an open-ended unicycle rating system for describing the difficulty of riding obstacles in trials competitions, recreational trials riding, or very short technical sections of trail when mountain unicycling.

Based on difficulty grading systems for bouldering, the U-system is NOT the same as the International Unicycling Federation (IUF) Artistic Skill Levels. It DOES NOT consider riding technique and is not a skills progression in itself; a rider does not "achieve" a particular U-level by riding a certain set of obstacles. The U-system is a way to communicate technical riding difficulty.

The U-system rates the difficulty of the obstacle itself, irrespective of the technique used to ride it. Since it is impossible to describe every obstacle that a rider may encounter, the U-system describes basic reference obstacles that most riders should gain from experience. By learning to feel the difficulty required to successfully ride these reference obstacles, the rider should understand the effort required to succeed at a particular level. This allows and unlimited number of problems to be graded for difficulty without having to describe each one. As an example, an obstacle might feel like a U3 in difficulty, compared to other established U3 obstacles the rider has done.

The reference obstacles are intended to feel equally challenging, on average, for a well-rounded rider. However, like rock climbing, individual riders typically have particular strengths and weaknesses. For example, a particular rider might find hopping easier than balance lines at a certain grade, if they were better at hopping than at balance lines. It is important to emphasize that harder grades DO NOT necessarily mean bigger moves - a 1/2 meter gap to a difficult surface might be harder than a 2 meter gap to easy terrain.

The U-system is open ended and will change over time - harder and harder ratings are possible as the sport evolves. Join the discussion today

Below you will find descriptions of the reference obstacles for each level. By necessity, each obstacle is the simplest possible to describe. Despite the fact that the U-system rates obstacle difficulty, NOT the difficulty of moves, example techniques are provided to help give the rider a sense for the difficulty of these moves at different levels.


Moderately easy terrain encountered during cross-country mountain unicycling that is possible to ride purely by rolling.


Hopping up or down a set of basic urban stairs.
Riding along the edge of concrete street curbs bordered by grass.


Dropping from a bench seat to flat ground.
Hopping up 2 stairs in one jump.
Hopping through a rooty section of gentle trail.
Riding along flat-topped parking lot dividers.
Riding along a level 10 cm beam.
Hopping over car tire.


Hopping over a picnic table via the seats.
Hopping from the front hood of a junk car onto the roof.
Riding along a level 2 m long 10 cm beam.
40 - 50cm sidehop.
Pedal grab up to top of picnic table.
Riding along a railroad track for ~10 m.


Going directly to the top of a picnic table from the ground.
Riding along a 4 cm wide beam.


Dropping 50cm onto 10cm wide beam and ride.
Pedal grab onto 50 cm high, 10 cm wide beam and ride.
Riding over "average" junk car supported on blocks.


Scaling a technical 1 - 2 m boulder.
Sidehop to rubber on the back railing of a park bench-style chair, then ride.
Gapping horizontally across to a round railing 1 m away, then to the ground.
Pedal grabbing a fence, and then over the fence to the ground on the other side.
80cm sidehop.
Doing a 180° turn on a railroad track.


Pedal grab, and then go to rubber and ride 5 m on a 3 cm wide square railing.
2 m straight drop.
1 m sidehop.
1.5 m horizontal static gap.
Mounting and then ride along a 3 cm round horizontal railling for 5 m.
60cm sidehop to rubber on a 3 cm wide square railing, then ride 5 m.
Multiple gaps perpendicular to four 3 cm wide railings spaced 1m apart.
Ride along a railroad track, gap to the other track, and keep riding.


70 cm hop to rubber, then ride along a 3 cm wide round railing.
Gapping horizontally across to a round railing 1 m away, then to a another railing, then to the ground.
120cm sidehop.
Riding uphill or around curves on 3 cm wide round railings.
Multiple hops across 3 or more well-spaced round railings.
Pedal grab a 3 cm wide round railling, then go to rubber and ride.
90 cm high pedal grab, then to rubber, on a 10 cm diameter vertical pole.


Dropping 1 m onto 3 cm square railling and ride.
3 m straight drop.
Mounting on and ride a slackline or loose rope.
130 cm sidehop.
150 cm pedal grab height.


Jumping 1m from one horizontal railing to another, then sidehop up off of railing to another higher railing (round) and ride.
Greater than 3m straight drop.
Dropping 1m onto round 3cm round railing and ride.
Jumping onto a slackline or loose rope and ride.
140+ cm sidehop.
160+ cm pedal grab height.

180° Technique 180° lateral rotation of the wheel.
Beam Reference Obstacle A long, sturdy piece of squared timber or metal span varying in width in length. (~10cm width)
Clean(ing) Riding from the start to the finish of a defined section of trail or trials obstacle without falling or touching the ground with one's body.
Concrete Parking Space Divider Reference Obstacle Urban obstacle found in parking lots.
Course (Trials) A collection of individual trials sections.
Curb Reference Obstacle A stone or concrete edging to a street or path.
Dab To place your foot, hand, or other body part on the ground to maintain balance.
Drop Jumping from a higher to a lower point. Drops can be initiated from a static (stationary) stance or from rolling, with the saddle either between the rider's legs or held out in front.
Flow Complete mental engagement in an activity.
Gap Jumping from one point to another, where most of the travel is horizontal.
Going To Rubber Moving up from a pedal grab to riding.
Hop Technique A move by jumping.
Line A particular route through a section of terrain
Mountain Unicycling (Muni) Any type off-road riding on similar terrain to mountain bikes (including cross-country, freeride/dh or all mountain).
Obstacle A thing that hinders or hurdles progress presenting a unique challenge to a unicyclist.
Pecking Multiple static hops through a rough section of trail. This term is named after the mountain unicycling pioneer George Peck.
Pedal Grab Technique Jump into hooking a pedal on an obstacle, and moving from that position to riding on the obstacle.
Picnic Table Reference Obstacle A picnic table (or sometimes a picnic bench) is a modified table with attached benches, designed for eating a meal outdoors (picnicking) or trials riding.
Pre-hop Technique Intermediate, second hop when hopping onto an obstacle, used to increase hopping height.
Railroad Track Reference Obstacle
Section An obstacle, or series of obstacles, with a defined start and finish, that forms one component of a course in a trials competition. Also refers to a short segment of a trail.
Sessioning Process of practicing a line multiple times to achieve success.
Sidehop Technique Lateral hop. Typically used to gap horizontally (e.g. gap). Often done with seat out in front.
Stillstand Technique Balancing in place without moving.
Trials Unicycling involves riding over obstacles of any sort, either in natural terrain or in an urban environment, where the challenge is purely a function of technical difficulty over short distances. Riding techniques are employed purely as a means to negotiate obstacles.
UPD Unplanned Dismount (e.g. falling off).
U-system An open-ended unicycle rating system for describing the difficulty of riding obstacles in trials competitions, recreational trials riding, or very short technical sections of trail when mountain unicycling developed by Kris Holm.

2012 IUF Rulebook


Overview of Competitive Unicycle Trials

Extracted from The Essential Guide to Muni & Trials Unicycling by Kris Holm
The_Essential_Guide_To_Muni_and_Trials_Competition_Sidebar.pdf [164KB]

Difficulty Rating Systems: The U-System

Extracted from The Essential Guide to Muni & Trials Unicycling by Kris Holm
The_Essential_Guide_To_Muni_and_Trials_U-System_Sidebar.pdf [119KB]