50:1 vs manufacturer recommended mixture

I have a 1978 motobecane 50v almost ready to fire up after who knows how long sitting in the garage. It is in excellent condition. The owners manual says to use 32:1 but I'm tempted to use 50:1. Is this dangerous? And why do some mopeds supposedly require a different mixture?

Re: 50:1 vs manufacturer recommended mixture

I would use 40:1. There has been a major improvement in 2-stroke oil since '78. I have a Solex, and run it on 40:1, and it does fine. 32:1 really won't hurt much of anything, it will foul the plug sooner, make more smoke, and plug up the exhaust faster.But these things don't happen overnight, so it won't hurt to try it. Peace. Jerry.

Re: 50:1 vs manufacturer recommended mixture

go with 32:1, things made back then need more lubrication, at our shop stuff thats really old and says 32:1 on it we still use 32:1 on it. And it won't smoke extra and all that crap if it was designed for 32:1, it will run normally. 50:1 is generally only for pretty high performance 2 cycle engines (including new mopeds). Poulan 2 cycle engines and homelites still use 32:1 most of the time. Just goes to show, things haven't changed too much.

Re: 50:1 vs manufacturer recommended mixture

My motobecane SP50 from 1965 was the high performance top of the line model. It was fast. Like 40+ in the flats. The manufacturer reccomended oil ratio was 8oz of oil per gallon. This was before there was special oil for two strokes. Motobecanes from te seventies had almost the same engine, but used 4oz of oil per gallon. The oil got better, a little.

The engine isn't important, it's the oil that makes the difference. If you use a high quality synthetic oil, which you ought to, feel free to run 50:1 without a care. If you want to run lawn mower oil, i would mix it a bit richer.

Re: 50:1 vs manufacturer recommended mixture

My bike was made in 1982 and the manual says 25:1. So I did 25:1 for a while. But it made the old girl fourstroke like crazy.

I leaned out the mix to between 32:1 and 40:1 and now it runs great.

I would recommend running it leaner.

Re: 50:1 vs manufacturer recommended mixture

Patrick Stover /

i run 50:1 on all of my peds, a '78 maxi, '78 swinger2 and a '78 Tomos A3S. All of them run great consistantly with that mixture. I am using Penzoil Premium 2-stroke oil.

Re: 50:1 vs manufacturer recommended mixture

If it hasn't been started in a few years i'lld go with more oil than the manufactures recomendation for the first half a tank to get things good and lubbed up.

Then go with what is recomended by the manufacturer if you have over lube problems you can reduce. If you go to lean from the start you need a rebuild at best and a new engine at worst.Jim

Re: 50:1 vs manufacturer recommended mixture

i would agree with bret on this one, the oil makes the difference. My buddies that run go-karts are so confident in Redline and the purple stuff, they will run 50:1 in karts running at 11k revs. I dont think a single one would run regular two stroke oil (outboard or garden equipment grade) for a hundred bucks. I dont think its going to hurt you to run 32:1 with outboard or weedeater stuff, but if you run better oil you can lean it out, which makes your plugs last longer and pipe stay cleaner.

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