Idk if this helps but ill throw it out there.. I'm running a keihn pwk 28mm ported stock cylinder dynoport, rad valve, an flotek head mod. Pilot 42 main 155
thats the stock carb right? been a while since i thought about my blaster lol.
270 main jet, stock pilot, stock needle position.
fmf fatty/powercore2, no airbox lid.
bump the main to 280 for winter.
im thinking bro, with all the headaches this 28mm has caused you, you need to invest in Advil and a fifth of something smooth!!!! then re-approach the jetting with a whole new outlook!
have you tryed jetting the main down from the 270?
Blaster Manual says 26mm Mikuni is the stock carb.
oh ok. nevermind then. damn thats a tiny carb!
:-[ Size doesn't matter...as long as it runs and keeps going, that's what's important. 8-|
That is tonight's agenda...the rejetting downward. Talked to my buddy last night that has been riding two strokes since he could talk, working on them before he started school. He pretty much told me 270 sounded a bit high with my characteristics, and to reset my needle to mid clip and drop to a 260. If that works, the "smooth" will be consumed as celebration. I:I
ohhh, is that what she told you. HAHAHA
dont ask me why i think this, i have no idea...
i was just thinking, if a stock 26mm(like my old one) runs with the same mods, a 270 main, it wouldnt stand to reason that a bigger carb, 28mm would flow more air requiring a slighlty smaller jet like a 250-260. doesnt more air usually mean more fuel? idk, im just throwing things out there trying to help. i hope it works man!!! as im STILL waiting for my needle to come from CPW, im not looking forward to my jetting issues either. so, i know how you feel!
You know the slides have different cut out sizes too right? That will also affect jetting in the lower throttle position ranges. On keihin the slides are numbered inside where the cable hooks up. 4-8 is the numbering and 6 is the standard for most of the carbs I believe. I'm not sure if the slides are interchangeable on the Small mikunis like they are on some keihins...
yeah, i guess my question would be, if the 28mm needed to be jetted smaller than the stock 26mm, why not just get a stocker and run it??? no more fussing with this PITA 28????
ok, now i get it! i couldnt understand the jetting relative to the cfm. thanks slicker!!!!If this is the case, then why do any of us get a larger carb, and see big performance gains?
Look at it like this , not that this is just as a reference , I have no idea what actual flow tests are per carb nor could I find any.
But as an example, lets say a 26mm carb can give 500cfm a minute with whatever jetting,
Now a 28mm carb can flow 700cfm a minute again with whatever jetting, you are getting more air/feul mix, in the motor with the 28mm than you would a 26mm.
You really are using more air/feul mix than you think when you increase a carb!
I hope this helps ya understand.
Best advice is plug chop to perfection! The plug dont lie!
ok, now i get it! i couldnt understand the jetting relative to the cfm. thanks slicker!!!!