You have a problem if you have a white plug with a 280 main and stock pipe. I would leak test again.
jetting again....
- Thread starter Fatty98
- Start date
Before you cut another plug, warm it up and ride it then pull out the choke about half way to see what happens.
Bear in mind that you need 3 hands to do it as it is very dangerous to ride with one hand.
Bear in mind that you need 3 hands to do it as it is very dangerous to ride with one hand.
Pardon me all knowing ones, but this is the last recommendation I will give as I know you wolves sit in wait. If you plan on getting on the pipe a lot where it is fun to run up in the rpms, with your lid off, you will melt your piston with only a 280 main jet with the lid OFF, that is If you are at sealevel, you better be in the low 300's on a main. I know this very well because I have drag raced ALOT of passes a lot of years with a 330 main, LID OFF of course, and never so much as fouled a plug and tons of pull on tap with no air leaks. I've had more machines then not that required a much darker plug chop color to achieve spot on jetting. I always have ran 32:1 with Klotz full synthetic techniplate pre-mix oil. Also, do not be fooled into thinking the needle clip positions are off limits to dial in your jetting, because yes, sometimes that's what it takes to get it spot on. I highly suggest you don't run in the high rpms with to small a main jet with lid off to many times, I expect more repeat attacks for this post but what the hell, you never know, maybe something here you can use if you ain't afraid to test and tune not just follow industry recommendations or that of those who only read up online who have jetted there carb once and it was a nice tan color plug chop. I hate to think how many folks wanting honest advice on jetting for there Blaster have come on here and read some of the sh*t I've been reading, probably why there's 18,450 Blaster parts available for sale on ebay, most of which people have parted out. Good luck with it and have fun, that's what this is all about.
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No harm in going richer.
It is normal for the intake close to the carby throat to be dampish but not really wet.
Have you inspected the reeds to see if they are in good condition and sealing well?
I am not going back over ploughed ground as the information given on jetting works well on 95% of all 2 strokes.
Your situation my be in the 5% that differ from the norm.
Why not drop in a #330 main and lower the needle one slot and see what happens, it might just work for you.
your on a stock pipe. And you run a 330 main. Seems rich. I had a 320 main in my bike. With fmf pipe & silencer, airbox lid removed, foam filter well oiled. Stock carb, Middle clip. At elevation in Maryland, pretty close to sea level. The bike ran poorly. I went back to a 300 hundred an the plug chop was slightly rich. I keep it at 300 but a 290 would have done.
Now that being said. I would suggest to the OP that you make absoultly sure your bike is air tight. First and your idel is set properly.
Also make certain your float hight is correct.
Then plug chop and see what you get.
I would reccomend checking everything Else out first tho before throwing a 330 in there tho that seems really rich for a stock pipe.
NOT TO OFFEND ANYONE. Just me 2 cent.
Now that being said. I would suggest to the OP that you make absoultly sure your bike is air tight. First and your idel is set properly.
Also make certain your float hight is correct.
Then plug chop and see what you get.
I would reccomend checking everything Else out first tho before throwing a 330 in there tho that seems really rich for a stock pipe.
NOT TO OFFEND ANYONE. Just me 2 cent.
Appreciate all the help from guys first of all. I took it out today280 middle clip, put the lid back on just so i am only dealing with one change at a time. Float level is perfect at 21mm. It seemed to b a bit grogy and clogged at lower speeds but, once u got past that it pulled like a monster. I tried to adjust idle mix but it was apparently out of its "range" because that only works 0- 1/4 throttle. So when i got home i swithched the needle to the second position and it feels much better in that range. My plug chop is getting some faint color now. It may just need to run around a 300 main with needle in second spot after all. Of course now the carb base gasket is leaking some from all the taking apart, so that may be an air leak. Its def weeping fuel. oh yeah, the reeds are good i double checked them plus they are brand new. If it comes with tits or tires it will always give u a headache.
Idle mix is adjusted before any attempt a jetting as it does have a little effect on the needle up to 1/4 throttle.
Then if you change your needle position you need to do the entire process again as the needle does deliver a minute of fuel at idle.
Idle adjusting.
Set float level.
Start with air screw 1.5 turns out.
Set idle screw so that it has some sort of idle. With TORS it is the big screw under seat on top of unit. With no TORS is is the brass screw midway down carb body.
Warm up motor and then set idle screw for a faster idle, 2000rpm+
Adjust air screw either way to get the fastest idle.
Adjust air screw a little at a time leaving 10 secs or until the motor to responds.
Re adjust idle screw for desired idle .
If you have a full stock pipe set up then anything over 290 will probably be rich, simply because there is a baffle restriction up in the front section of the factory slip on and a section of pipe on the inside of the end cap that causes additional restriction as well, at least, an aftermarket slip on will make a substantial difference in jetting and exhaust flow, from what I've found the stock fatty is pretty much an equivalent to an FMF, I never noticed much more then pretty chrome and a little more noise when I've installed them in the past. I'm running a 270 main with lid on now with clip on the stock third clip setting, I also have a Pro-Circuit slip on, runs crisp and pulls awesome.
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Are you saying that you find very little difference in performance between the stock header and a FMF?
I am not having a shot but referring to a stock pipe as a Fatty could make for some confusion.
The stock header is usually referred to as "stock".
The term "Fatty" is a header pipe manufactured by FMF.
Yea, from my experience with a couple of the last Blasters I've had the stock expansion chamber and an FMF fatty, there wasn't really any distinguishable difference in power gain by the FMF, it just seemed to have a hollower lounder ping to it, they are almost indentical in shape as well. If you have Boysen two stage reeds that will richen up your jetting, I've always had to slightly lean my jetting to dial it in with those, they do flow more fuel.
Generally one needs not to change the jetting when fitting dual stage reeds.
Reeds are not known to increase the airflow but allow a better transition which will show as snappier throttle response.
With the "Fatty" one should not expect much power gain over stock, but what it will do is to bring the power on so much earlier to get up to speed more quickly.
This allows one to use a higher sprocket combo.
Reeds are not known to increase the airflow but allow a better transition which will show as snappier throttle response.
With the "Fatty" one should not expect much power gain over stock, but what it will do is to bring the power on so much earlier to get up to speed more quickly.
This allows one to use a higher sprocket combo.
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Depending on the temperature at sea level #260 to #280 main jet, needle on middle clip should do the job.
Start big then plug chop to perfection.
If you mix a 32:1 add one more jet size, if at 25:1 like I, then go up 2 sizes.
Remember that only a plug chop will give you an accurate result on the correct jetting.
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