Topic: CB400F Carb - springy thing

[The Lone Builder]

Last question - for now!

On my recently acquired CB400F2, I took out the carbs to see how bad they were. The answer is not bad at all.

However the springy butterfly thing on top of the main jet is missing on one carb - it shows on the parts fiche I have but has no number and hence no name!! Which I guess also means I cannot get a replacement.

What is this for and can I get by without it? Do any other models use this same part?

Thanks

[Bodi]

That spring thingy just holds the main jet and emulsion tube in. Unless someone has a junk carb bank and will give/sell you one you are SOL for a genuine replacement.
A few models of Keihin carb have them, definitely the 350 Four and 400F ones.
I went to a hobby shop and got a piece of brass sheet to make one. Not beautiful and not exactly identical but it works. It just has to push up a little, to defy gravity.
Without a spring the jet's O-ring holds it in but I guess Keihin put that there for a good reason. If the jet and emulsion tube drop out from vibration... that cylinder won't run too well at all.

[Athame57]

You are talking about the 'Leaf Spring'. I broke one recently myself and Honda don't make them anymore. However David Silver from whom I get all my new bits were able to sell me one for just £5.00 they cannibalised from one of the CB400f 's they are breaking. https://www.davidsilverspares.co.uk

[Trevor from Warragul]

PM me your name & address & I'll send you one. Just promise to pay it forward...

[dave500]

use an "E" clip in the jets slot and a coil spring over the jet long enough to contact the carb bowl and itll hold.

[robvangulik]

use an "E" clip in the jets slot and a coil spring over the jet long enough to contact the carb bowl and itll hold.

Good solution to get home (holiday/long way from home) but any steel object will rust quite easily in that hostile environment, and on the long run a coil spring will cause trouble in the floatbowl!

[dave500]

the factory leaf spring is #$%*ing steel anyway,you can use stainless e clip and spring,its an old trick itll work forever,the fuel tank is #$%*ing steel,the fuel lines on my car are steel.

[The Lone Builder]

PM me your name & address & I'll send you one. Just promise to pay it forward...

Thank you - very kind. I promise.

I sent you a pm.