YS 91 SR tuning

[Tom Burgess]

Hi All,

My Aurora has around 6 tanks through it now on slightly richer needle settings than the book states.

I want to try and start leaning it out but every time i do it gets really lean within 2-4 clicks. Is this right? The backplate is still really cool to the touch but the motor runs really rough.

Anyone any ideas? I have read mattie-lodge thread on the check valve getting stuck but as I am getting pressure built up in the tank I am unsure wether it is that?

Cheers

Tom

[Steve]

My experience of all YS engines is that they are very sensitive to needle valve adjustments, much more so than OS engines, so yes 2-4 clicks can make a lot of difference.

Follow the instructions, and do each needle in the order that they write. Just about everyone on here who has one of these engines (including me) has found that they run bang on at pretty much spot-on the needle settings given in the destructions.

[HeliNoobie]

I love my YS engine although its the 50 but there is only 2 clicks between rich and lean for me and iv heard this is normal

[Tom Burgess]

Cheers guys, went over my settings and found my mid needle very rich and also my low. have set to defaults and will give it a go at the weekend, cheers