58 Tiger Cub Motorcycle

FRS 106, Michael Littman – Spring 2017

February 28, 2017 (Tuesday, Week 4)


  • Updates on shop progress
  • Dynamometer Demo
  • Readings

Bottom End

  • cleaned engine case
  • used arbor press to remove sprocket bearing, took seal out (needs replacing)


  • need to go to bunker to find some new parts (oil reservoir cap)


  • finding lights online
  • polished parts


  • remeasured engine cover
  • completed Creo tutorial


  • measured forks
  • removed wiring from handlebars, removed grips from handlebars


  • worked on taking apart rear struts

Top End

  • sandblasted and scrubbed 
  • next step: cut gaskets


  • opened and cleaned rear hub
  • replaced rear wheel bearings
  • *important to make sure all parts are clean before they go to the powder coater

Dynamometer Demo

  • force- units: pounds, Newtons
  • torque- rotational force (foot-pounds, Newton-meters), r*f
  • power- energy per time (Watt, foot-pounds-per-second), or force*velocity
  • work- force*distance
  • one horsepower = 33,000 foot-pounds/minute (about 750 W)
  • dynamometer- what is the torque? what is the power?

DeProny brake, or brake dynamometer

  • measures torque vs rpm (angular speed)
  • find angular speed at which your motor generates the most power (which is why we have multiple gears)


  • Torque is turning force
  • Work is force*distance
  • Power is force*velocity


Zen, Chapters 7&8

  • Motorcycle references
    • Jets— oversized vs standard (use oversized/ pilot jet when idling)
      • size of hole determines air flow vs gas flow
      • At higher altitudes, oxygen is lower— needs less fuel
    • Spark plug— when “fouled”, covered with carbon— too much fuel
    • Chain— is running “hot and dry”— evaporating lubricant immediately
    • Cam and Tappets— made of hardened steel, because they take the brunt of the force
    • Need to adjust tappet/ cam shaft clearance when cold (when parts are warm, it stretches)— valves need to close fully
  • Content
    • revisiting classical/ romantic 
      • understanding thoroughly loses some beauty (Mark Twain—lost the beauty of the river), but there is also beauty in learning how things work
      • reconciling two viewpoints
    • “ghost of rationality”
      • rationality is not always beneficial
      • ethics— can rationality be applied? (utilitarian)
    • effects vs causes
    • “He was systematic, but to say he thought and acted like a machine would be to misunderstand the nature of his thought. It was not like pistons and wheels and gears all moving at once, massive and coordinated.”
      • whole vs individual
    • Steel
      • “Steel can be any shape you want if you are skilled enough, and any shape but the one you want if you are not.”