blaster jetting with fmf full pipe and reeds
- Thread starter blaster200mike
- Start date
Chopping the threads off and checking the " smoke ring " is the only way to guarantee where your jetting is. Eventually you'll get a ring around the outside of the plug but this takes too long and by then the damage will have already be done if your running lean. Use a new plug for every chop, 3-5 plugs are WAY cheaper then a new top end.
Okay guys back with another q....i put in a 290 jet and tried the best to set my air screw, the throttle response seems very sluggish in the lower end and theres very little low and low middle power, feels like turbo lag when i pull off, it runs really slow and then kicks.....any ideas...do i need a bigger pilot jet? as far as i know im running the stock 32.5. Also, the bike is really sluggish for the first 2 min of riding it doesnt rev very high, once its warm its better...any ideas?
270 main, use the STOCK needle with the clip in the middle position with that 32.5 pilot. see where your at with THAT set up...
Re: blaster jetting with Dmc alien pipe
Thanks man, so you think that my lower end problem is cause im too rich with my needle? P.s Is 270 safe?(then again dmc recommends a 260 with needle pos #5 so im guessing it should be ok) Dont wanna sieze my engine.
On a separate note can someone tell me, or even better show me , how the 'smoke ring' is supposed to look when one cuts off the spark plug threads?
Thanks man, so you think that my lower end problem is cause im too rich with my needle? P.s Is 270 safe?(then again dmc recommends a 260 with needle pos #5 so im guessing it should be ok) Dont wanna sieze my engine.
On a separate note can someone tell me, or even better show me , how the 'smoke ring' is supposed to look when one cuts off the spark plug threads?
Re: blaster jetting with Dmc alien pipe
for my pipe it recommended a 270 main, needle on the fourth clip(rich) and stock pilot. im at 310 main, needle in the middle with the stock pilot, 2 turns out. and it RIPS!
everyones jetting is different, not 2 motors act the same. your pipe manufacturing recommendations are at SEA LEVEL. you gotta go from there. i think the 270 with the needle in the middle is a good start. plug chop and go from there.
as far as pics of plugs n chopping? use the search tab up top, type plug chop and start looking thru all the threads. theres pics and vids and really in depth discussion on the subject. our blasters DEPEND on plug chops!!!
for my pipe it recommended a 270 main, needle on the fourth clip(rich) and stock pilot. im at 310 main, needle in the middle with the stock pilot, 2 turns out. and it RIPS!
everyones jetting is different, not 2 motors act the same. your pipe manufacturing recommendations are at SEA LEVEL. you gotta go from there. i think the 270 with the needle in the middle is a good start. plug chop and go from there.
as far as pics of plugs n chopping? use the search tab up top, type plug chop and start looking thru all the threads. theres pics and vids and really in depth discussion on the subject. our blasters DEPEND on plug chops!!!
Re: blaster jetting with Dmc alien pipe
Thanks. Im guessing that a 310 will be way too big for me at my altitude of 1800m(5500ft), the symptoms with the 290 seemed kinda rich and the bike smoked a lot which as far as i know is a sign of rich jetting? . Maybe the 270 will work, ive got a 270, 280, 290 and 260 main jet at home.
i also wanted to find out....if i add a uni filter and remove my airbox lid, how much should i go up in jetting, 10?
Thanks. Im guessing that a 310 will be way too big for me at my altitude of 1800m(5500ft), the symptoms with the 290 seemed kinda rich and the bike smoked a lot which as far as i know is a sign of rich jetting? . Maybe the 270 will work, ive got a 270, 280, 290 and 260 main jet at home.
i also wanted to find out....if i add a uni filter and remove my airbox lid, how much should i go up in jetting, 10?
Re: blaster jetting with Dmc alien pipe
probably up one size, maybe 2. like i said, only way to be SURE is to plug chop!
probably up one size, maybe 2. like i said, only way to be SURE is to plug chop!
As posted earlier.
Look up elevation jetting.
DMC also says to use the stock needle on the richest setting.
I have found that the Alien does tend to drink a little.
My bike at sea level with foam filter directly on the carb mouth, runs slightly rich on a #320 main.
I did however lower the needle one clip.
I woul be starting at #290 and plug chopping to perfection.
Heres one posted by Awk a while ago, 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.
Look up elevation jetting.
DMC also says to use the stock needle on the richest setting.
I have found that the Alien does tend to drink a little.
My bike at sea level with foam filter directly on the carb mouth, runs slightly rich on a #320 main.
I did however lower the needle one clip.
I woul be starting at #290 and plug chopping to perfection.
Heres one posted by Awk a while ago, 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.
Nice pics Blaaster!!! should he AT LEAST move the needle if hes running That Rich??? (lol, you hate that word!) i would think with the airbox lid on and a stock filter maybe a 270 to start thats why....
If you are having trouble setting the air screw, the float level may be wrong, or you have an air leak.
The idle must be set right be fore you attempt to jet.
It should take up to 2 minutes to warm up the motor, but you should not be riding to warm it up
Re: blaster jetting with dmc pipe
Where would the air leaks be if there were any the carburetor, exhaust gasket? where else?
Where would the air leaks be if there were any the carburetor, exhaust gasket? where else?
Re: blaster jetting with dmc pipe
Reed manifold, where the reeds meet the engine case is a notorious spot. Basicaly, EVERYWHERE on a 2 stroke is prone to air leaks. Do you have a leak tester? If not, you should Definitly Get one!!!
Reed manifold, where the reeds meet the engine case is a notorious spot. Basicaly, EVERYWHERE on a 2 stroke is prone to air leaks. Do you have a leak tester? If not, you should Definitly Get one!!!
