Man that just seems super lean to me, if you are at sealevel, I say just for sh*ts and giggles, lid off, second needle clip postion down from top, with a 330 main, 14tooth front sprocket you will ride a Blaster that will straight rock you, I bet you a cup of coffee you will never have felt it pull so hard in your life.
jetting again....
- Thread starter Fatty98
- Start date
The plug looked the best and ran the best at 270. I have since made multiple changes to my motor. When I did jet it I started with a 300 main. It ran pretty good, but the plug was to dark. Then went to 280 and it was perfect. It was between 30-40 degrees that day. It pulled a lot harder and cleaned out better with the 280. I run the 270 in the warmer months.
I generally try and get my jetting close enough to raise the needle one position in the winter and lower one position in the summer, I've never fouled a plug, burnt a ring or destroyed a piston on any two stroke that I have built with my jetting techniques and there's been a bunch, I get them set to where the idle is crisp and no steady rev to keep it running. The first Blaster I learned had a 330 main in it when I first got it from a buddy was the Vito's 240 Blaster that I had, strong quad, I never pulled it down other then removed the head to check the top of the piston and how the premix was burnin off, so not sure what all it had done to it. I remember thinking "Damn that's a big ass main jet," as I got other Blasters I found that with the modds I was doing I could perfectly tune each one of them to that same size 330 main with the lid off right here on the coast. When I ride, I ride a 3000 acre atv park about an hour away and I ride from morning till night, drag racing, trail riding and a little mx track riding so not much cool down time, it's gotta be right.
Well whatever works man. Better to be rich than lean.
Also the last time we went riding I went on a long trail ride then ripped it through all 6 gears. Then pulled the clutch in and the cylinder was 260 degrees with the laser temp gun.
HOLY sh*t!! 260 degrees!! Proofs in the pudding, 220 on a two stroke cylinder head is about as hot as you want it to get with proper jetting from what I've read, that's hot. I even noticed when I changed up to the 270 with my lid still on it actually took longer for my jug to warm up before I went on a ride.
I am going to tell you that you are wrong. There is plenty of reading on this. Here is some. 260 is damn near perfect!
/2-stroke/what-not-to-do-to-your-aircooled-motor!/15/
http://www.blasterforum.com/engine-13/temperature-compression-49492/
http://www.blasterforum.com/engine-13/blaster-operating-temp-28750/
Of course the last post was from somebody who didn't know what they are talking about.
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That's cool, ok, keep jetting the way you do if you feel its right for you, I know what works excellent for me and has for over a decade on a lot of the same machines. I personally don't feel there's been enough research on jetting a blaster by the big companies as this has pretty much always been considered an entry level quad to them, also its basically a recommendation by them, they are not gonna take the time to go out and ride day after day, adjust and dial in the jetting time and time again at different elevations to achieve a perfect jetting recommendation, its just a baseline. I'm not gonna take a chance on frying my piston and destroying my cylinder, not only a plug chop but I can feel when the jetting is out and is not dead on. Plug chops are not as accurate as everyone raves, you can't just cruise around the neighborhood then pull through the gears to WOT and expect to get a clear and perfect reading. My 08 400 Kingquad for example took 5 main jet sizes larger with just a Leo Vince slip on and air box lid still on to achieve perfect, crisp jetting and pulls super strong. I know that's a 4 stroke but jetting is an exact science, its either wrong or its right. I've put in so many Dyno Jet Jet kits that I can tell you for fact that here at sea level I have to install the largest main jet in the kit that always guarantees near perfect jetting even though they recommend the one second to the largest nearly everytime with airbox lid off. The only kits I have installed that have been dead on are the JD (James Dean) jet kits I've put in dirt bikes, they nail it perfect everytime with there kits. I know there's always gonna be lengthy discussions about jetting but it all boils down to who's got the most time to get it perfect and who is willing to pull the carb off time and time again and not just settle for a baseline recommendation.
