HOW WE BUILT THE ULTIMATE MACHINEFOR INDOOR GROUP CYCLING

More than 20 years ago, Keiser set out to create a bikethat would exceed the demands of indoor group cycling.
•A bike that fits riders of all body shapes and sizes•

A bike that achieves a quiet — but true — roadbike experience inside your gym or homeThanks to the lessons learned from ourpast generations of bikes and our constantinnovations, the Keiser M3i isn’t just anyindoor group cycling bike.

•The ONLY bike built in the United Statesto ensure the tightest quality control

It’s the industry’s only indoor group cycling
bike built around YOU. That’s…
YOU the rider...and we accomplished it all withTHE SIMPLEST OFENGINEERING DESIGNS.

YOU the gym owner
YOU the service technician

HERE’S HOW WE DID IT.
SPECIFICATIONSHEIGHT45” / 1143 mm

LENGTH49” / 1245 mm

WIDTH
26” / 660 mm

WEIGHT
85 lbs / 38.6 kg

V-SHAPE FRAME(2.2m)

MATCHES RIDERS

OF ALL SIZES
Many indoor group cycling bike manufacturers
talk about providing a road-bike experience, butthey failed to recognize what’s important aboutroad bikes:

FRAMES VARY TO ACCOMMODATERIDERS OF DIFFERENT SIZES.
Our solution was to engineer the industry’s
FIRST V-shape frame for an indoor bike.

Our V-shape frame design allows the M3i to mimic
different road-bike frames by allowing the seat andhandlebars to be simply raised in conjunction with one
another to adjust for longer legs, torsos and arms.

The M3i matches riders from 4’10” to 7’ (1,473mm to2,233mm) tall with a weight capacity of 350 pounds (159kg).

FIRST TO ENGINEER A V-SHAPE FRAME

REAR-WHEEL DESIGN

Further protection of drive-train
The angled channel on the bike frame flows
excess fluid away from the drive-train.

Other indoor group cycling bikes mistakenly place
the rider’s sweat zone directly over the flywheel
and other vulnerable mechanisms — an obvious
engineering flaw that leads to corrosion, excessive
cleaning and a shorter bike life.
Keiser was the FIRST to put the flywheel at therear of a bike, allowing the M3i to be more reliable,easier to clean and better protected from sweat
and corrosion.

Less maintenance, longer bike life
With superior sweat protection, gym
owners can save money through lower
maintenance costs and a longer bike life.

FIRST TO ENGINEER A REAR-WHEEL DESIGN

MAGNETIC RESISTANCE

TRUE POWER READINGS
It’s easy to “claim” accuracy, but we guarantee it.
As the FIRST company to use magnetic resistance,
Keiser revolutionized indoor cycling by delivering aquiet, reliable ride with immediate accurate data for
EVERY M3i bike.
And unlike most competitors’ bikes, theM3i has been certified for accuracy.

The M3i is the FIRST indoor bike to receive theglobally recognized EN957-10 certification foraccuracy and safety.

IMMEDIATE RIDE DATAThe FIRST indoor bike designed to predict the power
generated at any speed in any gear — ensuring thatboth instructors and riders are provided withaccurate ride data immediately.

GUARANTEED CONSISTENCY
Our relentless Quality Control procedures ensure that every
M3i delivers the same immediate accurate ride data, bikeafter bike after bike. And every day an M3i production bikeis randomly dyno-tested to ensure quality and accuracy.

On the M3i, indoor groupcyclists can always hit
their power and cadence
targets immediately.

The nerve center of the M3i
The simple, elegant axle assembly is the core piece responsible
for predicting and delivering accurate ride data, EVERY TIME —and EVERY COMPONENT is inspected to meet precise tolerances.

FIRST TO USE MAGNETIC RESISTANCE

EVERY
magnetEVERY
magnet yoke

EVERY
magnet support

EVERYelectrical component

EVERYaxle

DRIVE-TRAIN

THE FIRST DRIVE-TRAIN

SPECIFICALLYDESIGNEDFOR MAGNETIC RESISTANCE
The competition endorsed Keiser’s engineering byfollowing our lead on using magnetic resistance — butthey should have also copied our drive-train design.
Our simple drive-train, with just a single
Poly-V belt, produces the higher
speeds necessary for a lighter-weight
aluminum flywheel to provide the kinetic
energy and magnetic resistance to simulate
a good road-bike experience. Using an outdated
drive-train, designed for heavier flywheels, ourcompetitors must use a perimeter-weighted
flywheel to accomplish the same thing.
They even brag about their perimeter-weighted
flywheel, cog-belt drives or crank-arm-to-flywheel
ratios. But what they’re really telling you is…

THEY DESIGNEDTHEIR BIKE WRONG.

