3 Wheel Recumbent Electric Bikes

© Brooke Clarke 2010 - 2019

Existing Pedal Power Bikes-Trikes
Electric Conversion
    Drive Method
Related Web Pages


I recently saw the iZIP three wheel bicycle.  I'ts got a small electric motor, two rear wheels and a basket for carrying stuff.  I'd like something similar except with more power to handle the hills between me and my mail box or better between me and downtown (less than 10 miles one way).

A wheel configuration where there are two front steering wheels and a single rear is what's called a stable configuration.  Two fixed front wheels and two rear steering rear wheels (a car driven in reverse) is an unstable configuration as is one front wheel with two rear fixed wheels.   (Wiki: Three-wheeled Car)

It would be a real bonus if the bike could pull a small trailer that could be used on the paths near my house to haul wood, carry supplies, etc.  So, what I'm after is more like a 3-wheel utility vehicle.

Existing Pedal Power Bikes

Tadpole Trike Design - Recumbent seating (Wiki: Recumbent bicycle), two front wheels with pedals out in front.  Single driven rear wheel.
Direct steering has the hand grips connected to the hub with a short solid tube.  The wheels are interconnected with a link that sets the toe in.
With direct steering when a Bionx electric controler is fitted to one of the hand grip bars it may hit you leg in a corner and change the setting.
Linkage steering has a handlebar with links to the two steering wheels.  Has Ackerman geometry (WikiRC Tek).


Max road rider wt.: not mentioned
Tadpole recumbents and a 2-wheel recumbent for speed

Electro Ride

6923124 (USPTO)  Tritrack system of mass transit, Roane; Jerry M. (Austin, TX), 104/124 ; 104/118; 105/141; 105/72.2
7127999 Tritrack system of mass transit, Jerry M. Roane
7334524 Production vehicle for tritrack transportation system, Jerry M. Roane


Very pricey.

Inspired Cycle Engineering (ICE)

Full Fat $10k


Retro e-bikes - battery holder looks like Harley V.
36 & 48 Volt versions.



8 1/2" seat height
43 pounds
X-seam: 35.5 to 44"
Max road rider wt.: 300 #\

Light Foot Cycles

Have experience with both Gas and Electric assist.
The delta configuration Road Runner can use either type of assist.
Lightfoot Road Runner delta trike

The above Road Runner is shown with the optional link steering.  The stock steering would be regular handlebars coming up from the front wheel.  The problem with the stock steering is that the handlebars will stick out rather far when making a sharp turn and would not fit into the Rain Shadow body.  That may be one of the factors leading to the development of the Express Trike.  The Express also has a higher bottom bracket so the bottom of the sprocket is above the floor.
Road Runner $ 3300 + $350 for 2-wheel drive, a little over $6k with mid drive electric motor.

Sun - J&B Importers

EZ-3 SX Tadpole

14" seat height
49 pounds
X-seam: 33 to 47"
The seat attaches to the frame in one of three possible positions.  The forward book can be adjusted in length, but that requires adding or removing chain links.
Owner's page

EZ-3 USX HD Trike

Sun EZ-3 US
              XHD Trike 68611
The bike has a MSRP of about $1000.

Sun Seeker Fat Tad

Electro Portal motor kit (w/o battery for the EZ-3 is about $ 600
ECO Speed Electric Mid Drive (EMD) motor kit is about $ 1000 to $ 1500 depending on the motor WILL NOT FIT US XHD because of the under seat steering linkage.  The hub motors are not suitable when driving in hilly country.

X3 AX Trike

Sun X3 AX 68609 Trike
Recomended by ECO Speed.  About $1700 retail.  The idler tab needs to be cut off the frame for the mid motor installation.
The tab that's holding the chain idler needs to be cut off in order to install the ECO Speed mid drive electric motor.


Max road rider wt.: 250 to 300 #

Trident Terrain Fat Trike

Two steering wheels in front, single fixed drive wheel.
Available with 750W Bafang motor (which one: 8fun mid drive)


Max road rider wt.: 252 #

Utah Trikes

Fat Tad Crawler
Differentials - UT Custom -
Electric Motorized UTCustom Catrike Fat Cat-4 Quad - Bafand 1kW motor,

Electric Conversion

Wiki: Motorized bicycle, motorized bicycle history, Electric bicycle laws:

The U.S. NHTSA Code of Motor Vehicle Safety simply defines low-speed electric bicycles as consumer products and not Motor Vehicles for safety standards. In doing so they vest authority over commercial safety standards to the Consumer Product Safety Commission.

