hi , it is a 75 cb550- it idles and runs very good all through the range...
here are two cb750's with stacks also...the top 72 cb750 (green) has been on the road and it is increadably well carburated all through the range and i can not get over how smooth/low it idles,about 900 rpm. the bottom cb (72 also) has run(it seems fine)on the bench but is not completed so it has not been on the road yet to verify/ck jetting...
of course you need to cover the basics, engine integrity is critical,type exhaust system, then the proper settings (valves,timing,aau operation). it seems most of the jetting problems with the carbs is in the mid range so go much richer and the same with the mains..stock pilot may be ok,if pilot air screw is in less than 1/2 turn go up one size.....one thing for sure is you can make them run fine with stacks..
what bike specs are you interested in? i have the stacks to sell also if anyone is interested
good luck, joe@ vcycle
www.joesvcycle.net