Carburator pop-off hw-27a

Hi. I want to deacrease the pop off how do i do it

Either a lighter spring, for example 27g instead of 37g, or cut/compress the existing spring to make it shorter. First option is preferred.

Where is the spring your refering to located.
Is it part number 3379 on this picture?

No, it’s 3026

Here is a good overview of what’s happening with the carb.

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Skip to around 6 or 7 minutes in this video. I recommend watching the whole thing when you can.

So its heavyer spring less popp off for exaple if i have a 26g spring and i have like 2bar and i put a 30 i will have 1.5 bar ??

The opposite, the lighter the spring the less force is required to "pop off’ the needle from the seat as there is less pressure applied. I don’t have that specific carb, but in others, I have accomplished a lower pop-off by removing loops from the spring, shortening the spring reduces the force the spring is applying thus reducing the pop-off pressure.

How do i know what spring i have rn

If there is a kit with an array, you can test the Popoff with a known weight spring, determine if the spring was stronger or weaker than the current spring, and evaluate from there.

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Thanks for the help everybody


How often do i change theese

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Needles shouldn’t need to be changed. Clean them and reassemble.
It doesn’t look like you have O-rings on them though, so they will leak air/fuel. O-rings, change as required.

I have o rings but i left them inside beacuse i just rebuild it