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The Trike Fits the Rider - Not the other way around !

Imagine buying a $200 suit from the "One Size Fits All" rack. Think it will fit? You might get lucky, but not a likely outcome. OK so what if you were buying a $1000 suit; you would expect it to tailored right? Chances are the trike that's right for you is at least that expensive. Tailor it to fit YOU!

If you find that after an hour or two of riding leaves any pain or unexpected fatigue chances are you don't have the Trike optimally fitted.

Rider Dimensions:

Each of the measurement attributes in bold type below are critical measurements that anyone considering a great fitting trike should measure and record on a piece of paper for their shopping/fitting process. If a rider is outside the factory specified dimensional range of any given model it doesn't mean the trike can't be fitted; it is likely possible that the rider can still be fitted correctly although it may take some modifications. The trouble is few bike shops really have a good handle on how to fit a rider to a trike; many of them don't even do a very good job fitting a rider to any of the bikes they sell.

Rider Height is probably the most universal dimension used by the manufacturers to identify if a given model can be fitted to the rider.

Rider Weight is important as most trikes have a factory specified weight limit. If a weight limit is say 200 lbs and a rider weighs 225 lbs its not like the trike will break on their first ride, its more like a frame member is more likely to bend when the rider hits a large bump; usually large enough that it would damage a tire or wheel anyway.

X-Seam is measured with the rider leaning against a a board about 24" tall spaced about 12" from the wall. X-Seam gives an idea of how long the boom needs to be with the rider seated. If the rider is measured sitting flat against the wall rather then inclined it may add up to an inch to the X-Seam measurement. Contrary to what you may have heard if you're an inch off on X-Seam it may not make much difference for those between 5'4" and 6'0" tall.

Back Length is critical as most seats are made for a narrow range of lengths. Typically shorter then about 20" may require a smaller seat or added padding as there may be discomfort in the lumbar region or the top crossbar may line up with the rider's neck. When Back Length is longer the roughly 26" the upper shoulders may come in contact with a crossbar. These numbers vary from one brand to another. Whether its a Mesh Seat or a Hardshell it is vital that the rider has a seat that fits them. Some adjustments can be made by adding padding.


Thigh Width will determine the width of the seat needed. If you're a little wider then the seat was designed for, don't fool yourself into thinking you'll shrink to fit it. Do that and chances are you won't ride enough to shrink.....Mesh Seats have a fixed span between the rails. If your butt is spilling over the sides of the rails its quite possible to wrap some padding around the rails and re-string the seat to fit. Conversely if you're narrow enough to fit between the rails with inches to spare you'll want to keep the seat mesh tight. Put the palms of your hands on your hips and with your fingers pointed forward, measure the distance between them. Then measure the width between the rail centers.



Knees are the most heavily loaded joints when riding a recumbent. Some people have well used knees that don't work as well as they used. Good news for those folks; recumbent riding is one of the best therapies for knees including those with osteo-arthritus. The key is to take care of them. Those with no knee problems should be able to bend them down to 91° with no repetitive use pains. If your knees are weaker 94°-98° may be your limit. The longest leg should not be fully straight forward; at least 2-3° is recommended. You don't necessarily need a protractor & lasers to figure this out although they do help.... What we're trying to identify here is the crank length that best fits your "kneeds". The distance between the feet show works out to roughly twice the ideal length of the Crank Arms that will be best for you. The shorter your X-Seam is, the shorter the Crank Arms should be. Further, the weaker your knees are, the shorter your Crank Arms should be.



Arms are your inputs to controls. Elbows need to be bent enough that the rider can steer without the feeling of reaching. Not just going straight but through a tight turn as well. There are times where the rider will push themselves back in the seats with their wrists.


Measurements Recap:

  • Height
  • Weight
  • X-Seam
  • Back Length
  • Thigh Width

Basic Adjustment Points:

Seats are the most important element of choosing the right trike and may come in different sizes & configurations depending on the model.

Mesh Seats are the most forgiving as they do a great job conforming to a rider's body and breathe the best. Typically Mesh seats come only in one size although a few OEM's are beginning to offer XL versions for wider hipped riders. The added compliance of a Mesh Seat may not work for everyone. It is the rider's option to add padding for custom support.

