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1981 cb750k advice for Sprocket and chain replacement & general quesiton('s)

PRIMEWORKS

CB750 Enthusiast
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So I'm currently looking to replace the worn/dirty front & rear sprockets along with the chain on my 1981 CB750K DOHC but I'm having a bit of trouble finding exactly what I want.

Currently the bike has: 18 tooth front sprocket
46 tooth rear sprocket
108 link chain

A majority of my driving will be in city but I'd ideally like a sprocket ratio that gives me the best of both worlds (being acceleration and top speed) and seeing as this is my first CB I'm not sure if the current sprocket ratio is going to give me that. Also I've seen that a lot of people seem to prefer a 530 chain over a 630 chain and I'm not sure which one I currently have on the bike or what the exact difference is between the chains. If I have a 630 chain is it just a matter of me buying a 530 chain? or do other components require replacement aside from the sprockets? Also I've heard that an X ring chain is better than a O ring chain? Any advice would be REALLY appreciated as I'm looking to purchase from Dime City Cycles as they currently have free shipping this weekend!

A second question I have is regarding tuning with the carbs. I recently cleaned/rebuilt my carbs with a general rebuild kit from Dime City Cycles and I just bought a 4-1 Mac exhaust and am looking to install it but I'm wondering if I'm going to have to replace the jet's with something other then what came in the kit. I don't plan on running pods as I want a headache.

Here is the link to the rebuild kit: (k&l kit from Japan): http://www.dimecitycycles.com/vinta...da-cb750f-carburetor-rebuild-kit-18-2554.html)

Thanks !
 
O-ring chain is fine if you buy a quality one. With the teeth numbers you got 530 chain, 630 only in '79. Harder to find it as not used much. Too big anyway and not needed. The ratio you have already splits performance and top speed, don't really know what more you could be looking for there. Will run 120 mph as it is. Less speed and engine overheats, they need oil cooler as it is in summer and a hot state like me in Texas. Meaning you need a bigger motor not more ratio as you will suffer either way you go with ratio. The chains are often endless with no master so can limit you as well. 630 chain FYI has sprockets matched to it, all 3 needed if you change to it. I WOULDN'T, the CB1100 @ 50% more power uses 530 too.

The CV carbs self adjust jetting to a point, nothing like direct lift which require changes with any mods. Mac headers not real HP boosters anyway, not known for big power increases, I'd start with same OEM jetting. If you don't have a really primo engine with 170 psi compression you may need to LEAN the jetting out, these are old and many do not run well because of the commonly overlooked valve clearance issues that slow them down and screw your jetting efforts up muy malo. Why so many have fits doing it.
 
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