ninjette.org - View Single Post - Reviving a Ninja 250 - Low compression

Bob KellyIII · February 5th, 2022, 01:49 AM

a quicker easier check would be just cover the throat of the carb with your hand and see if that cylinder picks up.... that is if you have the air box off and can reach it.... stuff is so close on a ninja it makes even simple tests like that dificult.... LOL of course that will depend on if you have fuel reaching that carburator too because if that carb is dry that won't change a thing !
but if it's running on one cylinder and you put your hand over the other carb and it picks up that cylinder too then you found the problem it's just not getting fuel through the carb....for what ever reason
....
incidently, the cylinder that was not firing on my bike was wet as it could be and it did look like oil too running on one cylinder will pump oil in the dead cylinder because it is not firing , I changed the plugs in my bike as well just to be sure and it still would not fire ... I had the boots off the air cleaner side and could reach down and cover the throat of the carb carefully with 2 fingers and that cylinder immediately fired up ! I thought AH HA !!! no fuel !
because the choking of that side made it much richer and it fired up !
that told me it wasn't getting fuel at idle !
I played with it for a few days because I dreaded taking the carbs off one more time ... so I got the idea of adjusting out the air screws a little more
and soon as I did that she started to run on both cylinders at idle ..which it had never done that before ! .....
but unfortunately 3 months later it is doing the same thing again dropping to
1 cylinder at idle.... so I really need to pull the carbs and clean then again !
.....
the problem with cleaning these carbs is you cannot get into ALL the passage ways on the idle curcuit with anything.... I even bought a carb cleaning tool off Amazon and it worked great but it is useless at cleaning the crossover area deep inside where it is supposed to connect to the other 2 passageways
you simply can't clean it and have to rely on chemical cleaners and such
to do that for you and they just don't work that good.
that is where the ultrasonic cleaner comes in at it is supposed to clean those impossible to reach areas......( i'll believe it when I see it)
...i'm old school and if I can't poke a wire through it i don't think it's clean ! HAHAHAHA
but these carbs have an area where you can't poke a wire through it
.... I even straightened out a small spring so it would go around corners in there but that only gave me limited success !
the best answer is Ducattiman !!!
and I am seriously considering pulling my carbs off and sending them to him because I just don't want to mess with those things again !
....
Bob......

February 5th, 2022, 01:49 AM	#32
Bob KellyIII Retired motorcycle Mc. Name: Robert Location: Weed, California. Join Date: Jul 2021 Motorcycle(s): 2012 Kawasaki Ninja 250R, 2021 CSC TT250, 1977 Triumph Bonneville 750cc,2001 Honda XR650L. Posts: A lot.	a quicker easier check would be just cover the throat of the carb with your hand and see if that cylinder picks up.... that is if you have the air box off and can reach it.... stuff is so close on a ninja it makes even simple tests like that dificult.... LOL of course that will depend on if you have fuel reaching that carburator too because if that carb is dry that won't change a thing ! but if it's running on one cylinder and you put your hand over the other carb and it picks up that cylinder too then you found the problem it's just not getting fuel through the carb....for what ever reason .... incidently, the cylinder that was not firing on my bike was wet as it could be and it did look like oil too running on one cylinder will pump oil in the dead cylinder because it is not firing , I changed the plugs in my bike as well just to be sure and it still would not fire ... I had the boots off the air cleaner side and could reach down and cover the throat of the carb carefully with 2 fingers and that cylinder immediately fired up ! I thought AH HA !!! no fuel ! because the choking of that side made it much richer and it fired up ! that told me it wasn't getting fuel at idle ! I played with it for a few days because I dreaded taking the carbs off one more time ... so I got the idea of adjusting out the air screws a little more and soon as I did that she started to run on both cylinders at idle ..which it had never done that before ! ..... but unfortunately 3 months later it is doing the same thing again dropping to 1 cylinder at idle.... so I really need to pull the carbs and clean then again ! ..... the problem with cleaning these carbs is you cannot get into ALL the passage ways on the idle curcuit with anything.... I even bought a carb cleaning tool off Amazon and it worked great but it is useless at cleaning the crossover area deep inside where it is supposed to connect to the other 2 passageways you simply can't clean it and have to rely on chemical cleaners and such to do that for you and they just don't work that good. that is where the ultrasonic cleaner comes in at it is supposed to clean those impossible to reach areas......( i'll believe it when I see it) ...i'm old school and if I can't poke a wire through it i don't think it's clean ! HAHAHAHA but these carbs have an area where you can't poke a wire through it .... I even straightened out a small spring so it would go around corners in there but that only gave me limited success ! the best answer is Ducattiman !!! and I am seriously considering pulling my carbs off and sending them to him because I just don't want to mess with those things again ! .... Bob...... __________________________________________________ Its too late when you've gone too far !