I have an asp 21a engine.....  And i bought 4 litres of tornado 16%Nitro methane...  How much percent of Castor oil should I mix so I can run asp 21a safely?

@Rajji : 16% nitro methane is too much for Aeroplane Engine use only 1 to 5% nitro methane. You have brought car Fuel. Nitro car needs 10 to 20% nitro methane Fuel.

I bought some methanol I'll mix it with castor oil and make own fuel.... can u tell me the break in procedure?

i think u don't use caster oil for your asp 21 u can use synthetic oil instead of caster oil break in procedure is called running in u should run your engine attlist 1.5 ltr fuel first runs in rich and low rpm and some early flights also engine should be rich and hobby flying i thing don't think u need nitro methane only 80/20 ratio fuel is enough 80% methanol and 20% caster oil/synthetic oil  enjoy hobby  

okay can u tell me the exact run in procedure
? thanx

Rajji
Where did you buy the engine from? The engine should have come with a set of instructions. Please follow them. What is the application you are intending to put this engine to use?

Go by what Gaurang says.... he is spot on on the advice.....