Ayesully810 Posted June 14, 2016 Author Report Share Posted June 14, 2016 are you using fresh fuel, same fuel octane, same pre-mix oil and pre-mix ratio? Yes sir, he ran it with 93. I drained all the old gas that was out of it and put new gas in it.. The previous owner was running it 32:1 and the plugs looked pretty dark so I ran it 40:1 and the plugs are still looking the same. Im gunna have to wait and post pics of the plugs later tonight or in the morning. Quote Link to comment Share on other sites More sharing options...
Strm Trpr Posted June 14, 2016 Report Share Posted June 14, 2016 Running your pre-mix 40:1 vs 32:1 is enough to require rejetting. Now the pre-mix has more fuel ppm and less oil ppm. The motor is now running richer even though your pre-mix is lean, fuel-oil ratio wise... Quote Link to comment Share on other sites More sharing options...
Ayesully810 Posted June 14, 2016 Author Report Share Posted June 14, 2016 Running your pre-mix 40:1 vs 32:1 is enough to require rejetting. Now the pre-mix has more fuel ppm and less oil ppm. The motor is now running richer even though your pre-mix is lean, fuel-oil ratio wise... Can you help me understand a little better how that would require rejetting please. So does that mean that the more oil I put in the premix, the motor is going to run more lean? That sounds backwards to me, but I am limited in knowledge so thats why I posted here. Quote Link to comment Share on other sites More sharing options...
Strm Trpr Posted June 15, 2016 Report Share Posted June 15, 2016 Can you help me understand a little better how that would require rejetting please. So does that mean that the more oil I put in the premix, the motor is going to run more lean? That sounds backwards to me, but I am limited in knowledge so thats why I posted here. OK, let me try to explain this. 5 gallons of fuel is 640 ounces. 32:1 pre-mix you need to add 20 ounces of oil to 5 gallons of fuel. << 660 ounces of pre-mix. In a specific volume of 32:1 pre-mix you will have less parts per million of gasoline and more parts per million of oil. Now shoot 32:1 pre-mixed fuel thru your carb mixed with a fixed volume of air. The 32:1 pre-mixed fuel has less actual combustible gasoline and is now mixing with a fixed volume of air flowing thru your carb into your motor. The air/fuel mixture has less fuel for a fixed volume of air and is now actually leaner. 40:1 pre-mix you need to add 16 ounces of oil to 5 gallons of fuel. << 656 ounces of pre-mix. In a specific volume of 40:1 pre-mix you will have more parts per million of gasoline and less parts per million of oil. Now shoot 40:1 pre-mixed fuel thru your carb mixed with a fixed volume of air. The 40:1 pre-mixed fuel has more actual combustible gasoline and is now mixing with a fixed volume of air flowing thru your carb into your motor. The air/fuel mixture has more fuel for a fixed volume of air and is now actually richer. Your motor is jetted for 32:1 pre-mix. Now you've now added more fuel to your pre-mix by pre-mixing 40:1. << more ppm of fuel to oil ppm. Your jets are too large and your motor is running rich and having a hard time getting on the pipe. Try this, turn your airscrews out 1/2 a turn and raise the clip on your needle up 1 groove and report back. By turning your airscrews out 1/2 a turn you've added more air to your idle circuit. By raising the clip up 1 groove you've actually lowered the needle into the needle jet and leaned out the mid-range. I bet it'll stay idling longer and it'll get on the pipe harder. I hope that makes sense... 1 Quote Link to comment Share on other sites More sharing options...
Ayesully810 Posted June 15, 2016 Author Report Share Posted June 15, 2016 OK, let me try to explain this. 5 gallons of fuel is 640 ounces. 32:1 pre-mix you need to add 20 ounces of oil to 5 gallons of fuel. << 660 ounces of pre-mix. In a specific volume of 32:1 pre-mix you will have less parts per million of gasoline and more parts per million of oil. Now shoot 32:1 pre-mixed fuel thru your carb mixed with a fixed volume of air. The 32:1 pre-mixed fuel has less actual combustible gasoline and is now mixing with a fixed volume of air flowing thru your carb into your motor. The air/fuel mixture has less fuel for a fixed volume of air and is now actually leaner. 40:1 pre-mix you need to add 16 ounces of oil to 5 gallons of fuel. << 656 ounces of pre-mix. In a specific volume of 40:1 pre-mix you will have more parts per million of gasoline and less parts per million of oil. Now shoot 40:1 pre-mixed fuel thru your carb mixed with a fixed volume of air. The 40:1 pre-mixed fuel has more actual combustible gasoline and is now mixing with a fixed volume of air flowing thru your carb into your motor. The air/fuel mixture has more fuel for a fixed volume of air and is now actually richer. Your motor is jetted for 32:1 pre-mix. Now you've now added more fuel to your pre-mix by pre-mixing 40:1. << more ppm of fuel to oil ppm. Your jets are too large and your motor is running rich and having a hard time getting on the pipe. Try this, turn your airscrews out 1/2 a turn and raise the clip on your needle up 1 groove and report back. By turning your airscrews out 1/2 a turn you've added more air to your idle circuit. By raising the clip up 1 groove you've actually lowered the needle into the needle jet and leaned out the mid-range. I bet it'll stay idling longer and it'll get on the pipe harder. I hope that makes sense... Okay that makes more sense. Thank you for explaining. So basically if this is actually what my problem is coming from, sounds to me like I just wasted 5 gallons of gas and should have just kept it at 32:1 like a good boy Quote Link to comment Share on other sites More sharing options...