Re: blaster jetting with dmc pipe
Kay guys. I did a plug chop on my 290 with needle position #5, admittedly i did ride for longer than some recommend for jetting but i was at WOT, i used a brand new plug, looking at the results(attached) im thinking im a bit rich at the moment. What do u guys think?
Id like to add that im only having this poor low end performance since i installed the new pipe, the bike was running a 260 main jet(i dont know why) before i installed the new pipe and it was running pretty well, i wasnt having any low end problems, weve checked and cleaned the carb and reeds so i highly doubt that this problem is caused from any leaks or serious problems. Could the problem be from an improperly sealed exhaust gasket? or maybe a clogged pilot jet? We also set the float level to 20mm, it was originally lower than that.
Kay guys. I did a plug chop on my 290 with needle position #5, admittedly i did ride for longer than some recommend for jetting but i was at WOT, i used a brand new plug, looking at the results(attached) im thinking im a bit rich at the moment. What do u guys think?
Id like to add that im only having this poor low end performance since i installed the new pipe, the bike was running a 260 main jet(i dont know why) before i installed the new pipe and it was running pretty well, i wasnt having any low end problems, weve checked and cleaned the carb and reeds so i highly doubt that this problem is caused from any leaks or serious problems. Could the problem be from an improperly sealed exhaust gasket? or maybe a clogged pilot jet? We also set the float level to 20mm, it was originally lower than that.
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Re: blaster jetting with dmc pipe
Not bad, yes a hair on the rich side, if your problems are still on idle to 1/8 throttle, That is the pilot/airscrew.
Really think you would be spot on with a 280, needle middle clip, stock pilot and a properly adjusted air screw.
Yes an exhaust leak does affect jetting, these are scavager motors!
Fix that leak first, If ya haven't airleak tested it ya should after that.
Since you already did the float adjustment, I'd take the carb apart clean it good , blow dry with some compressed air and reinstall.
Then set correct idle speed I like about 1000 or so, I believe the manual says 1400 max??
Next I would warm the motor up about 3-4 minutes varing rpms (not riding it) then I'd start the air screw adjustment at 1.5 turns out, try a half turn out to 2 turns out and wait two minutes let engine respond, you are looking for highest idle.. once you have found highest idle, that will tell you if you need a larger or smaller pilot jet. More than 2.5 turns out means you need a smaller pilot, the motor wants more air. Less than 1 turn out means that it wants more gas, richer larger pilot.
If you stay in the 1.5-2.5 turns range I'd leave that pilot in there, and now you want to adjust that air screw for good throttle response, this is fine tuning and is done in 1/4 turns. I have never had to go more than a half turn for best throttle response after I found my highest idle spot. Any air leak/exhaust leak will make this part harder to dial in.
Not bad, yes a hair on the rich side, if your problems are still on idle to 1/8 throttle, That is the pilot/airscrew.
Really think you would be spot on with a 280, needle middle clip, stock pilot and a properly adjusted air screw.
Yes an exhaust leak does affect jetting, these are scavager motors!
Fix that leak first, If ya haven't airleak tested it ya should after that.
Since you already did the float adjustment, I'd take the carb apart clean it good , blow dry with some compressed air and reinstall.
Then set correct idle speed I like about 1000 or so, I believe the manual says 1400 max??
Next I would warm the motor up about 3-4 minutes varing rpms (not riding it) then I'd start the air screw adjustment at 1.5 turns out, try a half turn out to 2 turns out and wait two minutes let engine respond, you are looking for highest idle.. once you have found highest idle, that will tell you if you need a larger or smaller pilot jet. More than 2.5 turns out means you need a smaller pilot, the motor wants more air. Less than 1 turn out means that it wants more gas, richer larger pilot.
If you stay in the 1.5-2.5 turns range I'd leave that pilot in there, and now you want to adjust that air screw for good throttle response, this is fine tuning and is done in 1/4 turns. I have never had to go more than a half turn for best throttle response after I found my highest idle spot. Any air leak/exhaust leak will make this part harder to dial in.
Re: blaster jetting with dmc pipe
Thanks man. Another thing i noticed. The bike seems to battle a lot more in first and second gear, but runs much better in third or fourth etc. Any idea why that is.......p.s i would do a leak down test but im not really sure where to get a tester( i live in south africa).
P.s, i noticed when turning the air screw a mixture of like oily petrol came out....could that be blocking my air screw intake?
Thanks man. Another thing i noticed. The bike seems to battle a lot more in first and second gear, but runs much better in third or fourth etc. Any idea why that is.......p.s i would do a leak down test but im not really sure where to get a tester( i live in south africa).
P.s, i noticed when turning the air screw a mixture of like oily petrol came out....could that be blocking my air screw intake?
Re: blaster jetting with dmc pipe
1. Sounds definetly like a carb issue, I'd take it off completely disassemble clean with carb cleaner then with compressed air if possible. Check float level, stock is 20-21.5mm.
2. I can ship u a leak tester they are $43 for international shipping it takes 2 weeks but never lost one yet! been to japan, down under, canada, rico, germany. I'm worldwide brutha! I couldn't resist that!
3. see #1 I:I
1. Sounds definetly like a carb issue, I'd take it off completely disassemble clean with carb cleaner then with compressed air if possible. Check float level, stock is 20-21.5mm.
2. I can ship u a leak tester they are $43 for international shipping it takes 2 weeks but never lost one yet! been to japan, down under, canada, rico, germany. I'm worldwide brutha! I couldn't resist that!
3. see #1 I:I
Very rare to have bad tranny gears, but is possible. Is there proper oil in the motor (crankcase?) Oh, I know one of the obvious, maybe the silencer needs repacked! (soaked with oil or hard as a brick?). Air filter new or clean? Really sounds like a dirty carb issue and possibly an air leak.
