speed carb problem please help
- Thread starter wackey101
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motorpsycho
Active Member
if you have to leave the choke on, the mixture it may be too lean. (it's getting too much air and by choking it, you are reducing the amount of air that it's taking in).
you may have to play with the air-fuel mixture screw (if it has one), or you have an air leak somewhere (check the carb to intake seal and make sure there is no extra air being sucked in around it.)
moving the e-clip may help but you would probably want to lower the clip which will rasie the needle richening the mixture.
my guess is an air leak tho because the engine shoudl still run without the choke on , even if the needle is set as lean as it can be. moving the needle will not lean it out enough to cause the problem you are describing.
you may have to play with the air-fuel mixture screw (if it has one), or you have an air leak somewhere (check the carb to intake seal and make sure there is no extra air being sucked in around it.)
moving the e-clip may help but you would probably want to lower the clip which will rasie the needle richening the mixture.
my guess is an air leak tho because the engine shoudl still run without the choke on , even if the needle is set as lean as it can be. moving the needle will not lean it out enough to cause the problem you are describing.
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motorpsycho
Active Member
the most effective way to richen the mixture (if you really have to) is to re-jet the carb.
changing the e-clip will only help from idle to about 1/2 throttle because after 1/2 throttle the needle is totally away from the jet and hos no effect on the air-fuel ratio.
changing the e-clip will only help from idle to about 1/2 throttle because after 1/2 throttle the needle is totally away from the jet and hos no effect on the air-fuel ratio.
hey
well i richen the mixutre as much as i could cover the air leakes it was were the intake was but still was bogging but at least it worked then i richen the mixure as much as i could works beautifully but still bogs but not as much and only if i go full throttle all of a sudden if i want to re jett it what size should i get to fit it cause i mine is the standerd
thnx
well i richen the mixutre as much as i could cover the air leakes it was were the intake was but still was bogging but at least it worked then i richen the mixure as much as i could works beautifully but still bogs but not as much and only if i go full throttle all of a sudden if i want to re jett it what size should i get to fit it cause i mine is the standerd
thnx
motorpsycho
Active Member
yes, as i mentioned, moving the e-clip on the needle will only help from idle to about 1/2 throttle. If it's still bogging, chances are that it's still too lean.
USUALLY a bog at wide open throttle is caused by the fuel-air ratio being too lean.
you will have to take your float bowl off and figure out what size jet is in it, and then go from there.
I'm not sure what jets will fit this carb tho. sick bike parts sells many sizes of delorto jets, but I have no idea if the threads on those jets are the same as the threads on the jet that's in the speed carb.
lets say that your carb has a .70 jet in it, you would want to richen it up to like a .72 or .74.
always make jet changes in small increments (as far as the jet sizes go). you never want to make a big jump in size, like from a .70 to a .66.
it takes time going in small increments, but this helps you fine tune it.
lets say that you go from a .70 to a .72 and it runs better. now go from a .72 to a .74 and see how it runs. it it runs even better, then go frm a ,74 to a .76. if this change makes it start running worse, drop back to the .74 jet.
there is a lot of messing around in tuning a carb by changing the jet. it's not like you can just guess and start throwing random jets in it to see how each one affects how the engine runs.
USUALLY a bog at wide open throttle is caused by the fuel-air ratio being too lean.
you will have to take your float bowl off and figure out what size jet is in it, and then go from there.
I'm not sure what jets will fit this carb tho. sick bike parts sells many sizes of delorto jets, but I have no idea if the threads on those jets are the same as the threads on the jet that's in the speed carb.
lets say that your carb has a .70 jet in it, you would want to richen it up to like a .72 or .74.
always make jet changes in small increments (as far as the jet sizes go). you never want to make a big jump in size, like from a .70 to a .66.
it takes time going in small increments, but this helps you fine tune it.
lets say that you go from a .70 to a .72 and it runs better. now go from a .72 to a .74 and see how it runs. it it runs even better, then go frm a ,74 to a .76. if this change makes it start running worse, drop back to the .74 jet.
there is a lot of messing around in tuning a carb by changing the jet. it's not like you can just guess and start throwing random jets in it to see how each one affects how the engine runs.
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speed carby smaller jets than nt carb???
hi
i have a speed carby and was bogging alot because was too lean i had the pin on the richest setting and still slightly boged so i had a look at my jet than had a look at my old jet turns out the stock nt carb has a bigger jet for some reason wich the speed carby is ment to be bigger as soon as i swapped the old one into the speed carby the bogging stoped but now my throttle is less responsive
wich is really bigger please help
hi
i have a speed carby and was bogging alot because was too lean i had the pin on the richest setting and still slightly boged so i had a look at my jet than had a look at my old jet turns out the stock nt carb has a bigger jet for some reason wich the speed carby is ment to be bigger as soon as i swapped the old one into the speed carby the bogging stoped but now my throttle is less responsive
wich is really bigger please help
Skyliner70cc
Active Member
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Moast caurb jetz hav eh numbar onn them dat realats two da sise uv da jett. Cinse our caurbs donte hav a lo speid neadel valv, da mane jett iz a compramize att da eckspense uv tooning threwout da rpm rainge. Yoo hav two deside wat it iz u want hi spead powar than lo speid powar wil sufer an vice verse. Ef a fine tooned injun iz ur gole, than konsidar a CNS karb.
