turn, especially as the lower number goes below 20. You can do your own analysis of how fast a bike or trike will go with different gear and wheel size combinations. For example, comparing the MR Components Swift Ultra (with Speed-Drive and 73 inch chainwheel) to the standard Kettwiesel (9 gears) can show most of the difference in speed. The Ultra with Speed-Drive has a gear inch range from 12 to 190 and the standard Kettwiesel has a gear inch range of 29 to 92. We can compare how fast the wheels would go while pedaling one turn per second on a level ground with no wind and while using the gears for most speed for each trike. The standard Kettwiesel can go up to 11 miles per hour, while the Ultra can go up to 56.5 miles per hour.
See the chart below for a standardized speed score (using gears alone to predict speed) for a sample of recumbent bikes and trikes. Some include a "Speed-Drive" option, which may substantially improve the distance traveled with one pedal turn (for about $350). A Rohloff Speedhub may also improve performance (for about $800), but the Rohloff Speedhub was not included in the samples below. (MR Components, Greenspeed, and others provide an option of having both the Speed-Drive and the Speedhub)
However, factors other than gears stongly affect the actual speed achieved by each cycle. It would be difficult to maintain a speed of over 20 mph without some kind of aerodynamic assistance, such as a windshield. Examples of other factors that would also influence speed include wind speed and direction, rate of incline, road surface, seat design and placement, quality of materials, tire weight, and frame flex.
Since aerodynamics of a cycle is important for speeds over 20 mph, coverings on a bike can improve speed substantially. A front fairing (windshield or nose cone) can reduce drag and improve speed by 20 percent or more by the time the rider exceeds 20 miles per hour. A rear fairing can reduce drag a great deal also, possibly another 20 percent. Coverings can also protect the rider from rain and cold.
A third important design feature that affects speed is the weight of the cycle, especially going up hills. The lower the weight, the faster a bike can go up a hill. Adding a windshield that weighs several pounds would still make sense, however, because the slower speed going up a hill would be more than made up going down the hill. A 30-pound aerodynamic bodyshell, however, may make going up hills impractical without a motor. Good recumbents weigh less than 35 pounds. Some recumbents have frames of titanium or carbon fiber to lower weight down to around 18 pounds--and cost accordingly.
A fourth ingredient for speed is stiffness of the frame; generally, the stiffer the frame, the more power goes to the wheels. Some recumbents build in some flexibility in the frame to make the bike ride more comfortable, however. In general, a good recumbent will have some method, such as shocks, to reduce the harshness of the ride.
Seat design affects speed. The seat needs to provide sufficient solidness to provide power, yet needs to be made of material that allows absorption of road bumps. The seat material should be porous and light. The seat should detach from the cycle easily and quickly for transport and storage. The seat should also adjust to different angles to fit the needs of different riders.
Some designs place the seat several inches above the ground and/or use a very reclining position for best aerodynamics. However, this may be too low for persons wanting to use the cycle for neighborhood errands. In the chart below we mark cycles with a seat bottom at least a foot above the ground and with less than 40 degrees of reclining with an (H) for "high seat."
Finally, and perhaps most important, a light weight electric motor and batteries could add greatly to the power of a bike or trike. A motor with light weight batteries and regenerative braking would be ideal. In order to keep the weight down to around 15 pounds, an electric motor and battery combination would be just powerful enough to supplement pedal power when going up hills or to provide a burst of speed when needed in traffic.
Standardized Speed Scores
A "standardized speed score" can be calculated by determining the maximum miles per hour possible on a cycle that is traveling on a level surface with no wind, with a pedal rate of one turn per second, and with its best gear combination for speed. (The score also assumes 20 inch wheels and does not consider wind drag, roll resistance of tires, weight of the cycles, frame flex, quality of materials, and other factors.)
In practice, speeds of over 25 mph cannot be maintained without strong aerodynamic assistance, a light weight cycle, light weight wheels and tires, stiff cycle frame, excellent conditioning of the rider, and other factors.
Cost
Recumbents range in price from around 500 dollars to over 5,000 dollars. Two thousand to three thousand dollars is a typical price range. Examples of some of the the better recumbents, in order of price, is provided under "Purchase Resources" in Recumbent Bicycles. Most of the examples are for models that cost less than 2,000 dollars. Likewise, prices for examples of tricycles are available under Tricycles
Evaluation
If you are going to purchase a cycle as your "neighborhood vehicle," you can compare several at a time using more detailed criteria on the Cycles Comparison Chart. The Chart can also be used as a basis for asking questions of dealers before making a purchase. Some bikes have upgrades available that are not listed on Websites. For example, some manufactureres will replace a standard 9-speed hub with a "Speed Drive" if the upgrade is requested. (Changing the hub, for example, could boost the top speed of a cycle by a third for $250-$300.) Some manufacturers, such as S & B Recumbents and Greenspeed, advertise that they customize their products for their customers.
