yamaha 50-1 or 100-1 mix

G

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Can anyone please help,
I have recently aquired a late 80'S 60hp yamaha outboard. As it has not run for some months, I used a 50-1
petrol oil mix but have been told that this engine runs on 100-1. Is this right!.
Thanks russ.

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pete

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Hi
I have a Yamaha 15 and a Yamaha 4 and both are labled (on the engine cover) 100/1 but I have read that this may leave no margin for error so I tend to use 50/1 and feel a bit safer, I have had them both for a few years now with no probs.
Pete

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muchy_

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I ran my old Yamaha 20 on 50/1 and had lots of smoke and running problems. Then found out that it should be 100/1 and it ran a hell of a lot better. But then that was for river use so didn't get a good thrashing very often so it used to oil up.

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snowleopard

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my dealer said that the 100:1 was to meet pollution standards. the engines will run on it but it's not very good for them. i use 100:1 but always pour a bit extra so it's probably more like 75:1.

my garden tools still run on 25:1 and i recall seagull specifying 12:1

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G

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Thanks for all your help guys,
as long as I know that running it on 100-1 wont kill it, I'll probably play safe and use 75-1 mix.
Its just that it seems a little bit smokey on start up and the plugs oil up a bit.
thank again
russ

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Heckler

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just to chuck a spanner

in the works, 100-1 is the official mix.
when we used to go racing motor cycles the mixing of the two stroke was crucial and some friends of mine who were racing yamaha twins told me about the " oh we always add a bit to be safe " brigade, they were always holing pistons, turned out that by "adding a bit more oil" it altered the octane rating and made the engine "pink" or detonate and this holed the pistons, so the moral of the story is always go by the manufacturers recommendations !!
stu

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Boathook

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We used to have a 28hp Yamaha that ran on 100:1 Due to the cruising at less than half revs the plugs oiled up. We changed to hotter plugs that cured the problem, but were told not to use full revs for long periods. This all worked very well and main dealers used the same spec plugs when they serviced it.

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