The Consumer Product Safety Commission(CPSC) stipulates that commercially manufactured low-speed electric bicycles, or tricycles, must have fully operable pedals, an electric motor of less than 750W of power and a top motor-powered speed not in excess of 20 miles per hour (32 km/h). An electric bike remaining within these specifications will be regarded simply as a bicycle for purposes of safety standards. This supersedes any state law that is more stringent, but only regarding safety equipment required on electric bicycles and the standard of manufacture they must meet.. The legislation enacting this amendment to the CPSC is also known as HR 727.

CA 24016 Motorized Bicycle Electric Motor: Safety and Equipment Requirements -
CA VC 406 Motorized Bicycle -
406.  (a) A "motorized bicycle" or "moped" is any two-wheeled or three-wheeled device having fully operative pedals for propulsion by human power, or having no pedals if powered solely by electrical energy, and an automatic transmission and a motor which produces less than 2 gross brake horsepower and is capable of propelling the device at a maximum speed of not more than 30 miles per hour on level ground.

(b) A "motorized bicycle" is also a device that has fully operative pedals for propulsion by human power and has an electric motor that meets all of the following requirements:
(1) Has a power output of not more than 1,000 watts.
(2) Is incapable of propelling the device at a speed of more than 20 miles per hour on ground level.
(3) Is incapable of further increasing the speed of the device when human power is used to propel the motorized bicycle faster than 20 miles per hour.
(4) Every manufacturer of motorized bicycles, as defined in this subdivision, shall provide a disclosure to buyers that advises buyers that their existing insurance policies may not provide coverage for these bicycles and that they should contact their insurance company or insurance agent to determine if coverage is provided.

(c) The disclosure required under paragraph (4) of subdivision (b) shall meet both of the following requirements:
(1) The disclosure shall be printed in not less than 14-point boldface type on a single sheet of paper that contains no information other than the disclosure.
(2) The disclosure shall include the following language in capital letters:
Amended Sec. 1, Ch. 804, Stats. 1995. Effective January 1, 1996. Supersedes Sec. 2, Ch. 342.

CA CHP Motorcycles and Similar Vehicles - pdf version
Motorcycle - >= 150 cc displacement
motor-driven cycle - < 150 cc displacement
moped or motorized bicycle -
Section 406(a) VC refers to a moped or motorized bicycle as any two or three wheeled device having fully operative pedals for propulsion by human power, or having no pedals if powered solely by electrical energy, has an automatic transmission, and a motor which produces less than 2 gross brake horespower and is capable of propelling the device at a maximum speed of not more than 30 miles per hour on level ground.

Section 406(b) VC refers to a motorized bicycle as a device that has fully operative pedals for propulsion by human power and has an electric motor that:
  • Has a power output of not more than 1,000 watts;
  • Is incapable of propelling the device at a speed of more than 20 miles per hour on level ground; and
  • Is incapable of further increasing the speed of the device when human power is used to propel the motorized bicycle faster than 20 miles per hour.
It's not clear to me if you can have an electric motor powered bicycle (with pedals) and a 2 HP electric motor?  I think if it's got an automatic transmission then 2 HP (1492 Watts) is OK without the auto trans 1000 Watts shaft output is the limit, i.e. the electrical input will be higher than 1 kW).

IA problem with the motorcycle is that there is no provision for pedal power because the vehicle weight is much to high.  So for a vehicle to have a motor and pedal power it needs to be as light as possible.  That's especially important if climbing hills is involved and not so important on flat ground. See:
Electric Vehicles: Design and Build Your Own by Michael Hackleman, April 1977, ISBN: 0-915238-17-9 (Amazon.com)


A 2 HP electric motor in a vehicle weighing 125 pounds would be a target.  The Sun EZ-3 SX Tadpole might be a starting place.
Next, see if something like the Sick Bike Parts Jack Shaft Shifter Kit can be used to mount a motor so it drives the pedal crank or chain?
Look into a new vehicle that would use the Cloud Electric Package Electrathon CloudEV/Scott Upgrade 1.6+ HP Motor, Alltrax Programmable Controller and the Sick Bike Parts Jack Shaft Shifter Kit.  This would use tires that can hold more weight (400 # total curb weight).
A frame something like for patent 5263732 (below) except with battery mounting and maybe suspension if there's some weight available.

