need jeting help
- Thread starter cody2T
- Start date
That sounds like something other then your main causing that ... Is it only in 4th ? Do you have the same problem in 5th and/or 6th ?
honestly i cant get it out of fourth where iam at but 4th gear has diminished acceleraition and bogs when i switch from third pinned no air leaks brand new jug brand need bottom end clean carb in just not sure where should i start with the lid off it dogs with a 290 with lid on
Blaner
Your Friendly South African Ambassador
Stick with the 290 and remove the air lid. Does it make a difference?
if it improves, and you want to run with the lid, it means you are too rich so go down a size or two.
if it improves, and you want to run with the lid, it means you are too rich so go down a size or two.
Blaner
Your Friendly South African Ambassador
Well it seems you need to do a leak test my friend! If its bogging worse without the lid, it means its a lean bog. Dangerous! and if you lean bogging with a 290 in and you not even ported, id be very worried.
Do not ride that bike until you do a leak test and determine if it is sucking air or not.
How are you cleaning the carb? A quick douch won't work. Have you taken it ALL apart? you can see through the holes in the jets? How about the emulsion tube/needle jet? Did you set float level? Carb vents clear? Petcock clean? Vent open? Do a test, using a glass or metal container, drain gas into it for at least the amount of time it takes you to get to fourth gear, and see if the rate of flow slows down.
BTW, your text lingo makes it hard to follow what you are saying, try English.
BTW, your text lingo makes it hard to follow what you are saying, try English.
The following process may help to diagnose the problem.
PLUG CHOP.
Before you make the plug chop run it is important that the float level is correct, the idle is set correctly and there are no air leaks in the system, otherwise the smoke ring may lie about the AFR.
WHEN ALL OF THE ABOVE ARE CORRECT PROCEED WITH THE FOLLOWING.
Warm up motor to operating temp.
Fit new B8ES plug, ride through the gears and hold WOT in 4th 5th or 6th gear for 10 seconds, or as long as you can safely.
Switch off the motor and pull in the clutch, apply brakes to come to a stop quickly.
Take the plug out and replace the old one for the ride home.
Carefully cut the threaded end off the plug to expose the insulator.
There should be a smoke ring of a cardboard or biscuit colour around the insulator.
If it is non existant or a very light colour, you are lean and require a larger main jet.
If it is a lot darker you are rich and may go down a size in main.
I prefer to run a little on the darker side, I may loose a little power but it is worth it for the peace of mind that I won't need a rebuild so soon.
http://www.blasterforum.com/do-yourself-20/how-plug-chop-38674/
http://www.blasterforum.com/engine-13/plug-chop-how-vid-48226/
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.
Oops broken link, sorry.
You have to get up a reasonable speed so that you can get the motor to pull strongly.
Then hold it Wide Open Throttle (WOT) for 10 secs or as long as you can.
The idea is not to get speed but to make it pull strong at full throttle to get onto the main jet circuit.
I find I can safely do it on a short run by applying the brakes some.
If you have not enough room you can use 4th or 5th gear with good results.
PLUG CHOP.
Before you make the plug chop run it is important that the float level is correct, the idle is set correctly and there are no air leaks in the system, otherwise the smoke ring may lie about the AFR.
WHEN ALL OF THE ABOVE ARE CORRECT PROCEED WITH THE FOLLOWING.
Warm up motor to operating temp.
Fit new B8ES plug, ride through the gears and hold WOT in 4th 5th or 6th gear for 10 seconds, or as long as you can safely.
Switch off the motor and pull in the clutch, apply brakes to come to a stop quickly.
Take the plug out and replace the old one for the ride home.
Carefully cut the threaded end off the plug to expose the insulator.
There should be a smoke ring of a cardboard or biscuit colour around the insulator.
If it is non existant or a very light colour, you are lean and require a larger main jet.
If it is a lot darker you are rich and may go down a size in main.
I prefer to run a little on the darker side, I may loose a little power but it is worth it for the peace of mind that I won't need a rebuild so soon.
http://www.blasterforum.com/do-yourself-20/how-plug-chop-38674/
http://www.blasterforum.com/engine-13/plug-chop-how-vid-48226/
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.
Oops broken link, sorry.
You have to get up a reasonable speed so that you can get the motor to pull strongly.
Then hold it Wide Open Throttle (WOT) for 10 secs or as long as you can.
The idea is not to get speed but to make it pull strong at full throttle to get onto the main jet circuit.
I find I can safely do it on a short run by applying the brakes some.
If you have not enough room you can use 4th or 5th gear with good results.
Last edited:
I live near JBRoc and run the Pro Circuit pipe, no lid, oil injection all stock motor. I have a 280 in it, if you are premixing the 290 sounds about right.
I'm running a 280 main which is on the rich side, stock pilot, needle clip in the middle and I'm 1 and 3/4 turns out on the air mixture screw. Lid on but I removed the snorkel.
Like bummer said I think your main jet should be about right at 290, it seems your problem is being caused by something else ? Being that it accelerates fine 1st through 3rd but drops off when you shift onto 4th has me puzzled. Judging solely by the fact you bog out once you shift into 4th, that does point to a very lean condition almost certainly caused by an air leak ... Tho it does not make sense to me why you wouldn't have the same issues in your other gears as well !
Did you happen to modify or remove anything around your airbox or front fenders that could have changed the aerodynamics and is causing air to be forced into the suction side of the air filter at the higher speeds. Hence the fourth gear is where it starts, thats getting up there in speed and moving lots of air around.
Just a thought.
Just a thought.
Good thought but it would need a ram air scoop to make a difference.
More than likely it's lean and doesn't show up until there is a heavier load placed on the engine
