Velocity stacks / Air filters

[El__burro]

I reckon that the poor running (and even at idle) of the engine could be caused by the lack of air filters.
I have removed it and just kept the cones that look like velocity stacks.
Today I have covered them with a t shirt cutting and at times i felt like it improved the idling.
I don't want to reinstall the old filter box but I am not sure if this solution could work somehow.
Shall I opt for velocity stack or a set of these spongy filters?
Thanks
El__burro

[haynes66]

i think it looks fine as it is!!

[mike the bike]

Nothing wrong with T shirt filters, go for it.

[Spitfire]

Now that is inventive, would never have thought of that one.

Cheers

Dennis

[El__burro]

My mixture screw is all closed. How many turns should it be set to?

Thanks
El__burro

[Bryanj]

varies by exact model of bike and carb

[El__burro]

It's a cb750 k2 with stock carb (no airbox). Surely all closed is not right is it?

[Johnwebley]

my thoughts are tee shirt cloth is to restrictive,

 I would experiment with tights,

 maybe one or two layers,
not the thick woolly ones !!!!

see this link
http://www.speedwaybikes.com/handbook/sh_ch10.htm

[Bryanj]

All closed is not correct, try about 2 1/8 turns out for a start

[El__burro]

thanks,
that is a nice read.
Panty hose or nylon stocking is the way to go..
over the filter I mean.
Actually the screw that is all tight, is the throttle stop (according to the diagram) the one in copper visible in the picture.

I need to find the air mix screw and work out different settings.

thanks
el__burro

[Spitfire]

These might help



Cheers

Dennis

[El__burro]

thanks Dennis,
actually the problem of poor idling is caused by fuel and not filter or air starvation.
when I feed the 2 sets of carbs individually it roars like a lion.
Probably there is a blockage in the connections between the carbs caused by the "rubbish" i found in the tank.
Is there an easy fix that doesn't require carbs removal?

Thanks
el__burro

[El__burro]

I've removed the carbs just to figure out that there is no direct connection between 1-2 and 3-4.
My question is, how do I feed all the carbs at once.
I have one fuel pipe feeding 1-2 and the other 3-4
how this works exactly

thanks
el__burro

[Spitfire]

This shows the fuel lines on my CB750F1, hope it helps, here's a thread on the same subject. http://forums.sohc4.net/index.php/topic,76367.0.html


Cheers

Dennis

[El__burro]

maybe I need to connect each fuel pipe to both carbs.
correct?