There are a number of considerations.

Drive Method

Most drive methods are not compatible with regenerative braking because of the freewheel that's needed to allow coasting without forcing the pedals to turn.
Also all the information I've been able to gather shows the efficiency to be considerable below 10%.  Not sure why that's the case.

Tire Friction Drive

Easy installation - very poor efficiency.  Does not work in snow, rain, sand or gravel
6065557 Power assist assembly for wheeled vehicles, Peter H. von Keyserling, May 23, 2000, 180/221; 180/651; 180/342; 180/907
dual motors on common shaft single friction wheel
5316101 Electric and pedal driven bicycle with solar charging, Henry M. Gannon, 180/221; 180/22; 180/220
3961678 Simple electric bicycle, Yukio Hirano, Akio Iwata, Jun 8 1976, 180/220 ; 180/205; 180/221; 180/343; 200/61.85 - single motor
627066 Automobile, J. Schnepf, Jun 13 1899, 180/220 ; 180/205; 180/221; 180/342; 244/103S; 310/75C; 476/64 -
electric motor friction drives rear wheel
3431994 Electric Drive for Bicycles, Garfield A. Wood Jr, Mar 11 1969, 180/220 ; 180/205; 180/221; 180/342; 180/65.6; 310/112; 310/152 -
electric motor friction drives front wheel
596273 Electrical Bicycle, Hosea W. Libbey, Dec 28 1897, 180/220 - electric motor between pedels
596274 Electrical Bicycle, Hosea W. Libbey, Dec 28 1897, 180/220 - motor sits above rear wheel and driver rear sprocket
627066 (see above)
2463349 Electric Motor Assembly, Rawlings R. Baner, Mar 1 1949, 310/112 ; 74/421A -
3 electric motors in a single housing drive a common reduction gear
2491076 Propulsion of Cycles, Mario Benazzoli, Dec 1949, 180/205 ; 180/221; 180/299; 180/342 -
engine is hung behind pedels and friction wheel drives rear wheel
928928 Motor Attachment for Bicycles, Gottleb Belz, Jul 27 1909, 180/221 ; 180/205 -
gas engine at center of frame drives friction roller on top of rear wheel
1410180 Motor Cycle, H. Hildebrand, Mar 21 1922, 180/205 -
gas engine in front of pedals drives large pulley attached to rear spokes (Wizzer)
2091698 Cycle Construction, W.C. Anthony, et al, Aug 31 1937, 180/228v - engine in front of pedals drives worm gear on pedal shaft
2274043 Motorized Bicycle, Leslie S. Cushman, Feb 24 1942, 180/221 ; 180/205 - engine hung at rear friction drives rear wheel
2920845 Airplane Moving Device, D.A. Palmiter, Jan 12 1960 - geared down electric motor drives friction wheel on plane wheel
3075599 Aircraft Tug, Yadon et al., Jan 29 1963, - 2 wheels and a belt make for more contact area between the friction drive and wheel
3361917 Permanent Magnet Motor, D. C. Stahly, Jan 2 1968, -

Drive Through Pedal Shaft

Uses gear box and allows existing gearing to be used for hill climbing.  Heavy.  Down gearing in front of pedal shaft then up gearing is inefficient.
596272 Electrical Bicycle, Hosea W. Libbey, Dec 28 1897, 310/66 ; 310/268 - electric motor between pedels
6230586 Electric drive device for a bicycle, Chung-Hsi Chang, 74/625 ; 180/206; 180/220 - ring on pedal shaft driven with pinion gear
6131683 Electric bicycle, Masami Wada, 180/220; 180/216; 180/291 - transmission
6015021 Electrically assisted vehicle, Tatsuaki Tanaka et al (Sanyo), 180/206; 180/220 -
when starting or when pedaling hard =power mode, otherwise economy mode.

