Topic: Clarification of “full throttle opening stopper adjustment” procedure

[johnny550]

The service manual for my 76 CB550 describes adjusting the full throttle stopper screw so that “the throttle valve extends 0 ~ 1mm above the throttle bore in the full open position.” I took this to mean adjusting so that the throttle valve is just out of view when looking though the carb, but the corresponding photo in the manual seems to show otherwise - measuring 1mm from the top of the hole on the side. Am I reading the image wrong, or is the image just poorly drawn? Or is this the correct procedure?

One thing I do notice with my bike is that it is difficult to achieve full throttle without adjusting my hand position on the grip, and I’m wondering if the throttle valve does not actually need to extend completely outside what I thought was the “bore”.

Does anyone have any insight on this?

[69cb750]

You want the slide to clear the bore, that's all.
Old cables get dry and need more effort to move, replace or lube.

[Scott S]

 This thread may help with setting the slides, throttle and bench syncing:

http://forums.sohc4.net/index.php/topic,184299.0.html

[HondaMan]

Honda unabashedly made these Fours with the "two-grip twist" throttles in those days, because they were [overly] concerned with the then-new and powerful  Fours outspeeding rider's abilities. It was a throwback to the days of the Dream series of bikes with their arcane slider throttles that also took 2 handfuls to fully open up.

You can improve on the situaiton a little bit by laying some solder in the grooves of the twistgrip pulley to make its base circle slightly larger. The 500/550 suffer more noticeably from this situation becuase its powerband doesn't start until 1/4 throttle!