Project Veronica Part 7: Engine Rebuild

Hey Guys, Matt here with another installment in the Project Veronica build, this week we look at the heart and soul of the Yammy, the air-cooled three-cylinder 750cc powerplant!

Originally when I bought the bike, it ran fairly roughly. Being a 40 year old motor, the components inside were well and truly worn. So, my buddy Ron tackled the rebuild starting out with a sandblast of the motor back to bare iron.


From there, the tear-down could begin starting off with complete disassembly. We found the head, valves and block to be in good condition, however the rest was fairly used and would be risky to re-use.

A Newtronics electronic ignition system will also be fitted along with a bunch of stuff:

  • New pistons 0.25mm overbore
  • New Rings
  • New Gaskets and seals
  • New primary chain
  • Carbon fiber Barnett Racing clutch
  • Mild decking of the block to raise compression ratio
  • New main and conrod bearings
  • New cam chain tensioner
  • New aluminium bolt kit

Here's the block powdercoated black but I'll need to shave the paint off the top four large fins.


As of right now, the cases are apart, with the much better condition transmission in place, but we're now getting to the nitty-gritty of the engine rebuild. I'll keep you guys posted, exciting times ahead!.

Matthew La Scala


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