clone idle air screw

[Jbrowne479]

i installed a 16hp duromax in my G9 and I have been tweaking on the jetting, i added a bigger pilot jet and an adjustable main jet kit, but i noticed the idle air screw does not have a head on it. how do i remove this to install an adjustable one? I tried grinding a slot in it with my cut off wheel, but as soon as i tried to turn it, a chunk broke off the brass screw... is it epoxied in or something?

[superpro56]

Yes its epoxied. Some have had luck by completely disassembling the carb and heating it to loosen the epoxy. You may be able to spot heat near the screw with the right tools.

Some with machinist skills and specialty tools have been able to center drill and remove the screw. Less DIY friendly than the first method.

Carbs are cheap, so if you mess one up its not the end of the world.

[raydhd]

ARC racing sells an original Honda carb that merely has a limiter cap on that screw that is not to difficult to modify. A couple of members here have done this. The part # is DJ-3225 and it is like $40

[raydhd]

Originally Posted by Jbrowne479

i installed a 16hp duromax in my G9 and I have been tweaking on the jetting, i added a bigger pilot jet and an adjustable main jet kit, but i noticed the idle air screw does not have a head on it. how do i remove this to install an adjustable one? I tried grinding a slot in it with my cut off wheel, but as soon as i tried to turn it, a chunk broke off the brass screw... is it epoxied in or something?

I was the poster boy for how to try and ruin a carb. I started it by doing exactly what you tried. Luckily Shepard save mine and showed how he did it which I just bumped up

[Jbrowne479]

thank you for the replies

so is it worth buying the honda 2 circuit carb or should i just pony up for a three circuit?

if three circuit is a good route, which one should i buy?

thoughts of going to a china flat slide crossed my mind as well, but how do you make the throttle cable work?

[raydhd]

The 3 circuit also has the epoxy idle screw.As far as I know VC is the only one selling the 3 circuit carb. Buying the Honda carb is the simplest route. The cycle carbs are going to require some rejetting along with linkage space in a yamaha is challenging. This area as in so many others how much work are you willing to do ? And what is your end goal ?

[Jbrowne479]

I was thinkin going to the cycle carb because I've had way more experience tuning them over the years. kinda liking the ease of bolt on with the honda carb though. I'm thinkin I need to add a return line to my fuel pump as well, seems like the cart is super fat on the bottom (hence the wanting to make the idle air screw adjustable)

[superpro56]

Originally Posted by Jbrowne479

I'm thinkin I need to add a return line to my fuel pump as well, seems like the cart is super fat on the bottom (hence the wanting to make the idle air screw adjustable)

Had to do that with my VC625. The pump was overwhelming the needle and seat in the carb so much so that the float bowl was overflowing and leaking raw fuel into the engine compartment. Installed a return line and completely took care of the issue, left the idle air screw stock and just used the adjustable main jet to tune high end.