Quick fuel mixture Q

I have two of the new rage little pocket bikes and have a question
about the fuel to oil mixture. The manual says to mix the oil 25-1
after the break-in period. However, when i have this mixture, plumes
of smoke come out of the exause and the engine dies (from lack of fuel
im guessing). But, when i mixed the ratio closer to 50-1, the engines
run fine, why is this. Could the manual be wrong? Any suggestions
would be greatly apreciated. I just dont want two hunks of aluminum
sitting in my garage because i blew the engines.
Thanks,
-Zach

 

All depends on what oil you are running. 25:1 is way too much for most
synthetic or semi-synthetic oils 40-50:1 might be a better mix

 

Two-strokes have always been peaked and sometimes temperamental. Long ago,
Mercury Marine introduced an oil called Formula 50-D, because it had to be
mixed at 1 to 50 ratio, while -to the best I recall- outboard technology had
not changed between two model years but, contrarily to a bike, an outboard
always functions with open throttle and is always fed with some oil, which
is not the case with a bike which has frequent/long throttle-off periods. It
must be true that oil formulation will strongly affect lubrication and wear,
but the fact it is synthetic or not does not seem to have as effect as
viscosity, fluidity and other measurable physical characteristics would.
Synthetic is no synonymous of panacea, and "plumes of smoke" would certainly
not be more important with synthetic than conventional (rather contrary I
guess), but indicate too much oil, or a viscosity/fluidity inadequacy.
Could the manual be wrong? depends on who wrote it. If it's the importer of
a motor made somewhere in China and marketed under a variety of brands
sounding sometimes U.S. or German or else, your guess is as good as mine. If
it's directly written by a genuine manufacturer, there should be an
indication of recommended brands (they all do it, between warnings written
by their legal counsels...). But, yes, in some cases, it could be wrong.
Playing with inferior ratio is something I would not try without guidance
from the engine or/and lubricant manufacturers. Assuming you don't get a
response from manufacturer, the best course of action seems to be locate an
oil used by two-strokers (guys racing historic two-strokes for example) and
ask that particular manufacturer for recommendations. Then stick to it. I
have ridden a rented two-stroke historic Benelli, whose owner had developed
a whole chart for determining exaactly how much % to use in hot or wet or
dry weather, etc.
Trying to solve it by using synthetic (which one?) in smaller quantity seems
like applying two medecines at one same time, so you can't tell what is
cause of which. What looks like a good approach would be determine with how
much conventional oil your engines run well, then switch to synthetic and
check how you could safely decrease ratio for more energetic fuel. Then play
with needles etc.
Good luck