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If plug chop is done correctly it is very accurate. I have an EGT (Exhaust gas temp.) temp guage, which is the most accurate way to jet a bike. It came on a bike that I bought. I will be using it to jet my next build. Then I will do a plug chop and compare. When using the EGT 1,100 degrees is spot on.
This statement tells me that you must be very confused and do not understand the workings of a carby.
Altering the main jet or pilot jet will have minimal effect on the needle.
The needle starts its work at idle till around 1/4 throttle and is the primary supplier of fuel up to 3/4 throttle, where the main jet takes over.
The needle needs only to be adjusted to compensate for temperature/humidity/elevation and a change in oil/fuel ratio.
Another thing you confuse me with is when you allow better breathing by removing the lid and compensate by fitting a #330 main, you then lower the needle one position which leans out 1/4 to 3/4 throttle, why, you have increased the breathing here also.
You say you use jet kits, do they contain genuine Mikuni jets as some kit suppliers use shonky suppliers and the jets are not true.
I run a pipe that calls for a #260 on a stock setup, the same as a FMF Fatty.
I use a stock 26mm carby at sea level, 25:1 pre mix and a foam filter directly on the carby throat and only run a #320 main jet in the dead of winter.
I prefer to run on the rich side and the main can come back as much as a #300 in summer.
I am now going to sit down and do a little more research on 2 strokes and their jetting, not only Blasters but all 2 strokes.
By the way guys in future take what I say with a pinch of salt as I am almost convinced that I do not know what I am talking about.
Apparently according to some people, Wifesblaster knows stuff all also.
Zero confusion here, although the pilot actually meters fuel through the entire fuel delivery range, the needle is for fine tune adjustments and will make the difference of whether you need one size large main jet or one size smaller, one clip position will slightly richen or lean the fuel mixture as you raise or lower it, increase in main size will compensate for clip settings allowing for ideal fine tuning. These facts are without question, search and dispute as you wish.
I just try to give recommendations based on my experience with these bikes. In no way do I claim to be right all the time and I understand what works for me might not work for others. Once I get the EGT hooked up I will post results and do a comparison with a plug chop.
Here's a link to all my Blasters in the Vid/Pics section if your trying to discredit me. I've had so much sh*t I almost can't remember them all.
You guys can go gang bang somebody else, I know what the f*ck i'm doing.
http://www.blasterforum.com/pics-vids-9/pics-my-blasters-past-current-56106/
You guys can go gang bang somebody else, I know what the f*ck i'm doing.
http://www.blasterforum.com/pics-vids-9/pics-my-blasters-past-current-56106/
It's all good. We are here to learn and help others. Our opinions and techniques will vary.
OP.... Sorry your thread got ruined. Feel free to start a new thread or try to get this one back on topic.
OP.... Sorry your thread got ruined. Feel free to start a new thread or try to get this one back on topic.
Its all good "gentleman" . Lol. I will b jetting today and starting with a 270 i think as i discovered i had a 240 in there already. If u guys remember i orig stated that my chop was like bright white so im pretty sure it needs to go up quite a bit haha. The needle was in second slot so im not sure if im going to move it or not. Thoughts?
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Just a change in air filter should call for a #240 or #250 main.
Taking the lid off will call for an increase of two more sizes.
Clip in middle slot should work just fine.
May I ask the results of the leak test, what was the test pressure and how long was it held for.
If your plug chop returns a white insulator with that jetting then suspect a problem somewhere, are you getting a full WOT?
You mentioned that your needle was set low, are you applying the throttle to full WOT in every gear or are you riding up to revs with the needle circuit.
The lean needle could be the reason for a white insulator.
Do not fit any larger jet or fiddle with the needle to try to compensate for an underlaying problem.
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Not wishing to insult you but did you follow this \/ \/ \/ procedure when doing the plug chop.
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 circuit.
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.
Yea thx for the tutorial but, i understand how its done. I also live on the train tacks so room to run isnt a problem. My chop today was white again with no lid and a 280 main. I will be checking further for air leaks. I will also add that the air filter side of intake seems pretty wet. hmmm. the plot thickens
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