Honda-SOHC

SOHC.co.uk Forums => CB350/400 => Topic started by: alfiembra on May 25, 2022, 03:33:58 PM

Title: 400/4 float heights
Post by: alfiembra on May 25, 2022, 03:33:58 PM

I’ve recently overhauled my 77 400/4 carbs with a kit from the USA, from 4into1.com had the kit for many years but never fitted it. Now that I’ve done it the float height is concerning me slightly, the bottom of the floats do not sit parallel to the face of the float bowls but neither did the originals before I took them apart. When I measure from the face of the bowl to the lowest point of the float it measures 21mm which is what I understand it should be, but at the high end of the float it measures 23/24mm. Should the float be a constant 21mm straight across or does this sound right?

Also any tips on setting them up statically before refitting them.

Thanks in advance.

Title: Re: 400/4 float heights
Post by: Nurse Julie on May 25, 2022, 04:08:35 PM

Set as per following at 21mm for a 400/4
http://www.sohc.co.uk/index.php/topic,23233.0.html

Title: Re: 400/4 float heights
Post by: Nurse Julie on May 25, 2022, 04:16:35 PM

And here is Bryan's tutorial on how to bench sync prior to fitting.
http://www.sohc.co.uk/index.php/topic,17769.0.html

Title: Re: 400/4 float heights
Post by: alfiembra on May 25, 2022, 11:30:04 PM

Thanks Julie I’ll set the floats up using your guide. I’m not sure I follow Bryan’s guide for setting the slides will need to have another read on that. If I’m understanding it correctly after undoing the tick over screw you set the lowest slide with the drill bit shank as a feeler gauge, do you adjust that slide with the slide adjuster then set the idle screw to that position? Then adjust the rest to match. The way I read it you set the slide height with the idle screw and then adjusted the rest with the slide adjusters. Probably my bad. Thanks again.

Title: Re: 400/4 float heights
Post by: Sesman on May 26, 2022, 07:10:53 AM

Correct. Set the first slide till it’s just touching with the slide adjuster, then use the idle screw to lift it 1/16th. Set the remaining slides using the slide adjusters without touching the idle screw.

Title: Re: 400/4 float heights
Post by: Bryanj on May 26, 2022, 08:28:46 AM

The point is that slides need to be able to touch the base thus totaly closed to start, then use big adjuster till one is open enough to use the drill bit as a feeler, smallest available 1/16 max and preferably new so no damage on shank.
Then set other 3 to same and finally check that all close with big screw wound out.