1980 CB750F Carb decisions, would appreciate some experienced input!!!

flatpick13

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Will any of the more experienced folks on here (maybe amc or dirtdigger) provide some advice on whether I should put in the effort to repair, rebuild, and re-jet the stock CV carbs or should I look at a replacement? I'm planning on using pod air filters and either a 4-into-1 (Delkevic) or a 4-into-2-into-1 exhaust (probably Ripple Rock Racers). I'm not super worried about horsepower, this is just an around-town cruising bike, but I would like it to run well.

I'm at the point where I need to rebuild or replace carbs, I know the CV is not a fan of anything but the stock airbox (and sometimes not even that...). Engine is fully rebuilt, every bearing and seal replaced, head resurfaced, valves checked/replaced, timing lined up and now I just need carbs to get fuel and air (and an exhaust...).

IMG_2786.jpg

The carbs on the bike had some of the cast pieces on the throttle body broken, I haven't been able to find replacements pieces without buying another carb... I've been looking at either buying a cleaned CV carb on e-bay and struggling with modifying it to work with pods, or waiting and saving up to get Mikuni RS carbs (though I'm not sure which size for the DOHC, I've seen a few sites that point me to RS38s...).

Are there any recommendations one way or the other? Or recommendations on other reliable replacements besides Mikuni that don't cost $1,000+?


Thanks!
 

amc49

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38s are too big for a 750 unless fully ported head and wild cams in my view, more like 1100 carbs. The aftermarket carbs if chosen right will make about 10+ hp right off the bat as they are direct lift. 20 hp. with a full tilt engine.

The CVs will work but since the vacuum has to be up to work them why you never get as much power out of them as direct lift which will work as low as under one inch of vacuum-CV won't.

If you go to http://www.cb1100f.net/ and enroll you will find plenty of people that have changed carbs on them. Pay special attention to somebody there posting as 'Captain', he roadraces a 200 hp. custom DOHC.

At the cb750c.com site somebody named 'genesound' knows plenty as well.
 
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user8086

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Cv 42 or Cv43 will work.. you will need a decent assortment of jets and a ton of patients.. we have rebuilt many the latest on this 1980 SuperSport 750f
 

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