Power Attachment

This idea is an easily detachable power pod for any type of cycle, able to lean with the machine and rise and fall with road undulations and be raised when no power is required.

Email me for any comments.

The attempt is to design an add on device that is:

• Easily attachable by sliding the pod onto a prefixed mount and applying a clip. This mount could be designed to fit almost any cycle rear fork as a bolt on mount or welded on as part of the frame.
• Not much wider than the bike it is affixed to and probably not any longer.
• Has a small drive wheel, possibly 12"-16". This allows for less gearing down. I estimate with a standard weed trimmer motor only a 4 or 5:1 gearbox will be needed. (Purchased from Scooter suppliers) The wheel could also have internal gearing of about 3 gears (EG Sturmey and Archer) if more range is required.
• The weight of the unit should give the required grip on the road. If not, the arm length could be experimented on so the unit drives itself onto the road as a result of the applied power giving additional grip as needed.
• Be able to be bump started. The motor could have no clutch for this to work - if the drive wheel can't get enough grip becuase of motor compression it may be easy to put downward pressure on the motor unit with your foot because of the position.
  

Also:

• Speed can be accurately predicted when fitted to any size bike and is not dependent on a certain bike wheel size as in hub motors for example.
• A bike handbrake lever can be used to raise/lower the pod onto the road. Some levers are sold EG from Greenspeed that have a locking pin - when the lever is pressed in, the locking pin can be engaged making the lever a handbrake and in this case raising the pod drive wheel off the ground.
• The unit ought be designed so as not to be fouled by the motion of the pedals.
• The design is probably most suited to petrol powered motors as all the power items are removed in one action. This is assuming batteries on an electric unit would not be mounted on the pod because of their size. (which may not be the case though)
  

The Arm could be:

• Single length tube - this requires the drive wheel be mounted on one side, not always easy using normal bike axles but possible using a hardened bolt. See http://www.ihpva.org/people/tstrike/building/frntwhl.htm
• 2 tubes. This may be a little hard to route the chain so the chain doesn't foul on the arm. Experimentation needed.

Possible negatives

The unit placement is close to where a normal bike stand is usually positioned so may interfere with it's operation.
There just may be a little sideways force applied to the bike when motor power is applied as the unit is not mounted directly behind
the bike.
There may be some bounce of the unit with irregular road surfaces necessitating the inclusion of a spring and/or shock absorber to
the arm.

[ Home ] [ Ally] [Stamp FAQ] [ HPV Index ] [ Design overview ] [ Bike 1] [ Bike 2] [ SWB Trike ] [Electrified 20" Tadpole trike] [ Childs Trike ] [ SWB Trike 2 ] [ Electric Trike ] [ RWS Trike ] [Delta Trike] [Childs Hi-Wheeler] [ Bike Trailer ] [Recumbent bike trailer] [Power Trailer] [ Steering Diags ] [ Steering Mounting] [ Kingpin Diags ] [Novel HPV Ideas] [ Australian HPV Resource ] [ Links ] [Power Assist] [ Unusual Vehicles ] [ Electric RC Models ] [ EV Circuit Diags ] [Tas HPV] [QLD PP] [Qld HPV] [Skycycle] [Bleriot] [Building HPV's] [Darryl] [Null Modem] [ Pedalezy ] [ USPD ] [Zeta] [Power Attachment] [Email]