What fuel/oil ratio should I run

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I have the 66 cc chinadoll motor on my bike for my break in I ran 16:1 after 3 tanks of that I run 25:1 I am wondering what I should run and if there’s going to be a performance difference with a different ratio
 

ImpulseRocket89

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I have the 66 cc chinadoll motor on my bike for my break in I ran 16:1 after 3 tanks of that I run 25:1 I am wondering what I should run and if there’s going to be a performance difference with a different ratio
Depends on the oil, the ambiet temps, and if the motor has any modifications such as higher compression. A thinner oil mix will produce less drag on the internal components and the fuel mixture burns faster and cleaner (with some exceptions obviously). This means less oil can help make more power and turn higher rpm.

Most people tend to run 32:1 after break in on most of these engines, but if you push it hard for extended periods of time and/or ride on hot days I would stick to the 25:1 and just run a high quality ashless standard oil (Valvoline and STP) or a good quality synthetic (my personal fave is VP Racing synthetic for small engines)
 

DAMIEN1307

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I have the 66 cc chinadoll motor on my bike for my break in I ran 16:1 after 3 tanks of that I run 25:1 I am wondering what I should run and if there’s going to be a performance difference with a different ratio
Most run of the mill, regular CG motors run quite happily at a 32:1 ratio after breakin is over with...Synthetic 2 cycle oil is a plus and even the Wal-Mart 2 cycle synthetic works quite well...Just be sure that when your mixing your ratio that you use a gas can/jerry jug and not mixing it in the tank as it will be inaccurate plus the fact that you can't shake it well so you have a consistant premix before pouring it into the tank.

32:1 = 4 ounces of oil to one gallon of gas.

EDIT:...Looks like ImplulseRocket man typed faster than I did...lol.
 

Axl Myk

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16:1 is too much to start with. All it does is foul the plug, and coat your shoes with oil.
32:1 is good. 4oz/gal or 125ml/4L
 

Daytripper24699

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Depends on what kind of cylinder you have. If it is an aluminum one like most china dolls run 40:1 and if it is an iron bore or steel sleeved cylinder run 32:1
 

DAMIEN1307

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run 32:1 after break in
CG motors run quite happily at a 32:1 ratio after breakin
32:1 is good. 4oz/gal
Seasoned veteran builders and riders of these MBs pretty much stick with 32:1...NOT 40:1...The oil is the lifeblood with these 2 cycle air cooled motors that are carrying itself and you under load.

We do NOT recommend less oil than a 32:1 mix...You need this oil protection for the motor.
 

Greg58

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This is where you will get all kinds of answers, I have been running my bikes at 32/1 for over 10 years. My first engine is a 2010 Grubee that I have on the bench right now replacing the top end which is the original, I did way too much porting on that cylinder, it ran great but wide ports wear the piston and rings faster. The day before I took it off the bike it turned 8430 rpm.
 

ImpulseRocket89

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Seasoned veteran builders and riders of these MBs pretty much stick with 32:1...NOT 40:1...The oil is the lifeblood with these 2 cycle air cooled motors that are carrying itself and you under load.

We do NOT recommend less oil than a 32:1 mix...You need this oil protection for the motor.
My one exception would be for a high end synthetic oil. I did run 50:1 on my last 66cc engine with Amsoil Dominator without issue, but that stuff is also expensive. Regular Valvoline or STP 2 cycle at 32:1 ends up being a lot cheaper to run and burn very clean.
 
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