Recommendations
If cost is your primary concern, then consider the EasyRiders EZ-1 (500 dollars), EZ-1 Lite (750 dollars). The EasyRiders have gotten better ratings for speed and ride quality, but more local dealers are available for BikeE. Having a local dealer may be important if this is your first recumbent.
If you want an alternative to a car for short trips, then try a good tricycle, such as some of those listed above, and consider adding Speed-Drive to increase speed. For even more speed and safety, add front and rear fairings (coverings), a hub motor with regenerative braking, a seat belt, and a roll bar with day running lights. For even more safety, wearing a motorcycle helmet may also be wise when riding a trike with a supplemental motor.
Trikes come in two basic designs. Trikes with two wheels in back are called a delta design (left) and trikes with two wheels in front are called a tadpole design (right). Tadpole trikes are typically designed for speed so they place the rider close to the ground for better aerodynamics and to help avoid tipping in fast turns.
The delta trike design with two wheels in back has other advantages. It should require fewer adjustments because the double wheels do not have be used for steering. In addition, these trikes are usually much easier to enter and exit because the seat is higher and the double wheels are not in the way of sitting down. If the seat is higher on the delta trike, it makes the rider more visible to drivers. Further, the delta trikes have usually been designed for hauling groceries and other large or heavy packages because of the larger space behind the seat and the greater weight carrying capacity of the double wheels in back. The delta trikes have usually been made much heavier than tadpole trikes (to haul more weight) and have gears that support power at slow speeds. They are rarely designed for speed.
A commuter trike should combine the best of each basic design. The seat should be able to go higher and more upright in traffic and then go lower and more reclined for going down steeper hills or away from traffic. The bike should be narrow (two feet wide or less) to allow safe use on bike paths and in traffic. The cycle should have gearing that will allow it to go 20 to 30mph (at one pedal turn per second) in traffic or for long stretches away from traffic. The cycle should have a seat high enough to allow the rider to repeatedly enter and exit comfortably and the wheels should not be an obstruction. The cycle should weigh less than 35 pounds (for hills) or should have a supplemental electric motor to help with hills.
A motor-generator can also provide a burst of speed when needed and allow the rider to stay up with some city traffic. An example of a hub motor system that includes regenerative braking is the Birkestrand. With regenerative braking, the hub motor-generator can charge the batteries whenever the brakes are applied or by pedaling while waiting at lights. (The system, including motor-generator, batteries, controller, and recharger, weighs around 15 pounds and costs around 500 dollars.) If a motor is added, it is best done at the time of purchase so that the trike manufacturer ensures proper fitting of components. Adding a motor-generator with regenerative braking to the trikes gives the design on the left an advantage for neighborhood commuting.
Front and rear coverings (fairings) can increase the aerodynamics of the trikes, which is important because 80 percent of the power (at 20 miles per hour) is used to overcome drag. The fairings can greatly improve the speed obtained with moderate pedaling. If fairings are planned, they are best applied as part of the purchase so that the manufacturer installs fittings for them in the correct places. A rear fairing that can double as a covered grocery bag carrier would be ideal. A bodystocking can provide aerodynamics, as well as protection from rain and cold, at the cost of convenience when entering and leaving the cycle. Custom coverings can also be constructed from kite material, such as fiberglass poles and ripstop nylon.
For long trips, camping, convenience, and environmental friendliness, solar panels ($700 for 100 watts, 24 volts) could be attached to the top of the rear fairing for quick (2-hour) charging of the battery pack or charging an additional battery pack. Alternatively, a light weight, flexible solar panel ($400 for 32 watts, 24 volts) could be fitted to the windshield to provide more of a trickle-charge. (Care must be taken to ensure that the controller for the solar panel fits the particular type of battery pack. In addition, batteries create heat when they are being used or charged, so they should not be in an enclosed space during those times or they could be damaged from overheating.)
A roll bar extending over the rider's head can provide visibility between cars and also house front and rear LED lights. For protection from rain, a removable, clear plastic cover could be fitted between the roll bar and the nose cone. The plastic could be coated with a rain repellent to maintain high visibility during rain without windshield wipers. The removable cover would also be desirable for longer trips to increase aerodynamics and reduce drag.
If the trike is going to be used for carrying heavy loads or large loads on a regular basis, a trailer should be considered, such as the CycleTote with automatic disk brakes. A trailer can make shopping or camping much more convenient.
To complete the concept trike, a hole could be placed in the nose cone and an electrostatic air filter could be located in the hole to reduce the pollution from autos. In the summer, water could be dripped over the filter to provide evaporative cooling.
Summary
So, which trike makes the best alternative for a car for short trips?
If cost is most important, consider the MR Components Swift ($900).
