Topic: '70 CB750 carb dilema

[major domo]

The carbs on my 1970 CB 750 are missing the caps (screws?)  that cover the carb sync port where carb vacumn gauges attach. There is no part # listing for these, and a major supplier of NOS Honda parts says they are NLA. Anyone out there have a set (4 needed), or can reccomend a substitute? Photo attached for reference. Thanks in advance!

[flybox1]

IIRC, they are M5x0.8mm x 6mm

Bolt depot has some standard and socket screws that would work unless you are looking for used OEM stuff.
https://www.boltdepot.com/Product-Details.aspx?product=15644

Im sure I have a set in a bin somewhere if you prefer.

[Johnie]

Keep in mind there is a thin washer on those 4 sync screws too. They actually look like a crush washer as you sure don't want a vacuum leak at those screws.

[flybox1]

Keep in mind there is a thin washer on those 4 sync screws too. They actually look like a crush washer as you sure don't want a vacuum leak at those screws.

Isnt it paper or fabric of some sort?

[harisuluv]

It's an aluminum crush washer.  The only fabric type washer on the carbs is the red one on the float valves.

The aluminum crush washer applies to the brass type sync port screw, but I have also seen K0 carbs that come with an aluminum sync port screw, similar to those on the 77-78 PD carbs sans the crush washer.

[754]

I think brass screws are till 76 and PD uses alloy..