Direct Drive to Rear Wheel

Requires a second drive chain or belt to rear wheel that has a second freewheel to allow pedaling without the motor.
6011366 Electric bicycle, Seiji Murakami et al (Sanyo), 318/1; 318/139; 180/220; 180/231; 180/652 - belt drive pully added to rear wheel
5937964 Unitary power module for electric bicycles, bicycle combinations and vehicles, Richard A. Mayer et al (Currie) 180/220; 180/205 -
5433284 Electrical bicycle, Wen-Cheng Chou, 180/205; 180/220; 180/652; 280/214 - ring and pinion to motor shaft is at 90 deg to rear axle

Wheel Hub Motor

Adds unsprung mass and stronger gyroscopic forces.  Very inefficient when hill climbing.  May trip thermal breaker on long hill climb.
Hub motors are simple when only one is being used but there are restrictions on the frame size and brake size to accomodate the large size.
Rear-wheel hub motors preclude the use of internal-gear hubs.  Most preclude use of disk brakes. 

The simplest type of hub motor has a drum lined with permanent magnets attached to the bicycle wheel and a center assembly with a number of coils attached to the bicycle frame.  There is no gearing.  Note when the coils are not activated, i.e. the motor is not being used there will be "cogging" similar to how a stepper motor feels when its shaft is turned.  This is caused by the permanent magnets being attracted to the iron cores of the coils.

Geared hub motors do not have this problem because they have a freewheel feature.  That also means the geared hub motor can not provide regenerative braking like the simplest type of hub motor.

The speed provided by hub motors varies by motor make, power-rating and wheel size. 
552271 Electrical Bicycle, Ogden Bolton Jr, Dec 31 1895, 180/220 ; 310/67R - hub electric motor
6286616 Hybrid drive mechanism for a vehicle driven by muscle power, with an Auxiliary Electric Motor, Michael Kutter, 180/205; 180/220; 180/655 -
6093985 Non-brush type direct current motor for electric bicycle, Tun-I Chen, 310/67A; 310/66 - in front hub brushless DC motor
6015021 Electrically assisted vehicle, Tatsuaki Tanaka et al (Sanyo), 180/206; 180/220 -
when starting or when pedaling hard =power mode, otherwise economy mode.

Jack Shaft Drive to Rear Wheel

2008/0066984 A1 Electric Bicycle with Jackshaft Assembly, Ronald Holland, 180/207 - Claims better than the other methods, but at the expense of complexity.
7108097 Power assisted recumbent bicycle and power unit, Brent Cecil Bolton et al (ECO Speed),  Sep 19, 2006, 180/205 ; 280/288.1
a jackshaft allow use of the rear wheel gearing
3280932  POWER-ASSISTED BICYCLE, MOULTON Oct 1966 - engine to rear wheel
3429584  THREE-WHEELED VELOCIPEDE, HENDRICKS Feb 1969 - tadpole with friction brake to road
3664684 LONG TWO-PASSENGER CYCLE May 1972 - 2-wheel recumbent with outside bearings on pedals
3827519 VEHICULAR EXERCISER APPARATUS Aug 1974 - delta trike with single speed motor drive to rear wheel
4108460 Amplified cycle steering system Aug 22, 1978 - second headset and linkage for steering, uses jack shaft for pedaling
4280581 Motor and pedal driven bicycles, L.A. Rudwick, Jul 28, 1981 - jack shaft motor drive in enlongated standard bike
2331976 Motorcycle Oct 1943 - pedal or gas engine w/jack shaft
2457430 Electric Bicycle Dec 1948 - sprocket drive to chain near pedal gear
2491076 Propulsion of Cycles Dec 1949 - engine drives chain near pedal gear
3891044 Bicycle Propelling Means Jun 1975 - friction drive on side of tire
3905442 Electrical Assist Unit for Rider Propelled Vehicles Sep 1975 - front wheel friction drive
3912039 Bicycle Drive Apparatus Oct 1975 - friction wheel drives metal disk on front wheel
3915250 Axillary Drive for Bicycle Oct 1975 - two motors friction drive rear wheel
3921741 Bicycle with Electric Motor Assist Nov 1975 - hub e. motor
3961678 Simple electric bicycle Jun 8, 1976 - rear wheel friction drive
3991843 Cycles Nov 16, 1976 - pedal crank drive
4072204 Cycle gear selector Feb 7, 1978 -  related to 3991843 (Lucas) - e motort drives rear hub which has internal gears
5036937 Exercise vehicle Aug 6, 1991
5242028 Motorized bicycle drive system, L.J. Murphy Sep 7, 1993 - e. motor drives pedal crank
5474148 Bicycle with electric motor Dec 12, 1995 - complex way to vary the amount of assist
5509678 Recumbent bicycle Apr 23, 1996 - 2-wheel
5853062 Recumbent electrically power-assisted bicycle Dec 29, 1998 - e. motor drives pedal crank
6062329 Pedal bicycle having an auxiliary power means May 16, 2000 - engine chain drive to rear wheel
6070894 Arm-powered wheeled vehicle with bicycle-type cranks Jun 6, 2000
6352131 Bicycle's power train Mar 5, 2002 - e. motor drives pedal crank
6591929 Motor-assisted bicycle and power unit Jul 15, 2003 - pedal crank drive

