10/16/2026
Who doesn’t have a story about starting a 500 Yamaha? My shin bone will still hurt every now and then when I think about my old TT500🇺🇸
This is a fun read. Take a minute and maybe reminisce a little.
There is a reason every story about this engine starts with somebody limping.
A 500cc single builds enormous compression in one very large cylinder. When you stand on the kick lever and the piston comes up against it, the engine simply stops turning. All the energy you put in has nowhere to go, so it comes back up the lever, and the lever comes back up at your leg.
People broke ankles doing this. It was common enough that riders developed a ritual around it.
The ritual goes like this. Pull the decompression lever on the handlebar, which cracks a valve open and lets the pressure escape. Ease the kick lever down slowly until you feel the piston come up to compression. Release the decompressor. Now you are standing at the top of the stroke with the engine ready, and from there one committed kick with your whole body weight takes it through.
Get the sequence wrong and the bike kicks back.
Everything else about the engine is the opposite of difficult. Single overhead camshaft, two valves, air cooled, modest compression, and a torque curve so flat you could ride most of a trail without touching the gearbox.
That was the point. In 1976 off-road competition belonged to two-strokes, which were light and fast and needed rebuilding constantly. Yamaha went the other way with something that pulled from nothing and did not wear out.
The same engine went into the XT500 road bike and later the SR500, which Yamaha kept building for decades.
And people still start them the same way, with a lever on the handlebar and a careful foot.