Own a Japanese Thumper (aka Yamaha SR500)

One of our members is selling the last of his collection of 1978 Yamaha SR500 "Thumpers"
 
See our Classified Section for the sales details.
 
1978 was the first production year for this classic machine. Cast much in the mould of the BSA singles of earlier vintage, this bike is light, nimble, responsive and generally just plain fun to ride.
 
You will find that it rev’s readily, delivering low end torque with a modest cruising speed of 90 kph at about 4000 rpm.
 
These machines are a derivative of the Yamaha off-road machines of the era, meaning that they are magneto / CDI ignition rather than the battery ignition which you find on typical road bikes. The magneto, and absence of an electric start, make the starting ritual a must…
 

  • Bike on the centre stand
  • Fuel on
  • Choke full on
  • Astride the bike, standing on the foot rests
  • Ignition on
  • Find resistance with the kick start lever. That’s approaching TDC
  • Using your weight, ease just past TDC
  • Raise the kick start lever all the way to the top
  • Full weight on the start lever and kick it all the way through

 
Experience shows that there are two worthwhile updates to the 500.

  • The first is a separate off/on switch for your headlight to stop the battery from going dead while you carry out the starting ritual.
  • The second is replacement of the vacuum activated petcock with a manual one to avoid putting a full head of gasoline above your carb float bowl when the spring in the vacuum petcock fails.
  •