Direct vs. Indirect Steering

Direct steering has the hand grips connected to the hub with a short solid tube.  The wheels are interconnected with a link that sets the toe in.  Strong simple and reliable.
Linkage steering has a handlebar with links to the two steering wheels.  Has Ackerman geometry (WikiRC Tek).  Improved geometry and maybe less effort required??
Indirect steering allow relocating the steering, like in a Velomobile.
2009/0224524 A1Lean to steer recumbent vehicle, Lawrence Rathsack, - tadpole design
6402174Recumbent tricycle with controlled wheel and body lean, Alan Maurer 280/267; 280/282; 280/288.1; 280/269; 280/266 - tadpole
4360244 Miniature coaxial connector assembly, Nov 23, 1982
4373740 Three-wheel vehicle, Feb 15, 1983 - tadpole
4432561 Tricycle recumbent, Feb 21, 1984 - tadpole lean to steer
4456277 Tricycle, A.E. Carpenter (Cyclodynamics),  Jun 26, 1984 - tadpole Velomobile
4460190 Hand propelled wheelchair, Jul 17, 1984
4469344 Tiltable three-wheeled vehicle, Sep 4, 1984 - looks like add on to regular bike
4624469 Three-wheeled vehicle with controlled wheel and body lean, Nov 25, 1986 - car size
4634137 Tricycle and drive therefor, George T. Cocksedge, Jan 6, 1987 280/256; 280/269; 280/282 - tilting tadpole
4650213 Vehicle body inclining apparatus of vehicle, Mar 17, 1987 - car size
D290451 Ornamental design for a tricycle, (Skeeter Trike,) Jun 23, 1987 - tadpole
4903857 Leaning vehicle with centrifugal force compensation, Feb 27, 1990 - pedal power 2-wheels in front - maybe addon to regular bike
4921263 Inclinable vehicule, May 1, 1990 - delta i.e. 2 rear wheels
4998596 Self-propelled balancing three-wheeled vehicle, Mar 12, 1991 - delta
5263732 Three wheel recumbent vehicle, Jerome E. Harmeyer, Nov 23, 1993, 280/288.1; 280/103; 280/112.2; 280/259; 280/263; 280/282; 280/772
- tadpole with space frame & Ackerman geometry
patent 5263732 tadpole tricycle
                space frame
718440 Steering Apparatus for Vehicles, H.J. Elsner, Jan 1903 - the projection of all axles must intersect at a point
2147732 Two Wheeled Vehicle, E.S. Boynton, Feb 1939 - chain stering drive to offset front wheel
3753577 Sporting Velocipede, R.G. Robinson, Aug 211973 - tadpole with seat much lower than rear axle line
3913929 Low Center of Gravity Cycle, Oct 1975 - tadpole with crankshaft for pedals
3981516 Bicycle and tricycle of low wind resistance and of low center of gravity, Sep 21, 1976
4283070 Recumbent bicycle, Aug 11, 1981
4373740 Three-wheel vehicle, Feb 15, 1983
4410198 Human powered vehicle, Oct 18, 1983
4432561 Tricycle recumbent, Feb 21, 1984
4456277 Tricycle, Jun 26, 1984
4548421 Recumbent vehicle, Oct 22, 1985
4659098 Semi-recumbent bicycle, Apr 21, 1987
4878684 Recumbent bicycle, Nov 7, 1989
4993733 Three wheeled recumbent cycle, Feb 19, 1991
5154437 Vehicle steering system with independent steering for each wheel, Oct 13, 1992
5544906 Human powered recumbent vehicle, Aug 13, 1996 - tadpole with dual ladder frame
5568935 Recumbent cycle with improved drive and steering, Oct 29, 1996 - delta
5762351 Multi-track vehicle with lock and drive lean control system, Jun 9, 1998 - tilting non-recumbent
6062581 Leaning recumbent tricycle, May 16, 2000 - very high seat position tadpole
Called By:
6581947 Steerage of a vehicle, Jun 24, 2003 - hand powered tadpole
6709013 Land vehicle with lever steering, Mar 23, 2004 - for-aft levers steer 2 front wheels
D493391 Three wheeled vehicle, (Huffy) Jul 27, 2004 - kids tadpole with rear axle steering
7017685 Combination pedal/motor driven tricycle, Mar 28, 2006 - delta can stand or rear end for parking
7044491 Tricycle, May 16, 2006 - child's trike w/ rear wheel steering
7188853 Tricycle, Mar 13, 2007 - child's trike w/ rear wheel steering

