Under Seat Steering versus Above Seat Steering
by Andreas Stiasny
When deciding for a specific recumbent bike model you will also have to decide
between under seat steering (USS) and above seat steering (ASS), also referred to
as over seat steering (OSS). Both have their advantages and disadvantages and it
is to a high degree just a matter of taste which one you prefer.
We will look at a few important points and compare how both steering
- Getting used to it
- For beginners it is easier to ride a bike with above seat steering because
they are used to have a handle bar in front of them on a conventional bicycle.
Under seat steering needs a little bit more time to get used to it. But after
some time of riding it should not be a problem at all.
- Shift Levers
- On a recumbent bike you usually have fewer options to choose your shift levers
than on a conventional bicycle depending on the angle between the ends of the
handle bar and your hands. For under seat steering the best fitting shift levers
are bar end shifters. Twist grip shifters are possible but because of
the reversed bar end you have to shift with your pinky and ring finger and not with
your index and middle finger. Rapid fire levers are usually not usable. With above
seat steering you have almost all options. Rapid fire levers may work depending on
the angle of the handle bar ends. Twist grip shifters and bar end shifters work fine.
- Brake Levers
- Brake levers should not be a problem. Only combined brake and shift levers should
be avoided on most recumbents (especially when using under seat steering).
- Rear View Mirror
- You should not ride a recumbent without a mirror because it is difficult to turn
around to look behind. Mirrors are often mounted at the bar end. This kind of mirror
can not be combined with bar end shifters. Therefore it may be more complicated to
fit a mirror to a bike with under seat steering.
- Speedometer, handlebar bag
- You may want to use a few other things on your recumbent bike that are usually mounted
on the handle bar. With above seat steering this is no problem. You can fit
a speedometer, battery lights and even a small bag to the handle bar.
When using under seat steering this is not possible or at least not useful.
You could fit a speedometer at the handle bar but you would not be able to see it
while riding. You have to attach it at a different place on the bike.
- A recumbent bicycle with above seat steering has better aerodynamics than a bike
with under seat steering. This is because when using under seat steering your arms
are in the air stream in their full length while with above seat steering your arms
are stretched to the front and causing a smaller frontal area.
- Leg clearance
- On a bike with above seat steering you have to take care to get enough leg clearance
when adjusting it to your leg length. You might have to raise the handle bar higher
than you need it for steering because otherwise you would touch it with your knees
when pedaling. Therefore bikes with above seat steering can be uncomfortable for
people with very long legs.
- Ease of Steering
On the first ride the steering of most recumbents may feel a bit nervous. That is
because of the different angle of the steering rod and because of the small front wheel.
You may find bikes with above seat steering even more nervous but it depends on the
geometry of the frame. You will get used to it very fast. Bikes with under seat
steering sometimes have indirect steering. You may need a short time to get used to it
but as long as none of the bearings has slack it will be no problem.
- Slow Turns
- When riding through U turns at very low speed you can't lean into the turn.
Therefore you need a bigger steering angle. But the steering angle may be limited.
On bikes with under seat steering the bar ends can touch the seat or your legs at
maximum steering angle. With above seat steering you may not be able to pedal at
maximum steering angle because the bar ends limit your leg clearance. This will
not be a problem when you are used to ride your bike but may be a concern for
beginners especially when riding uphill.
- Recumbents can be considered safer than conventional bikes with the possible
exception of visibility. If you hit anything you are more likely to hit it with your
feet than with your head. There is some difference between USS and ASS. In case of an
accident it is easier to get off your bike with under seat steering. With above seat
steering you always have the steering rod between your legs.
- Most people find under seat steering to be more comfortable especially for long
rides. Some people have reported numb hands or fingers when using above seat steering.
It's up to you to decide between above seat and under seat steering. Take what you
prefer. There is no technical reason to use one and avoid the other. As a tendency
you might prefer above seat steering for racing and fast touring and under seat
steering for relaxed touring and recreational riding. But in the end it's more a matter