I changed my premix from 32:1 to 40:1 bc it was running real rich and ever since it has started missing once i get on the throttle and opening it up i just put a new plug it i don't know what's wrong with it if anyone can help me that'd be great.
Blaster is missing running weird
- Thread starter 2000yamaha
- Start date
Did you change the jets to accomodate for a different fuel oil mixture? I dont think changing it that little would do this.
Changing the fuel to oil ratio won't fix anything.
Start with...
#1...Checking the plug
#2...Cleaning the carb
Start with...
#1...Checking the plug
#2...Cleaning the carb
By changing the oil ratio to 40:1 you made it run about half a main jet richer. You went from running rich, to running richer because of the extra gas in the mix.
What you need to do is find out what is making it run rich, is it because the temp has warmed up, is the needle and seat dirty allowing uncontrolled fuel into the carb?
If you tried to fix the rich condition by using less oil in the premix, then you went the wrong way, you have to add more oil to produce a leaner mix!
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^^ agreed, its a common misconception that less oil in the fuel means a leaner mix where the exact opposite is true
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When you still have to figure out why it was running rich. Dirty filter, float height, wrong jet?
I changed from 32:1 to 40:1 be it was running real rich and oil was coming out the exhaust i could out my hand behind it and rev it was i would have a little oil on my hand but it ran great a 32:1 im at 40:1 now i think im going back to see if that would be the problem bc it started doing this missing the first ride i took mixed 40:1.
oil comes out of my exhaust also, its normal, just leave it at 32:1 if it ran great
The problem lies not in the oil ratio, but in the jetting, if you are jetted too rich then there will not be enough combustion chamber heat to burn off the oil.
I run 25:1 Castor oil, jetted slightly on the rich side and not a trace of oil coming out the pipe.
As stated before reducing the amount of oil in the mix makes for richer running.
Tighten up and seal the exhaust and do a plug chop to confirm the jetting.
Before you make the plug chop run it is important that the float level is correct, the idle is set correctly and there are no air leaks in the system, otherwise the smoke ring may lie about the AFR.
WHEN ALL OF THE ABOVE ARE CORRECT PROCEED WITH THE FOLLOWING.
Warm up motor to operating temp.
Fit new B8ES plug, ride through the gears and hold WOT in 5th or 6th gear for 10 seconds, or as long as you can safely.
Switch off the motor and pull in the clutch, apply brakes to come to a stop quickly.
Take the plug out and replace the old one for the ride home.
Carefully cut the threaded end off the plug to expose the insulator.
There should be a smoke ring of a cardboard or biscuit colour around the insulator.
If it is non existant or a very light colour, you are lean and require a larger main jet.
If it is a lot darker you are rich and may go down a size in main.
I prefer to run a little on the darker side, I may loose a little power but it is worth it for the peace of mind that I won't need a rebuild so soon.
http://www.blasterforum.com/do-yourself-20/how-plug-chop-38674/
http://www.blasterforum.com/engine-13/plug-chop-how-vid-48226/
This is a good to go plug.
This one is a little rich, but I would run it, I like to be on the safe side.
You have to get up a reasonable speed so that you can get the motor to pull strongly.
Then hold it Wide Open Throttle (WOT) for 10 secs or as long as you can.
The idea is not to get speed but to make it pull strong at full throttle to get onto the main jet curcuit.
I find I can safely do it on a short run by applying the brakes some.
If you have not enough room you can use 4th or 5th gear with good results.
I run 25:1 Castor oil, jetted slightly on the rich side and not a trace of oil coming out the pipe.
As stated before reducing the amount of oil in the mix makes for richer running.
Tighten up and seal the exhaust and do a plug chop to confirm the jetting.
Before you make the plug chop run it is important that the float level is correct, the idle is set correctly and there are no air leaks in the system, otherwise the smoke ring may lie about the AFR.
WHEN ALL OF THE ABOVE ARE CORRECT PROCEED WITH THE FOLLOWING.
Warm up motor to operating temp.
Fit new B8ES plug, ride through the gears and hold WOT in 5th or 6th gear for 10 seconds, or as long as you can safely.
Switch off the motor and pull in the clutch, apply brakes to come to a stop quickly.
Take the plug out and replace the old one for the ride home.
Carefully cut the threaded end off the plug to expose the insulator.
There should be a smoke ring of a cardboard or biscuit colour around the insulator.
If it is non existant or a very light colour, you are lean and require a larger main jet.
If it is a lot darker you are rich and may go down a size in main.
I prefer to run a little on the darker side, I may loose a little power but it is worth it for the peace of mind that I won't need a rebuild so soon.
http://www.blasterforum.com/do-yourself-20/how-plug-chop-38674/
http://www.blasterforum.com/engine-13/plug-chop-how-vid-48226/
This is a good to go plug.
This one is a little rich, but I would run it, I like to be on the safe side.
You have to get up a reasonable speed so that you can get the motor to pull strongly.
Then hold it Wide Open Throttle (WOT) for 10 secs or as long as you can.
The idea is not to get speed but to make it pull strong at full throttle to get onto the main jet curcuit.
I find I can safely do it on a short run by applying the brakes some.
If you have not enough room you can use 4th or 5th gear with good results.
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