Re: Carb Syncing and Jetting

Posted by Lucky 1 on Jul 11, 2011; 4:38pm
URL: http://vintage-and-classic-hondas.81.s1.nabble.com/Carb-Syncing-and-Jetting-tp2985119p3159709.html

You said you have a "custom" airbox.
If the airbox has less restriction it will want to run leaner and that can make popping and spitting back
when trying to open the throttle. It can make backfire also when trying to advance the throttle.

Usually with a performance exhaust(less restriction) and less air filter resistance you would have to increase the main jet ,raise the needles  and also richen the air pilot screws. ANY combination thereof.

If you just had after market exhausts and NO air box modifications then you can get by with just a air pilot screw adjustment. No extra air in - no extra gas needed.

The fact that you found a bent pilot airscrew makes me think other things could be not right by that same heavy handed person that did that.

One more thing...The cam chain tension must be performed BEFORE valve adjustments.
The cam chain adjustment MUST be done when the crank is in the correct position(about 45º) ATDC on some HONDA's BUT CHECK THE BOOK!!!
Also Valves have to be adjusted with the crankshaft in the correct position.
CHECK THE BOOK.

You cannot do any of this correctly without the workshop manual.

I am a ex dealer mechanic from those days.