Strm Trpr Posted June 15, 2016 Report Share Posted June 15, 2016 Or you can try what I suggested with your airscrews and needle clip position to see if my theory about you changing your pre-mix is valid. Quote Link to comment Share on other sites More sharing options...
Ayesully810 Posted June 15, 2016 Author Report Share Posted June 15, 2016 Or you can try what I suggested with your airscrews and needle clip position to see if my theory about you changing your pre-mix is valid. That too, sorry didnt mean to leave that out, was not dismissing what you suggested, much appreciated. Ill be back with updates within the next day Quote Link to comment Share on other sites More sharing options...
sheerider11 Posted June 15, 2016 Report Share Posted June 15, 2016 32:1 and 40:1 are so close you don't need to rejet. I've run both. Never noticed an issue. 1 Quote Link to comment Share on other sites More sharing options...
Strm Trpr Posted June 15, 2016 Report Share Posted June 15, 2016 32:1 and 40:1 are so close you don't need to rejet. I've run both. Never noticed an issue. Well, guess I'm wrong then. Quote Link to comment Share on other sites More sharing options...
sheerider11 Posted June 15, 2016 Report Share Posted June 15, 2016 Well, guess I'm wrong then.There really just so close to each other that you don't need to rejet. When I mix in my ratio rite I'm not always dead on the line. I'm over or under. I've gone 40:1 on rides where I started to get low on oil. Sent from my SAMSUNG-SM-G890A using Tapatalk Quote Link to comment Share on other sites More sharing options...
Strm Trpr Posted June 15, 2016 Report Share Posted June 15, 2016 There really just so close to each other that you don't need to rejet. When I mix in my ratio rite I'm not always dead on the line. I'm over or under. I've gone 40:1 on rides where I started to get low on oil. Sent from my SAMSUNG-SM-G890A using Tapatalk Maybe if he was jetted fat with his 32:1 and then switched to 40:1 that might be enough to need rejetting, but maybe not.It would be interesting to see if a 1/2 turn out on the airscrews and lowering the needle cleared it up though. I drop a pint of Yamalube 2R into my 5 gallon jug and that's that. No ratio rite needed. Been doing so for 20+yrs without a failure, knock wood... Quote Link to comment Share on other sites More sharing options...
Strm Trpr Posted June 15, 2016 Report Share Posted June 15, 2016 This is a good read. http://www.chronicmx.com/dirt-bike-tip-reduce-stroke-spooge/ OP, you might want to also make sure your idle is set correctly and that your carbs are sync'd at both idol and part throttle. 1 Quote Link to comment Share on other sites More sharing options...
Strm Trpr Posted June 15, 2016 Report Share Posted June 15, 2016 OP, read that article. You said yourself that you changed your ratio from 32:1 to 40:1 because your plugs looked black and wet, The oil in the pre-mix isn't what's making your plugs look that way, it's your jetting. Your motor was jetted too rich with 32:1 to begin with and now you've added more fuel by going to 40:1. 1 Quote Link to comment Share on other sites More sharing options...
Ayesully810 Posted June 15, 2016 Author Report Share Posted June 15, 2016 Chris, my bike is shooting oil out of the back like this article talked about.. Infact yesterday when i was letting it idle, it left a bird shot of oil on the ground and the back of my swing arm after revving it a few times. Quote Link to comment Share on other sites More sharing options...
Ayesully810 Posted June 15, 2016 Author Report Share Posted June 15, 2016 OP, read that article. You said yourself that you changed your ratio from 32:1 to 40:1 because your plugs looked black and wet, The oil in the pre-mix isn't what's making your plugs look that way, it's your jetting. Your motor was jetted too rich with 32:1 to begin with and now you've added more fuel by going to 40:1. e I wanna make sure I rule out everything else though before I start changing things in the carbs like JD and the above article suggested. Quote Link to comment Share on other sites More sharing options...
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