FIRST DRIVE-TRAIN TO USE A POLY-V BELT FOR MAGNETIC RESISTANCEQUIET, SMOOTH AND
MAINTENANCE-FREE
To design their indoor bikes right, our competitors will haveto copy Keiser’s single Poly-V belt drive-train, because it’s theperfect balance between SIMPLICITY and PERFORMANCE.
The Poly-V belt is the key to our drive-train design because ittransmits very high loads over very small pulleys, achieving agood road-bike experience:•Without a perimeter-weighted flywheel•

Without a more complicated drive-train•

Without the unnecessary noise and vibration of a cog belt

No required maintenance, zero adjustments
The belt’s pre-tension design also requires zero adjustments,
and the M3i drive-train requires no maintenance other thanroutine inspection.

The Poly-V belt is THE choice ofautomotive manufacturers
The Poly-V belt
is the preferredchoice to run theaccessories on thefront of car engines,
because it’s soquiet, durable,
and reliable.

Q FACTOR & PEDALSCURVED CRANK ARMSTO FIT WIDER HIPSAND BULKY SHOES
Instead of using straight crank arms to achievea narrow Q Factor, Keiser recognized the needfor versatility. We added curvature to the M3i
crank arms to maintain the proper distance forwider hips and any type of rider footwear, fromnarrow bike shoes to the bulkier gym shoes
most commonly worn in group classes.

Many indoor group cycling bike manufacturers talkabout the distance between their bike’s two pedals,
and boast about their narrow Q Factor. But their bikes
were built around the narrow shoes and pelvisesof elite cyclists, even though footwear of any widthand people of all body shapes can be found in groupcycling classes.

WHY WOULDN’T YOU
DESIGN A BIKE TO FITEVERYONE?
The straight crankarms on mostindoor bikes are
only designed forbike shoes andnarrow pelvises.

Curved crank arms
provide ample room
for any type of rider
footwear, including
bulky gym shoes.

For SPD riders, thedesign of our bikepedal ensures thatthe cage below
remains parallelto the groundand clear of thefloor surface.

THE REVOLUTIONARYKEISER M SERIES PEDAL
Keiser also set a new industry standard with our SPDcompatible M Series indoor group cycling bike pedal.
Engineered beyond consumer standards for groupclasses, it’s more than a pedal — it’s a game changer,
providing superior comfort, safety and durability.

See how we reimagined our bike pedal at

KEISER.COM/PEDALTHE ONLY BIKE TO ACCOMMODATE ANY BODY SHAPE AND FOOTWEAR

Wide array of hand positions

THE DETAILSStandard media tray

Continuous design of handlebars
provides multiple hand positions
for indoor cycling.

For holding cell phones and tablets.

Easy access to shifter
Mounted directly to handlebars for ease of use
and increased safety, especially when riding outof the saddle. Interval training is activated bysimply pushing the shifter all the way down andback up, making it ideal for HIIT workouts.
The M3i features a wide array of details, benefits
and features, offering additional fit and comfort
for riders, enhanced durability for gym owners, andsimplified upkeep for maintenance technicians.

Simplified maintenanceM3i drive-train can beaccessed by removing
just eight Phillips
head screws vs.
over three times
more on somecompetitors’ bikes.

Water bottle holder
Incorporated into frame
design and fits both
small and large sizes.

Easy-to-adjust seatand handlebars
Quick, intuitive vertical andhorizontal adjustments ofseat and handlebars.

Robust knobs
Requiring less maintenancethan a traditional cam-lock.

Easy to transport
Fewer parts and a lighter
flywheel for ease of transport.

THE ONLY BIKE DESIGNED ENTIRELY AROUND YOU

Stretch pad
Located on bike baseto facilitate pre- andpost-ride stretching.

DIGITAL SYSTEM

KEISER DIGITAL SYSTEM

Track every ride
As the FIRST bike to offer Bluetooth® with open API, the M3i
is able to communicate with group class projection systems
while simultaneously syncing data to riders’ cycling appson their smart phones or tablets.

Record every detailTo meet the needs of riders, gym owners andmaintenance technicians, we thought of everything
when designing the Keiser digital system.

First computer toshow power output

Download the Keiser M Series or M Series
Pro app to easily log every detail of yourride and see your progress.

