77 CB750A - Should I stay with 630 Chain or go to 530 like 1976 Model?

I have a 1977 CB750A with a chain showing tight spots when I go to
adjust the chain, making it hard to adjust properly. When it's
set up for the right amount of play and I rotate the tire, the
play gets tighter in certain spots. I'm guessing it's a sign to
change the chain. My problem is a 630 Chain costs alot more than
a 530 chain. Should I Replace the 630 with a good quality 530 chain
and sprockets or stay with a new 630 chain and sprockets.

One thing to keep in mind, I'm told that newer high powered sport
bikes don't use 630 chains anymore but use 530. Some say the size
and weight of a 630 chain robs power from the bike. 530 Chains
have gotten alot better since the 1970's.


The 1976 CB750A used a #530 chain that had 104 links, and the
1977/78 CB750A uses the #630 chain but only had 88 links. With
the #530 chain the front sprocket had 17 teeth, and the rear
sprocket had 48 teeth. The #630 chain front sprocket had 15
teeth, and the rear sprocket had 42 teeth. The ratio of the
#530 gears and the #630 gears are almost identical.

Who has cheapest good quality chains on the web for both
530 and 630?