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Carb restoration and air filters

Jackalow13

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Hey guys! Im new to building bikes so extra help would be appreciated! I just picked up a '74 cb and I'm going to clean up the carbs and put on some pod air filters. What do I need to do to do this and would I need to tune the carbs differently? Thanks a ton!
 
Maybe one size bigger main jet or leave it like is if stock exhaust still used. Need to go more if a 4-1 header used.
 
You are going to have to see how it runs first. Jetting isn't a one size fits all deal. Too many things affect jetting... engine condition, any changes from stock...internal, induction, exhaust, temperature, altitude, fuel quality, etc all contribute to jetting needs. You need to run it and see if it is lean/ rich up high, mid range, part throttle and idle. You have main jet, needle position, idle jet and idle screw adjustments. Just pods with a stock motor you may only need a very slight adjustment or non at all. Keep an eye on the plugs.
 
'Too many things affect jetting... engine condition...'

Stop right there.

Somebody who actually calls that out, how rare is that? So many just simply assume that the same setup fits them all, yet with bikes this old MANY of them are not in decent running condition, then invariably owner goes to blaming the 'wrong jetting numbers' given to him. The incompetency issue I get into with so many guys who would rather fight than think for a second about the bike's issues.

The same problem but even worse with the later DOHCs which if motor has fallen off in power due to age will not lift the CV slides at all and richening them up only makes the problem much worse, yet they insist that has to be the problem. Enter the bottomless abyss.

I so X2 that last post........................every one is different, and simply assuming they need to jet up can be your worst nightmare. I've actually fixed a few by jetting DOWN, it happens. Common on engines with garbage flowing exhausts that actually flow worse than stock but loud as hell, they simply HAVE TO BE lean according to the conventional wisdom. NOT SO.

Valve and ring seal being off will kill you on carbs on these engines. Yet everybody tears the carbs down first....................I actually bought and sold DOHCs there for a bit based on that, the people working on them messed them up even worse and easy to bring them back to running like a bat outta hell for almost instant $500-$1000 or more profit in 3-4 days.

Shouldn't even touch carbs until the engine's compression has been run to let one know what kind of shape the engine is in.
 
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