Fuel:oil mixture for RM 125 B

[SON]

There is too much mis information re spark plugs even from qualified people
That is why manufacturers have recommendations and tuners stretch their limits

[Sweep Rider]

My RM125A, RM370A, and IT250D all say 20:1..... for a reason. Dyno's have proven that you obtain more power with the higher oil content, it's safer when your tuning and go that bit lean and the biggest advantage is the oil dissipates HEAT out the exhaust.
It's not all about lubrication. Any mineral based oil will be fine.
I just finished the Murphies Creek Vinduro where it was 40 deg + and gnarly hills. I felt better knowing the IT was running 20:1
 

[SON]

Once again mis information
You guys just can't help yourselves
Back in the early 90s I would escape from work every time the Lucky Strike GP Team came to OZ testing
I can't remember them mixing fuel at 20:1 but maybe I am wrong

[John Orchard]

All my bikes, chainsaws & brushcutters use 25:1 Valvolene Mineral racing oil, $9.95 per litre.  125's & 250's use B9ES, 400 uses B8ES.

The bikes are fast & reliable, never any noticeable wear anytime I tear them down.  Main reason's I use this oil is good plug colour for tuning and it's available at many local shops.

Works for me.

[JohnnyO]

You guys are living in the past with your 20:1 and mineral oils. Your Suzuki manual that recommends 20:1 was printed in 1977 based on the oils that were available back then.
Modern oils have improved out of sight since 1977 and today's bikes make a lot more horsepower and rev a lot harder and the manufacturers use and recommend 40 or 50:1 and there are far less engine failures today using that mix than back in the day.

[FourstrokeForever]

You guys are living in the past with your 20:1 and mineral oils. Your Suzuki manual that recommends 20:1 was printed in 1977 based on the oils that were available back then.
Modern oils have improved out of sight since 1977 and today's bikes make a lot more horsepower and rev a lot harder and the manufacturers use and recommend 40 or 50:1 and there are far less engine failures today using that mix than back in the day.

AGREE 100%

[davidmc]

FYI; We always ran HRC NSR500 on Castrol A747 at 28 to 1 , that was the safe limit;
You may get away with leaner oil mixs , But if you are recommending from a reliability point of view that will cover all situations.

[Rossvickicampbell]

JO - I agree with you but have a question - as the years marched on and 2 stroke mixtures got leaner - how much do you think this was driven by the enviromental movement and oil smoke pollution?  At all - I just hear rumours of the return of the 2 stroke at oil rations of 100:1 being environmentally acceptable?

[davidmc]

1981 Maico 490 manual recommends;
special high Quality oil mixture,

1;20 with 2 stroke oil
1;50 with Bel Ray MC1
1;100 with Maico MC-GP-100 Mix oil
and cautions never to mix Mineral and Synthetical oils.

Keep in mind a 490 does not rev as high as a 125cc
Maico oil must have been special stuff taken from either whales or vestal virgins.

[Ktm181]

1981 Maico 490 manual recommends;
special high Quality oil mixture,

1;20 with 2 stroke oil
1;50 with Bel Ray MC1
1;100 with Maico MC-GP-100 Mix oil
and cautions never to mix Mineral and Synthetical oils.

Keep in mind a 490 does not rev as high as a 125cc
Maico oil must have been special stuff taken from either whales or vestal virgins.

Best talk to GB about running a 490 at 100:1.... i wouldnt, Geoff's nipped up,cant remember the brand of oil though.
 I dont understand a discussion like this, or some others appearing on here, its pretty obvious there are lots of ways to skin a cat, lots of oil ratios "will work", some produce better performance, some produce less wear, its not rocket science. Its smarter, if using plain mineral to run it on the cautious side with more rather than less oil, if your running the super duper stuff then you might be happy with lesser amounts, you just need to remember the oil and its film strenght is all thats keeping your engine alive, NONE of this is meant to be an argument you HAVE to win.
I reckon some of you gentlemen need to re focus and remember to enjoy your "sport" a bit more, its not meant to be taken too seriously after all.

Kt.

[SON]

FYI; We always ran HRC NSR500 on Castrol A747 at 28 to 1 , that was the safe limit;
You may get away with leaner oil mixs , But if you are recommending from a reliability point of view that will cover all situations.

Dave I thought it was 32:1 at HRC
I remember Schwantz RGV500 with Motul at 40:1
I have used that ever since NEVER had a hint of a problem
Old bike or new
Remember Unleaded Modern Fuel v Leaded Old Fuel

[Ted]

v Shell URT

[davidmc]

As I remember it was 28:1,  as big ends tend to let go any less oil mix, you can get away with a leaner mix in most cases on the dirt where you are on and off the throttle, and of course 500 singles don,t run high RPM,
but I wouldn,t like to run my aircooled 125 flat out in sand at 50;1,
and after all this was about a question of recommendation??

[Ted]

Which it was answered in the very first post and which he has subsequently done

[80-85 husky]

it is good to have a huuuuge far ranging discussion though, interesting to see what people do and what the results are...

watching some vinduro clips, its easy to see who is still 20: to 1 and who isn't (or who forgot the oil completely!!!)

I like hearing what the high level guys did then and now as they tend to have the best intelligence (or sponsers)

As for running a 125 in sand at 50: 1.. absolutely no problems AS LONG AS YOU JET IT RIGHT!

any desert riding I have done I always drop the needle 1 clip and take a few bigger main jets. ( I always tread carefully for the first few k's to listen for that noise!! )

I fear the midrange seizure on throttle close in sand more than any other potential malfunction as it tends to be without warning.

Hopefully it rains soon and we can stop typing and go riding.....