RE: Saito 125 Fuel Mix
My Saito 1.25 manual does not suggest 10-20% nitro or fuel without castor.
What it does say is 20% oil and 10-15% nitro is recommended. If not available, then high quality 2 stroke glow fuel such as Hangar 9 Aero Blend, Omega, Cool Power, K&B, Power Master, etc.
Using fuel with entirely castro is not recommended.
A mix of synthetic and castor is acceptable.