i kinda figured that... is it the needleclip then? i mean it wasnt throwing alotta hiccups i felt like maybe 2 at 3/4 throttle looking back now
whats jets to use on 28m pwk?♥
- Thread starter Demo4o1
- Start date
If you were holding the throttle there then it might cough once in a while. I think that without an airbox lid and this temp that you are lean. I also stated that I don't agree with the timing advance on a stock bike. There are a lot of issues that relate when jetting is taking place.
so u think im lean.. i should try up the mains? bc when i ran the 160 main it was bogging alot. i tried 155 and it was ehhhhh... so i tried 150 and the 150 felt just about right. i might fiddle with the timing again and see if i feel a difference. then that means i gotta mess with the jetting again.. so ure saying the timing mod really boost me with my current mods but actually worst? or should i try +3 instead of the +4?
What I am saying is that with a stock motor and compression. The octane that is in the fuel does not require any additional burn time.
The jetting is something that can not be set the same from bike to bike. It is such that it needs fiddled with to get it correct. Then once the temperature changes from morning to night and with the seasons as well, the jetting will change as well. Especially when the engine and fuel system has modified.
The jetting is something that can not be set the same from bike to bike. It is such that it needs fiddled with to get it correct. Then once the temperature changes from morning to night and with the seasons as well, the jetting will change as well. Especially when the engine and fuel system has modified.
so u think im lean.. i should try up the mains? bc when i ran the 160 main it was bogging alot. i tried 155 and it was ehhhhh... so i tried 150 and the 150 felt just about right. i might fiddle with the timing again and see if i feel a difference. then that means i gotta mess with the jetting again.. so ure saying the timing mod really boost me with my current mods but actually worst? or should i try +3 instead of the +4?
From what Ive gathered (not sure why I didnt use it in my own instance - I need to dick around with mine again now), and personal experience in my own jetting, you use the idle circuit to figure out what pilot jet you need.
So, you set your pilot first. You install where you THINK you need it, and you warm the bike up, and set your idle. If you have to screw the idle screw all the way out to get it to idle, youre too rich. If you have to turn it all the way in youre too lean. You want it 1.5-2 turns out to be ideal. So, get your idle down and youre pretty close to dialed in with your pilot jet.
Then set your main, You want to put in say, a 160 (Im using that cause you said it ran too rich with a 160 in it), and if it bogs out at WOT, then drop a size, until it isnt bogging out anymore.
Once you get your pilot and main dialed in, then you set your needle. Move the clip to the top of the needle if youre too rich down low and it bogs on transitional throtle (like mine), or if it revs up too fast or pops (when youre lean, at lower RPMs, the engine speed picks up faster than it should), then you want to move the clip toward the bottom of the needle.
Remember, the needle affects the main circuit only, but the main circuit does affect the midrange as it transitions off the pilot over to the main, theres a point where both jets are flowing fuel and the needle helps balance that so you dont overfuel, or run lean for a minute.
Due to the nature of the main/needle, most guys dont have to change the pilot out for modifications, once they get their idle down, they just adjust the needle and change the main.
Again, this has been MY experience with Keihin carbs, and I had to learn through the school of trial and error. But whatever Ive done with mine has been for what I feel, right, because Ive ridden my quad over a range of 5000 feet differences all last season (between 4000 to 10000 feet base elevations), and I havent had to change my jetting. I understand if I were to drop my main at the higher elevations Id get more performance, but Im still not too rich to foul a plug, and too lean to frag my engine. and to me thats important.
Hope this helps.
So, you set your pilot first. You install where you THINK you need it, and you warm the bike up, and set your idle. If you have to screw the idle screw all the way out to get it to idle, youre too rich. If you have to turn it all the way in youre too lean. You want it 1.5-2 turns out to be ideal. So, get your idle down and youre pretty close to dialed in with your pilot jet.
Then set your main, You want to put in say, a 160 (Im using that cause you said it ran too rich with a 160 in it), and if it bogs out at WOT, then drop a size, until it isnt bogging out anymore.
Once you get your pilot and main dialed in, then you set your needle. Move the clip to the top of the needle if youre too rich down low and it bogs on transitional throtle (like mine), or if it revs up too fast or pops (when youre lean, at lower RPMs, the engine speed picks up faster than it should), then you want to move the clip toward the bottom of the needle.
Remember, the needle affects the main circuit only, but the main circuit does affect the midrange as it transitions off the pilot over to the main, theres a point where both jets are flowing fuel and the needle helps balance that so you dont overfuel, or run lean for a minute.
Due to the nature of the main/needle, most guys dont have to change the pilot out for modifications, once they get their idle down, they just adjust the needle and change the main.
