Dell'orto question - non Laverda

[Ernesto]

There are two types of float valves: with and without spring pressure.
How would they affect the function and under which conditions would
you choose which?

Ernesto

 

[3CBRG]

I'm betting the consensus is: go with what came standard with your Dell'orto. If you have PHF'S then no spring. Where's Dellorto Man when you need him?

 

[GregT]

I note it's non Laverda...

Generally, in my experience anyway, the spring loaded float needles are used on applications where hign frequency vibration is expected.
Two strokes in particular.
I'd also point out that across many carb manufacturers, it's very, very rare to find solid float needles now.

 

[Ernesto]

'm betting the consensus is: go with what came standard with your Dell'orto.

Of course I'll go with what I found, in this case no spring on a Guzzi V 35 Imola.
But I wanted to know the story behind it. Thanks to Greg.

 

[chrisk]

Of course I'll go with what I found, in this case no spring

There'd be plenty of bounce in your avatar though.

 

[MarnixSFC]

There are two types of float valves: with and without spring pressure.
How would they affect the function and under which conditions would
you choose which?

Ernesto

In my experience with Laverda and Ducati, the round slide PHB/PHF/PHM have the valve with spring and the square slide VHB has a valve without.

Marnix

 

[Tippie]

I can't remember any without, that is why you have to tilt the carbs when checking float heights, so that the spring is not compressed.