Topic: Advice on syncing carbs - Cb750k5

[Jarrett_Honda]

I get my carbs within 2 cmhg of each other which I believe is close enough. The bike idles between 1000 and 1200 rpm.

The bike is able to stop and start easily while the bike is warm. Once the engine cools I have trouble starting the bike without increasing the turns in the idle adjustment screw.

How do I adjust the carb to where the idle screw would be in the desired setting to provide enough air to start?

Everytime I make a change to the carbs the idle would drop or rise in which case I would adjust.

My timing is good
Electronic ignition
Compression good
New jets and clean carbs
Fresh fuel
New coils and spark plugs

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[TwoTired]

These bikes don't have a computer mixture control, or an automatic choke, or a fast idle cam coupled to the choke.
Due to poor inefficient cold atomization of the fuel, you cannot get an idle setting that is good for both cold and warm operation.

SOP is to set the idle for warmed up operation and hold the throttle open a bit during the warm up period.
Others twiddle with the idle knob for cold and then readjust after warm each time they operate the bike.
Another way to go is to install a "cruise locK" on the throttle that will hold the throttle at fast idle while you wait for warm up.

Nothing says you can't drive the bike when cold.  Just don't flog it until warmed up.  While riding, you normally have your hand on the throttle and can maintain faster idle while driving.

It is normal to hold the throttle open a bit during initial start, Cold or hot.  Some call that, "high operator work load" these days.  It was routine when the bike was introduced.

[Jarrett_Honda]

These bikes don't have a computer mixture control, or an automatic choke, or a fast idle cam coupled to the choke.
Due to poor inefficient cold atomization of the fuel, you cannot get an idle setting that is good for both cold and warm operation.

SOP is to set the idle for warmed up operation and hold the throttle open a bit during the warm up period.
Others twiddle with the idle knob for cold and then readjust after warm each time they operate the bike.
Another way to go is to install a "cruise locK" on the throttle that will hold the throttle at fast idle while you wait for warm up.

Nothing says you can't drive the bike when cold.  Just don't flog it until warmed up.  While riding, you normally have your hand on the throttle and can maintain faster idle while driving.

It is normal to hold the throttle open a bit during initial start, Cold or hot.  Some call that, "high operator work load" these days.  It was routine when the bike was introduced.

Thank you for a detailed response. I learn someone new everyday.



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