When building my CB750 motors, I have always replaced the cam chains with the Tusbaki heavy Duty cam chains. I've never really even considered anything else, and I have never had a problem with them.
I recently stumbled across that the CB750 cam chains are a standard #219 chain, and that in other racing circles (namely 100cc Kart racing) the D.I.D. #219 DHA chains are the ones that everyone uses. I know that I always prefer to use the D.I.D. chains for my final drive chain, but I have never considered using a D.I.D. as a cam chain.
The main reasons for considering the D.I.D. is that it is cheaper, it is readily available, it appears to be the preferred chain for many racing applications, and possibly the #1 reason is that it is available in a 'trick looking' gold-on-gold finish -- and we all know that we all need a little more invisible bling tucked away in our motors.....
But all kidding aside, does anyone out there have any experience with running the D.I.D. #219 chains as SOHC CB750 cam chains?
peace and grease,
Steve