mvvs fuel
 

could anyone advise me on what fuel mixture to use with my mvvs 91 two stroke as i have been told they do not like nitro or castor.

Fuel
 

I've been using 5% Powermaster that is 18% oil (synthetic/castor blend). Have also used FAI fuel (no nitro/ 20% castor oil) with good results. Mine is a .77 with mini tuned pipe.

mvvs fuel
 

frosty46
From size 40 and upwards, MVVS engines are 'timed' to operate on straight fuel - but ought to be able to operate fairly well on up to 5% nitro.

When the engine is new, use a 20% oil content and not much less than this when run-in. A castor content is OK - I use 14% synthetic and 4% castor, for example. Others use a lot more castor content and seem happy with it.

No doubt there are other views out there as well.

MVVS
 

Frosty,

Just don't use any more than 5% nitro, or you will be cursing yourself. If your LHS doesn't stock it, drive further away, or order in some 5%, or FAI.

About the oil; although MVVS specify 20% Castor oil (no synthetic), The Morris Hobbies web site says you can use synthetic oils.
Some prominent RCU members, affiliated with MVVS said the Motul Micro and Graupner Aerosynth II synthetic oils, can be used in percentages of 15.

I still run 20% total oil in my MVVS engines. For safety I suggest some Castor oil should always be (at least 3%).

Sincerely,