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Walbro WB 'Boo-Hoo' Low Jet Setting Tool

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  • Regular price £16.95
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Formerly called the 'Star-Tuner', however, renamed to the 'Boo-Hoo' in recognition of my new friend John.

The 'Boo-Hoo' is a simple in-house designed and produced tool for Walbro WB carburettors. Initially designed in 2012 to meet the needs for tuning the Moster Classic in our workshop.

It accurately allows you to set the low jet to factory standard state of tune by minutes of turns out from the closed position. Also, a way of checking the current state of tune by measuring the tunes back in. There are times when the carburettor needs the slightest adjustment, and this tool allows you to achieve this with a visual datum of movement confidently.

The tool has a 360-degree turntable head with 2-minute markers around its edge (1-minute from peak to trough) which is referenced by four black cardinal points (15-minute spacings), which are held in position (don't turn) by the high jet post. 

Fit the Star-Tuner over the high jet post, align the magnetic blade with the slot of the low jet and press firmly in place. The head of the low jet screw should not be visible due to being inside the brass shaft. Gently close the low jet (clockwise) until seated, use a pencil and mark one of the peaks or troughs against one of the aligned black cardinals. Turn out by the desired amount of minutes. The tool can be left on permanently if it's been passed through its own lanyard for backup. 

You may find that your current low jet has been de-faced if tuned in the past with a screwdriver, and we recommend replacing the low jet with a new one for the best results.

Below are the low jets settings for the WB; please refer to Vittorazi User Manual and Maintenace Manual, which can be found on their website.

Atom = 22mins out

Moster Plus = 15mins out

Moster Silent = 15-20 mins out

Moster Factory R = 32mins out

Fly Easy/Evo = 15-20 mins out

When removing the tool, pull off straight without wiggling or creating a side load on the blade, as this will snap the magnetic blade rendering the tool useless, and it can not be fixed due to the assembly process. 

Also, consider our Walbro High Jet Tuning Tool 

Orders outside of the UK are welcome via email

Walbro carburettor is for illustration purposes only.