SUPERIOR TECHNOLOGYAND CONVENIENCE
Turn a class into a competition
The Keiser Projection System transforms
classes into interactive competitions byprojecting data onto a screen controlled by theinstructor. The system listens only to M Series
bikes via a triple-redundancy signal.

GET THE KEISER
M SERIES APPSThe M3i digital display issimple, with everything arider needs to know on asingle screen.

Back-lit display
Automatically turns onwhen the room lightdrops below a set level
and remains on,unlike otherbikes.

No buttons
Eliminating inconvenience anda cause of wear and maintenance.

FIRST WITH A STANDARD COMPUTER SHOWING POWER OUTPUT

Compatible with all major providers
As the industry’s FIRST company-designed projection system, Keiser
eliminates any need for gym owners to work with separate bike andprojection suppliers. But in true Keiser fashion, the M3i receiver isalso compatible with all major projection system providers, givinggym owners a wide array of options.

KEISER EDUCATIONTAKE YOUR CLASSESTO THE NEXT LEVEL
Become an instructor who teaches group classworkouts the right way thanks to researchbased educational courses from Keiser MasterTrainers proven to:•••

M3/M3i

In person — and online at keiser.com/education —Keiser’s world-renowned Master Trainers offer thelessons, skills and tools so instructors can take theirindoor group cycling classes to the next level.

FOUNDATIONS

Increase class retention
Improve client results
Boost the bottom line for your business

TECHNOLOGYMAGNETIC RESISTANCEENERGY SYSTEMSFoundations is an on-site, eight-hour course
during which a Keiser Master Trainer teaches andapplies all of the required information attendees
need to become a Keiser indoor group cycling classinstructor. The class includes:

Having a base understanding of the body’s energy systems is important for selecting the best type of drills
and training for a cycling workout. Prior to the contraction or shortening of a muscle, adenosine tri-phosphate(ATP), which is stored or synthesized in muscle cells, is broken down so energy can be released. ATP is
immediately available to the muscles and contributes to the three main energy systems called the ATP-CP,
Anaerobic Lactic Acid and the Aerobic Systems. The contribution to ATP synthesis varies depending on theduration and intensity of an activity being performed. For example, short intense exercise uses the ATP-CP
system for energy and longer duration activities rely on the Aerobic System.

keiser.com/education | 800.888.7009
M5i• It provides immediate feedback by displaying various metrics• The feedback can help engage and motivate the rider• It helps track a rider’s ongoing changes and improvements from workout to workout

M3i

STRIDERTOTAL BODY
TRAINER

M7i

WHEELCHAIR ACCESSIBLE
TOTAL BODY TRAINER

M3i

INDOOR BIKEEDDY CURRENT RESISTANCE
POWER = FORCEX VELOCITY(RPM)
An eddy current is an electric current in a conducting material that results from induction by a moving(measured in Watts)(gear resistance)• Can be initiated instantaneously

or varying magnetic field. In the M Series, the eddy current is generated by the flywheel passing throughtwo opposing magnets. The flywheel (a conductor) passes through the magnetic field generated by thetwo powerful magnets located in the magnet housing. By increasing or decreasing gears, the rider is varying
how much of the magnetic field comes into contact with the flywheel, thus increasing or decreasing the(60-110)(Power)(1-24)
amount of resistance accordingly. The magnetic resistance also allows the cyclist to enjoy a smoother,quieter and more predictable training session.
Power is the amount of work being done, measured in Watts, by the cyclist in a given amount of time.

• Depleted within approximately 10 to 20 seconds• Force is the amount of resistance from gear 1 to 24

1. ATP-CP• Used during maximal exercise intensity >90% max HR• Limited supply in the muscles

WATTS = GEARS X RPM• Power, speed and force are related. Power measures work intensity and it is modified by the twovariables of force and speed (distance/time)• Used during high intensity exercise >80% max HR• No oxygen is required so it can be initiated quickly• Depleted within 60 to 180 seconds• Lactate by-product of the lactic acid system changes the pH in the muscle, causing fatigue• It can create a better workout overall• It is an important teaching tool to assist the instructor
By cycling within safe cadence parameters, increasing the amount of power generated, observing net
calories expended and recognizing heart-rate variability, riders will benefit from a better and more
effective workout.
When riders have a strong understanding of the components of a proper workout, they are better equipped
to fine-tune their session. The motivation of the computer display is an important element in class design.
When used correctly by the instructor, this data provides helpful information by engaging and challenging
riders in each workout.