Hardshell Seats provide a rigid base of support and almost always have compliant padding added. Typically they come in large & small sizes. Most Hardshell Seats tend to have narrow seat pans which work well on a two wheeler but may not be Trike optimal. Custom fitting padding is easier and typically once a rider has custom fitted padding they are more comfortable then a Mesh Seat. There are breathable padding materials that rival the breathability of a Mesh Seat.

Seat Recline Angle may be adjustable or fixed depending on the model. Lower Seat Angles tend to lead to neck strain. Higher Seat Angles tend to aggravate "Recumbutt" and "Sliding Forward". The simple point here is if you choose a fixed angle seat, consider how it will feel to ride in that position for an hour or more.

Seat Pan Width is generally sized for those with a belt size up to 46". If you're larger then that you may want to consider an XL seat.

Back Height is generally sized for someone between 64" to 75" tall. Torso lengths may vary but for the average person the stock seats are usually in that height range.

Ride Height can affect the ease in which the rider mounts on the seat. Tadpole Sport Trikes may have seats as low as 6" while Delta Trikes may be as tall as 18". Some seats have Ride Height Adjustment built in.

Padding can be used to tweak regions of limited support, raise a seat as much as 1 inch and move a rider forward 1".

Neckrests prop the neck with increasing support as the angle of the seat is more reclined. Most are adjustable in fore/aft up/down positions.

Hand Grip Position affects the angle of the rider's wrist & elbow.

Under Seat Steering (USS) offers a natural feeling steering action as it uses the Biceps/Triceps muscle groups similar to the muscles used to steer a car. Most USS bars provide a clamp that allows fore/aft adjustment but that's somewhat limited by the angle of the wrist. Some OEM's offer taller Grip Bars to accommodate shorter arms.

Direct Steering is a lower cost system that also reduces weight while providing ultra fast steering input. Unlike USS it won't use the Biceps/Triceps much, instead relying on upper shoulder muscle groups. Some allow fore/aft adjustment.

Shifters also have an effect on Hand Grip position depending on the type & mounting. Bar End shifters allow the highest position on the Grip Bar and are probably the best for smaller hands. Twist-Grip Shifters (Twisties) are usually mounted upside-down on Trikes forcing the rider to "pinky-shift". When the Twisty is upside down it forces the Brake Lever further down so it may be out of reach of the index finger.

Crankset Arm Length isn't adjustable however Cranksets can be replaced with various lengths. On any given Crank Length a rider with short legs will bend their knees more then a rider with long legs. As we age we find repetitive knee bends beyond 90° can induce pain. X-Seam is a pretty reliable method to match the optimal crank length to a rider's needs if they have strong healthy knees. In the event the rider's knees are weakened from conditions such as osteo-arthritus subtract 2 inches from your X-Seam. The following table gives a an accurate sizing for about 98% of all riders.

Recommended Crankset Lengths
Strong Knee X-Seam
Weak Knee X-Seam
Crank Length
84 RPM
90 RPM
97 RPM
105 RPM
112 RPM

Keep in mind that shorter Crank Arms also translate to smaller diameter pedaling circles so your feet will spin faster using the same effort. Spinning faster requires lower gear ratios. If you upgrade to shorter cranks it is recommended to also change the front chainrings to smaller sizes. See the Gearmaster Chart to identify optimal chainring sizes.

Clipless Pedals have a clevis device that attaches the rider's shoes to the pedals. If you don't use Clipless Pedals its just a matter of time before you really wish you had. There are adjustments to center and align the clevises on the shoes to eliminate any "knee wobble" a potential source of pain.

Boom Length is set based on a Rider's leg length and preferred knee angles. Traditionally most shops will take an X-Seam measurement to get in the ballpark for a rider then set the Boom Length. Of course that doesn't work in all cases, as 2 out of 3 will continually refine the Boom Length until the find the sweet spot.

There are few shops who will take the extra time to work with a rider to get everything fitted and for good reason. That leaves it to the rider to figure out. Generally the shop will do their best to get the Boom Length close and maybe the Hand Grip Positions and send the rider on their way.

We'll give you a range of rider pain & fatigue symptoms and the solutions as they would be applied to both a fixed seat model like the Direct Steer Catrike Expedition, and an adjustable seat model with USS like an ICE or HPV.