Premix fuel

[masta-BETA]

Hey there all you two stroke riders, this may sound like a silly question but having to mix my fuel is new to me after riding four strokes for 35yrs. James my dealer has now got me using Motul 800 pre-mix (a bit more pricey at $89 for 2L) instead of the Spectro sx2($103 for 4L) I was using, forgot to ask him is it ok to have 1/2,1/4 or 3/4 a tank of the Spectro sx2 in the bike then fill her up with a mix of the Motul 800 both at 40:1 mix or do I have to run it right down before I fill her up with the new Motul mix. Cheers Richard

[mtdirtbag]

I didn't have any problems changing from Motul to Torco GP7 and I might add I never have had a problem in mixing other ones in the past. I don't know anything about the Spectro, but if it's synthetic there should be no problem.

[flybars]

I'll second that. Doesn't seem to make a difference. I just started using a Amsoil premix and added it to a half tank when of different brand with no ill effects.

[masta-BETA]

I'll second that. Doesn't seem to make a difference. I just started using a Amsoil premix and added it to a half tank when of different brand with no ill effects.

Hey there, yeah didn't really think there'd be an issue, would rather ask the question than go ahead and have something silly happen that I didn't know about. Cheers Richard

[webmaster]

I don't mean to worry you - but I looked up the oil you are using and it is ester based. I recall (although not too clearly! - that ester based oils can sometimes be incompatible with other oil types.

If it were me - I would drain out the old fuel and use it in the lawn mower. Then top her off with the new blend.

jeff

[masta-BETA]

I don't mean to worry you - but I looked up the oil you are using and it is ester based. I recall (although not too clearly! - that ester based oils can sometimes be incompatible with other oil types.

If it were me - I would drain out the old fuel and use it in the lawn mower. Then top her off with the new blend.

jeff

Hey there,thanks for the heads up on the oil being incompatible with others, I will drain what's left in the tank before I fill her up with the new blend, info very much appreciated. Cheers Richard

[flybars]

Good catch Jeff.

[Darkside]

40:1 of motul 800 is pretty rich. If you get a lot of spooge you might want to go leaner or look into switching to 710 which has a lower flash point and burns a bit cleaner

[Enmerdeur]

The oil incompatibility hysteria comes from the days of oil injection on two strokes. There was a problem when mixing different oil types in an injector tank since they were not diluted at all but with premix it is a non-issue.

[GMP]

Also when castor oils were more common.

What can hapen with ester oils is they absorb moisture very easily and can start to separate from the fuel if humidity is high. Not with Motul but happend to me with Redline (ester base) awhile back. I would find unexplained water/oil component droplets in the float bowl and gas can. Sometimes this would even tarnish the carb brass.