THE M3 & M3i
Before getting started, a rider should identify which Keiser M Series indoor bike model they are riding.
Although many of the features are the same, there are some slight differences.

• Velocity is speed, indicated by the cadence (RPM) at which the rider is pedaling

2. ANAEROBIC LACTIC ACID SYSTEM

A. Flywheel
B. Rotating Magnet Housing

To maximize power output, riders must regulate gear and RPM. While pedaling fast may appear
challenging, without any resistance the power output is low. In contrast, pedaling very slowly with highgears may also provide a less than desirable Watt output. Therefore, to maximize power output, manipulationof gear and RPM must be considered. In terms of effort, both components of power must be factored in.

Our calendar for upcoming Keiser indoor group cycling courses andworkshops can be found at keiser.com/education/training.

KINETIC ENERGY• Oxygen is required to produce ATP in order to sustain muscle contraction during
long duration and endurance exercises

Practical and theoretical training
A detailed training manual
A certificate of completion
Continuing Education Credits (CECs)

Energy Source

Anaerobic Lactic AcidAerobic

ATP is produced inabsence of O2 (oxygen)

Highly effective energy
production using O2 (oxygen)

Power Output
Activation SpeedTimeHighMedium

Low

Immediate

FastSlow

10–20 seconds

1–3 minutes

2 hours+

CP & ATP

Carbohydrates

Fats & Proteins

Peak Power

1 sec

20 sec

2–3 min

Maintain Peak Power

10 sec30 sec3 min

Fuel Source

1–2 min2+ hours

Full Recovery

3 min

1–2 hours

24–48 hours

Half Recovery

20–30 sec

15–20 min

5–6 hours

Capacity

The Foundations Correspondence option is offeredfor those unable to attend an on-site course.

SUPERIOR TIPS, TOOLS AND TRAINING

ATP-CPStored within the muscle

6–30 sec-28-

Strength–SpeedFORCE••••

Maximal Strength• Activities lasting longer than 3 minutes

In physics, the kinetic energy of an object is the energy that is created due to its motion. Kinetic energy
is defined as the work needed to accelerate a given mass from rest to its current velocity. Upon equalizing
this energy during its acceleration, the body of mass maintains this energy unless its speed changes.
The formula for kinetic energy is mass multiplied by velocity2, divided by 2. The standard unit measurementof kinetic energy is the joule.

KINETIC ENERGY = (MASS X VELOCITY2) / 2

Power

REGISTER FOR TRAINING
AT A GYM NEAR YOU

C. Cutaway Revealing Magnet

3. AEROBIC SYSTEM• Used during lower intensity exercise <80% max HR

Find additional
educational content at
youtube.com/keiserfitness

The M Series computer is a powerful teaching and programming tool because:

2470 S Cherry Ave | Fresno CA 93706 USA | education@keiser.com
TRAINING
WITH POWER
The power formula applied to indoor cycling is as follows:

KINETIC ENERGY APPLICATIONThe kinetic energy formula illustrates the importance of maintaining a minimum speed to ensure consistent
resistance while riding. In the development of the M3, the mass of the flywheel was created to maintainthe perfect amount of kinetic energy to keep the flywheel moving above 60 RPM. As speed is increased
from 60 RPM, more kinetic energy is generated and more resistance is created. Therefore, riders should
ride above 60 RPM.

KEISER M SERIES COMPUTERPHYSIOLOGYPHYSIOLOGY

The “M” in M Series refers to the eddy current magnetic resistance used in all of the Keiser M Series products.

TECHNOLOGYBECOME A CERTIFIEDKEISER INSTRUCTORTECHNOLOGYKEISER INDOOR GROUP CYCLING CERTIFICATION MANUAL(measured in joules)

M3

M3i

Speed–StrengthSpeed

VELOCITY-29--8--9-

Learn more online at

KEISER.COM/EDUCATION

Keiser’s commitment to constant innovation
continues to lead the indoor cycling industry.
With more than a quarter million of our M Series soldworldwide and countless reviews placing it at the topof the industry, it’s easy to see why there is no indoor
group cycling bike on the planet more proven than theM3i — and the only bike built entirely around YOU.

— Amazon.com (120+ reviews)“Best indoor cycle overall.”— SmartMonkeyFitness.com“A beast when it comes to spin bikes.”— BodyGearGuide.com“The design and appeal of the Keiser
M3i is worth the cost alone.”— Top Fitness Magazine

WATCH THE VIDEO

and learn more online at keiser.com/M3i.

Facebook.com/KeiserFitness@KeiserFitness@KeiserFitness@KeiserFitness

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