100 to 1 Oil Mixture Ratio

I picked up my new 25 HP Yamaha ELH yesterday, and the dealer said to use 50 to 1 for the first tank, then use 100 to 1. I see most people use the 50 to one. Which is better?

Check your manual. The brand new 2009 15 hp Yamaha I purchased last year states 25 to 1 for the first ten hours.

yes the manual does say 50 to 1, then 100 to 1..

i just got a new yami 15,its 100:1

I have a 2008 Yamaha 25-hp 2-stroke motor and the manual says to run it at 25:1 for the first ten hours and then at 100:1 after that. Despite what the manual says, I run it at 50:1 after break in.

I just took a look at the owner's manual for your motor and, yes, it says 50:1 at break in while my 2008 25-hp Yamaha says to use 25:1 at break in. I wonder why the difference?

I have a 4HP Evinrude from the 80's that calls for 100:1 but I always run 50:1 in it. Seems to run better like that. Maybe after you break it in you could exeriment to see what mixture runs best.

Alot of outboards say 100:1 but most poeple run 50:1.
I go alittle lighter when I know I'm going to run my outoard everyday,most times 50:1 though.
Question you could ask yourself:
What's worse fouled plugs(sometimes) or blown motor(a maybe also)?
I know what side I'd lean to.

I have a 86 Suzuki 8hp and it's 100/1 and it has been 75/1 after break in form brand new and still runs great

Zum said:

Alot of outboards say 100:1 but most poeple run 50:1.
I go alittle lighter when I know I'm going to run my outoard everyday,most times 50:1 though.
Question you could ask yourself:
What's worse fouled plugs(sometimes) or blown motor(a maybe also)?
I know what side I'd lean to.

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Excellent advice ZUM. Set of spark plugs every couple of years = couple of buck$, but a burned up power head = couple of grand$$$$$$$

Just saying

My Yammy dealer suggested 80:1 after break-in instead of 100:1 just to add a little additional lube. I'll probably do that since it's better than 100:1 but doesn't burt as much oils as 50:1.

Oh, and my 2008 25ESH suggested 50:1 during break-in. Check your manual and follow what it says.

my 15 smokes pretty good at 100:1. is this normal for a 2011 motor? it's a 3 month old trade in so it was probably broken in.

bcbouy said:

my 15 smokes pretty good at 100:1. is this normal for a 2011 motor? it's a 3 month old trade in so it was probably broken in.

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When it idles or all the time?
I can't see 100:1 smoking all that much but I've only used 50:1 so hard to say.
Have you used other outboards;at 50:1 to tell the difference?
Did you use a higher ratio when breaking it in?maybe still some residue oil in there.

Sure your using the right amount of oil?
It would only be 200ml in 20 liters of gas.(metric system makes it easy)400ml at 50:1.

250 ml of yami lube semi synthetic for a 25 l tank. it was 3 months used when i got it. smokes alot at idle. my 9.9 johnny smokes a little less at idle, 50:1, when the pos decides to run.

Deadmeat said:

I just took a look at the owner's manual for your motor and, yes, it says 50:1 at break in while my 2008 25-hp Yamaha says to use 25:1 at break in. I wonder why the difference?

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dont know..