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Pilot Screw Adjustment 1981 CB750C

footshooter5

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Hi all,

Long time lurker here! Recently picked up an '81 CB750C for super cheap that clearly needed some work...I've made it my summer project for this year, thanks to my wife :D The PO didn't really do my any favors, left it uncovered, in the rain, removed the carburetors and messed around with them and removed all the fuel lines too...

Anyway, I've been reading through the Clymer manual regarding where to start the adjustment for the pilot screws on the carbs (I think they specify 1 1/2 to 1 3/4). Mine currently sit at approximately 3 1/2 (for all 4 of them), but I really have no idea if this is remotely correct or the PO was just fiddling around. I know the proper technique is to use a tachometer and adjust them looking at whether the RPM goes up or down and then adjust the throttle stop screw as well, but hopefully someone on here can give me an idea if this is not an unreasonable number of turns to be out.

Thanks in advance, and looking forward to being a regular contributor to the forum!
 
The service manual spec is an emission setting, you can go 2-2 1/2 max, needing more says your carbs have clogging in the idle circuits. Each one separately turned all the way to closed must kill that cylinder or again you have carb issues.

If carbs were off while left open in the rain the motor may be scrap and common when people do that.
 
download a Honda factory manual on your model, and ditch the Clymer. get a good battery, make sure the oil is full, spin it over and see if it makes any horrible noises, If not check the compression, if its within spec then start with rebuilding the carbs, and cleaning out the fuel tank. Good luck
 
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