125 float height (again!)

[Icecreamman]

Had to pull and clean my carb. Figured I’d adjust the float. Read somewhere that standard GY6 is ~18mm but that’s too low. Thinking to bump it up to ~16 or just eyeball it but does anyone know the right float height?

[sc00ter]

From the service manual:

[sc00ter]

You'll have to translate that via a online conversion calculator.

[DeeDee]

I do it by eye. Turn the float upside down and get the dowel to balance on the metal tab. You want to see about 1/32" on each side. Gently bend the tab to reach this. To confirm, place a piece of hose on the fuel inlet, float on the left. Blow through the hose and slowly rotate the carb until the float needle stops air. The float seam should be vertical w/ the carb bowl edge at about 12:45 as shown in the photo.

[DeeDee]

Also, why adjust your float level in the first place? Unless someone has screwed with it, these rarely need touched.

[DeeDee]

Change the bowl screws to allen head.

[Icecreamman]

Thx! Mine doesn’t have that. Tells me how to check it but that’s all. I’ve gotta pull it back off so I’ll double check myself but I’m pretty sure I set it ~18 and it starves when I get on it. Will report on progress.

From the service manual:20241102_143159.jpg

[Icecreamman]

I was in there and I’m just kinda like that.

Also, why adjust your float level in the first place? Unless someone has screwed with it, these rarely need touched.

[Icecreamman]

Got an 08 150 if it matters. My manual says measure perpendicular to the main jet. I’ve got 17.5. Eyeball says ~15. Will report progress.

Thx! Mine doesn’t have that. Tells me how to check it but that’s all. I’ve gotta pull it back off so I’ll double check myself but I’m pretty sure I set it ~18 and it starves when I get on it. Will report on progress.

From the service manual:20241102_143159.jpg

[Icecreamman]

15’s a little wet but maybe I can lean my mix some and make it work. 16’s probably about right. 18’s definitely too dry.

Got an 08 150 if it matters. My manual says measure perpendicular to the main jet. I’ve got 17.5. Eyeball says ~15. Will report progress.

Thx! Mine doesn’t have that. Tells me how to check it but that’s all. I’ve gotta pull it back off so I’ll double check myself but I’m pretty sure I set it ~18 and it starves when I get on it. Will report on progress.

From the service manual:20241102_143159.jpg

[DeeDee]

Messing with your air/fuel screw has nothing to do with this. That is air fuel ratio at idle, float height is about how much fuel fills the bowl how often. You're starving because the flow of fuel stops to the bowl before it is full. Maybe go in and turn the valve adjustment nuts a little for the hell of it.

[Icecreamman]

IDK. I’m upjetted so maybe that’s affecting things. Currently I’m running ~16mm and ~1 3/4 turns and it’s reasonably content.

Messing with your air/fuel screw has nothing to do with this. That is air fuel ratio at idle, float height is about how much fuel fills the bowl how often. You're starving because the flow of fuel stops to the bowl before it is full. Maybe go in and turn the valve adjustment nuts a little for the hell of it.