The Star-Tuner MK-2*, affectionately known as the 'Boo-Hoo', is a simple-to-use, in-house-produced tool for setting and tuning the low-jet needle on the Walbro WB carburettor.
It was initially designed in 2012 in a simpler form to meet the needs for tuning the Vittorazi Moster Classic engines in our workshop. After some persuasion and a rethink, we have made it available to other Walbro WB carb users. It is designed to stay permanently connected to the carburettor, allowing for adjustments on the go.
It accurately allows you to set the low jet to the factory standard state of tune by the recommended minutes of turns out from the closed position. It also provides a way of checking the current state of tune by measuring the turns back in. There are times when the carburettor needs the slightest adjustment before flight (bogging or constant priming to keep running), and this tool allows you to achieve this on the field easily, quickly and confidently with a visual datum of movement.
The tool has a 360-degree turntable head with 1-minute markings around its edge. Four black cardinal points (15-minute spacings) are referenced against the head, which is held in position with the high jet post.
The tool is designed to be permanently left on, secured by a screw clamp and a 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 fitting results. Some WB carbs have a T-bar high jet (Moster Factory). The bar (roll pin) will need to be removed from the high jet if fitting the Star-Tuner.
Due to past issues with customs and lost parcels, we do not ship outside the UK unless you have a contact in the UK who can forward it to you.
Below are the Vittorazi low jets settings for their modified WB carburettor; for up-to-date information, please refer to the Vittorazi User Manual and Maintenance Manual, which can be found on their website.
Atom = 22mins out
Moster Silent/Plus = 15mins out
Moster Factory R = 32mins out
Moster Classic = 15-20 mins out
Fly Easy/Evo = 15-20 mins out
When removing the tool, do so without wiggling or creating a side load on the internal blade. Doing so will damage the tool, rendering it useless and preventing it from being fixed due to the assembly process.
* MK-2 Updated version, stainless steel internal blade and a screw clamp fixing.
Also, consider our Walbro High Jet Tuning Tool for accurate setting of the high-jet.
Walbro carburettor is for illustration purposes only.