Mythbuster: continuing project thread of my 1303 '75

[Wally]

Well, not everything works out with my builds too as these pics prove:



Torched a cylinder and head big time!
Root cause probably the one-off cast cylinders. No matter how thick the walls were...
Partly also my own fault as I didn't retorque the heads more often, which would have been more wise because the cast cylinders did need more 'seating' then I usually am customed to. I noticed this when disassembling the engine: head torque was too little on the other cylinders, so thats probably what started this.

Still, all other cylinders also showed a much larger bore up top then bottom of the cylinder (!), so they just didn;t stood up to the cylinder pressures I ran anyways. That also explained the excessive breathing I experienced: the rings just couldn't keep it sealed up top in the cylinders..

Anyways, for a 'quick' fix I bought a set of the AA 98mm birals so I could reuse at least my pistons.
Head is fixed at the moment already and I am reassembling the engine again