Again, this has been MY experience with Keihin carbs, and I had to learn through the school of trial and error. But whatever Ive done with mine has been for what I feel, right, because Ive ridden my quad over a range of 5000 feet differences all last season (between 4000 to 10000 feet base elevations), and I havent had to change my jetting. I understand if I were to drop my main at the higher elevations Id get more performance, but Im still not too rich to foul a plug, and too lean to frag my engine. and to me thats important.
Hope this helps.
True, that is the transition to the main ( which was prob too big). Mine loves the 45 pilot, tho.
Interestingly, I had to dial back to a 135 main when I switched to a pod filter. A 140 might be even better but it hated the 158 I was running with the stock type airtube.
You are talking about the air adjustment screw here. That is the one that needs to be 1 1/2 to 2 turns out. This will allow the the idle to vary to dial in the pilot jet.If it were mine, it would have a 35 pilot. I never worry about a 2 stroke when it comes to the idle part. As long as it idles fo 10-15 seconds that is good enough for me. I would rather it be crisp and quick when you hit the gas.
very informative guys... i havent fiddled with my needle but i found the 150 to be right. as for the pilot i got in the 45 and tried the 40. it didnt really feel right to me although "feeling right" could nothing or something. 45 idles tho with 2 turns out if i run the 40 that could make it too lean right? the lower the leaner? btw when it was bogging it was in 1/4 throttle and 1/2. would that be the pilot? maybe be 160 was fine afterall and was just my pilot? i gotta mess with it again tmrw altho it feels fine now i wanna make sure i have it dialed in RIGHT
If its bogging 1/4 to 1/2 throttle, its actually likely your needle. Its likely getting too much fuel in that range cause the needle is coming off at too high of a rate. Try moving the needle DOWN by raising the location of the c clip on the top of it. Play around with it. Go one step at a time and see if it gets better.
i took it for a real good run today (i logged my ride
http://maps.google.com/maps/ms?ie=UTF&msa=0&msid=201960734073825613630.0004a241683b8ce95cf97 )
and it ran real nice at the 45/150. i mean i rode her today harder than ive ever ridden it and i feel a big improvement with the carb and jetting. as far as the jetting i let my boys ride it too and they said it feels perfect and theyre mechanically knowledgeable. i think im gonna try the 40/160 and lower my needle like luni suggested and see how that runs. i wanna dial it in perfect. motor is runnin hotter with the advance timing and she burns alot more gas then ever with the new carb. ive never ran outta gas on a trail til today i thought it was a prob with the carb when it died out. or fouled a plug or what not. so changed the plug on the trail and my boy said do u have gas? i didnt even check bc right before the ride i filled it up. but i checked and I was really outta gas
thank god for reserve switch
http://maps.google.com/maps/ms?ie=UTF&msa=0&msid=201960734073825613630.0004a241683b8ce95cf97 )
and it ran real nice at the 45/150. i mean i rode her today harder than ive ever ridden it and i feel a big improvement with the carb and jetting. as far as the jetting i let my boys ride it too and they said it feels perfect and theyre mechanically knowledgeable. i think im gonna try the 40/160 and lower my needle like luni suggested and see how that runs. i wanna dial it in perfect. motor is runnin hotter with the advance timing and she burns alot more gas then ever with the new carb. ive never ran outta gas on a trail til today i thought it was a prob with the carb when it died out. or fouled a plug or what not. so changed the plug on the trail and my boy said do u have gas? i didnt even check bc right before the ride i filled it up. but i checked and I was really outta gas
thank god for reserve switch
Thats odd you have fuel consumption issues. My blaster with my 28 and the jetting I have goes about as far as a bone stock blaster that rides with us does.
I definately wouldnt recommend you upping your main jet if you are already having problems, youll just make it worse, and it prolly wont run right anyway.
I definately wouldnt recommend you upping your main jet if you are already having problems, youll just make it worse, and it prolly wont run right anyway.
I'm not having any issues. It runs great now. I just wanted to dial it perfect. I'm gonna fiddle with the jetting in a bit
Where every1 go?? So today I ran the 40/160 3rd clip. Took it for a spin WOT. I think she's a tad rich so idk if I should lower the needle, or run the 155 main. As for the pilot idk it didn't really feel a difference I think its the same. Only a plug chop will tell.. before this I ran the 45/150 middle clip and it felt just right. I just wanna dial it just right
Well, lowering the needle on WOT wont really do much, lowering the needle affects the midrange jetting of the quad.
Its also been a few since you made this thread. So what did you end up doing with your jetting?
Its also been a few since you made this thread. So what did you end up doing with your jetting?
sh*t i forgot. i think i still have it at 40/160.. lmao . i think my 3/4 range isnt dialed in the way i want it. i jsut havent had the time to fiddle with it i guess
. i think my 3/4 range isnt dialed in the way i want it. i jsut havent had the time to fiddle with it i guess