Wheel size

The larger the diameter of the wheel the lower is the rolling friction and the easier the bike goes over bumps.  Also larger wheels have the hub higher off the ground and hence better ground clearance.  But smaller wheels change gearing to more torque and that's better for hill climbing.

Related Web Pages

Motorized Bikes - and Scooters
Bicycle Science
Cars - including 3-wheelers
Tilting Three Wheeler Patents
Gilbert DC Motor for Erector set
MESCO 1011 Toy Engine
Electro-Magnetic Toy Engine
No. 6 Dry Cell
Weeden D.C. Motor - really a generator


Bionx - electric hum motor kit - does NOT work well for hill climbing since  you need some speed before it kicks in

Tadpole Trikes (pg. 1) - ACE Spider, Actionbent, Angletech, Anthrotech, Berkut, Berserker, CarbonTrike, Catrike, Challenge, Curve, Cycle Genius,
EZ Tadpole, Freedom, GNAT, Greenspeed, Härmäpyörä, Innesenti, MMX1, KMX, Logo, nlSolar, Optima, Pirol, Quix
Tadpole Trikes (pg. 2) - Red Rim C1, Roller, Rotator, RunAbout, S-4 3WD, Scorpion, S & B, Sherer, Sidewinder, SK3 Mountain Trike, Spitfire,
                            Stein Trikes,
ST Trikes, Swift, Teesdale, TerraTrike, Trice, Triclops, TriCruiser, Trimuter, Tripendo, Trisled,
VogaBike III, Windcheetah, Zenit
Velomobiles (enclosed bikes) - Aurora, Glyde, Bricycle, Aerorider, Alligt Alleweder, Flevo Alleweder, Birkenstock, Bries, Cab-Bike, Go-One,
Leitra, Leiba, Lightfoot, Mango, Milan, Quest, Sorcerer, Versatile, Waw

Motor Bicycling - forum 2 & 4 stroke engines
Sick Bike Parts - Shifter Kits that use a Jack Shaft for 2-stroke gas engines
EV Deals - electric vehicles and conversion kits
Advanced Motors & Drives - golf cart and small EV motors & related
Cloud Electric - Motors, Controlers, and various kits.  Package Electrathon CloudEV/Scott Upgrade 1.6+ HP Motor, Alltrax Programmable Controller
High Tech Bikes - ready made and conversions
Recumbents.com - mostly about recrod breaking but also a lot of general info
Abundant Adventures - Mountain Tamer chainrings for retrofitting gearing into the 16 tooth area
Schlumpf Innovations - Mountain Drive Planetary gear & other crank gearing systems  $600 but very high quality
Hostel Shoppe - bikes & parts
Light Foot Cycles - good notes on electrical assist and engine assist
10 AH LiFePO4 Battery rated for 50 Amps continuous (100 Amp surge) - holders for making packs and series or parallel metal links  - 12.8V Pack (10 to 15.2 V) - PCB - Charger
ECO Speed - Electric Mid Drive (EMD) for recumbents (used by Lightfoot)
Electro Portal

LiFePO4 38120P Battery: 51.2V 10Ah (512 Wh, 60A rate ) with PCM (48.0) - might make possible a 2-wheel bicycle w/Jack Shaft Gearing (Stick Bike Parts).
Battery mounted above rear wheel, motor just above crank, jack shaft on seat frame tube.
Maybe turn motor 90 degrees and use worm drive as part of gearing thus making for a narrower front profile.

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page created 4 Jan 2010.