If convenience is most important, consider the JustTwoBikes Raven with Speed-Drive ($2,950). It is only 24" wide (for bike paths), can be disassembled easily (for transporting), has good cargo room in back, and is easy to enter and exit. It also has a front wheel drive for quietness and easy maintenance. A less expensive trike that has good carrying capacity and is easy to enter and exit is the Triumf with Speed-Drive ($1,750). If just the narrow width (for bike paths) is important, consider the MR Components Swift Ultra ($1,750). (The Ultra is also very light, good for climbing hills.)
If comfort is most important, try the Lepus ($2,500). It is one of the few recumbents with a rear suspension. The Lepus also has many convenience features, such as ease of entry, good cargo carrying capacity, and good transportability (it folds).
If safety in city traffic is most important, consider the JustTwoBikes Raven again. The narrow width may be important for competing with traffic or using a bike path safely. In addition, the adjustable seat should allow the rider to be upright enough to be visible to drivers. The trike includes disk brakes and the front end moves independently of the back two wheels for leaning into turns at higher speeds. If safety going down steep hills at high speed is most important, then the MR Components Swift Ultra would be a better choice because you will be so close to the ground. If a bike is preferred over a trike, then consider attaching a small flywheel to the bike frame to greatly increase stability during startups, low speeds, and going up hills.
If speed is most important, consider the MR Components Swift Ultra with Speed-Drive ($2,750). In addition to having a wide gear range, it is one of the lightest bikes--for more speed going up hills. It is also narrow and small for easier transporting than most trikes.
The most ideal trike for you depends on how you will use it. If you are going to use your cycle mostly in neighborhoods where you compete with cars or use bike paths, then the JustTwoBikes Raven makes sense because it is narrow and you can sit somewhat upright. If you are going to travel long distances with little traffic or with steep hills, then the Greenspeed, Ultra, or Swift make sense because of aerodynamics, low weight and high gears. If you want to be able to take your trike on a plane from time to time, then both the Raven and the Greenspeed can fit in a suitcase. If you will need to take your cycle up stairs each day, then weight and width are important. The Raven (width), Greenspeed (weight), or MR Components Ultra (width and weight) might do for stairs. If you need your cycle for carrying groceries or camping gear, then the Raven, Triumf, Titan, Penninger, Kettwiesel, or Lepus would work--or you could get a trailer for your cycle.
If you need your cycle partly for busy city driving and partly for long country stretches, then you might be wise to select one of the safest city options with narrow width and more upright position, such as the Raven. If you need it partly for long, flat stretches and partly for steep hills, then you might be wise to pick one of the lightest cycles with good aerodynamics, such as the MR Components Ultra. If you need your cycle for hilly city driving, then you need to select the lightest cycle and be sure to use a roll bar with lights for visibility. If you want to ride tandem some of the time and solo some of the time, then consider getting two Kettwiesels because they can be combined into one tandem bike and then quick released for solo.
If you are going to use an electric motor for supplemental power, which is highly recommended, then the ten pounds difference between trikes should not be a factor in climbing hills. If you are going to use a motor, then the Raven makes a good choice because it is easy to enter and exit, is narrow for city use, can allow upright posture in the city and aerodynamic posture in the country, can be disassembled easily for transport in a car or plane, can carry cargo, can be carried up stairs and through doorways, and has a reasonable gear range.
To summarize, an ideal trike has several important features. It should have a seat that can be positioned up and down, depending on whether speed or visibility is most important; seat angle should also be adjustable. The double wheels should be 24" wide to allow safe use of bike paths and to handle heavy traffic. It should fit in a standard car trunk. It should have a rear suspension for comfort. It should have a front wheel drive for quietness and easy maintenance. It should have a wide gear range, allowing it to keep up with neighborhood traffic when necessary. It should weigh less than 35 pounds for climbing hills. (Weight can sometimes be reduced inexpensively by using a lighter seat or tires.) It should be able to handle a couple of bags of groceries. It should be convenient to enter and exit. It should include fenders, rearview mirror, a chainguard (including leg protector), and mountings for lights, rollbar, seatbelt, front fairing, rear fairing or carrier, and water bottle. Last, and not least, an ideal trike that can be used for commuting should have a minimalist version available for under $1,000.
A recumbent trike handles differently from a standard upright bike and different recumbents handle differently from each other. "Try it before you buy it" is a wise step in the process. A test ride should help you decide if a recumbent trike with a supplemental motor is for you. Further, replacing parts and making adjustments may be difficult without a local dealer. (None of the four trikes discussed above has a national network of dealers in the USA.) To find recumbent bike and trike dealers in your area, try the list of dealers by People Movers. Perhaps a local recumbent trike dealer would be willing to handle service and repairs, even if the trike you select is not one of their brands.
Also Try
Recumbent Bicycles
Tricycling
Electric Cars
Pollution
Global Warming
Energy Efficiency
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