Racing at Purmerend

Last week we had an event in Purmerend at a closed off industrial area. I raced my 50 and my dad's CB72 to compete in 2 classes. This was the third event I rode the 250 to see if I would like the "big" bike.
Action shots are thanks to Lea langezaal, the club photographer, see more of her pictures on the CRT website
The number 2 bike is an Aermacchi.

Unfortunately in the last heat, the motor shot out of gear, or so it seemed, I was quick with the clutch, had a look if I could see anything wrong, but nothing to see. I tried to release the clutch gently, but that didn't feel right, so I quit.

Back home, we took out the engine, my dad has three of these bikes, and raced them with friends. Back then, the bolt that alligns the shift fork with the shift drum had broken before, so that was believed to be the problem. But when we opened the clutch cover, the real problem became all to clear: broken primairy chain.

This is a "normal" thing to happen to a CB72, especially when raced, but usually the chain cracks the cluch cover making it clear what happend, in my case it didn't even leave a scratch on the inside.
Fortunately my dad had a new stronger chain set ready to fit to this engine, just didn't get round to fitting it yet.