ninjette.org - View Single Post - Both my baby 07’s are sick – Hitting a 4-6k rev wall

Bob KellyIII · March 28th, 2023, 05:42 PM

I say forget the Jet Kit completely because unless you did a major bore job and replaced the exhaust system the jets will just mess you up ! the reason to change the jets is to get the plug color correct..... no other reason it really isn't a HOP-UP for the bike getting the burn correct IS a hop-up !
normially the Ninja's are jetted fairly lean so changing by 1/2 a jet size to 1 jet size is ok and will make it burn better but throwing in a jet kit to get it running better/more powerful is a fools game improve the flow YES that is a good hop-up but jetting rarely is.... of corse if you improve the flow you almost always have to re jet, but that's beside the point
.... I think what is going on is your dropping a cylinder at 4k RPM or around there .... check running the bike on a seperate fuel tank so you can see the coils and stuff under that big tank and see if your getting arching anywhere
colder damp weather can bring that out... perhaps you have hard water that has left deposits on the spark plug leads that cause arching... i've seen that before, a guy I knew pressure washed his bike and he could only get it to idle
after that... I came over to give him a hand and it was late evening and sure enough it would not go above idle, the sound changed but that was all ...I bent down and looked under his tank where the coils were and saw a light show when he tried to give it throttle.... he popped the tank off and spreyed the leads and connectors with WD40 and then wiped it all off and that was all it took at first it balked at the idea but then it farted and took off !
....
both bikes doing the same thing points to something you did wrong, but what is the question.... did you have to reset the floats ? did you take out the jet needles or change the clip position ? or shim them perhaps
Something you did caused this so search your memory and question everything you did.... is anything new in the system ? new spark plugs ?
maybe that is the culprit ! one failing on each bike would not surprise me at all in my youth I saw 4 out of 5 sparkplugs be bad right out of the box
I would test them by laying then on the head and hitting the starter and they would arch internally not on the tip I went through a period of about 5 to 6 years where buying a good spark plug was a gamble !!! maybe you got a bunch of bad ones ?..
.....
look for a loose vacuum hose before you do anything else because that could/would do it !!!!!
....
good luck
Bob.....

March 28th, 2023, 05:42 PM	#28
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.	I say forget the Jet Kit completely because unless you did a major bore job and replaced the exhaust system the jets will just mess you up ! the reason to change the jets is to get the plug color correct..... no other reason it really isn't a HOP-UP for the bike getting the burn correct IS a hop-up ! normially the Ninja's are jetted fairly lean so changing by 1/2 a jet size to 1 jet size is ok and will make it burn better but throwing in a jet kit to get it running better/more powerful is a fools game improve the flow YES that is a good hop-up but jetting rarely is.... of corse if you improve the flow you almost always have to re jet, but that's beside the point .... I think what is going on is your dropping a cylinder at 4k RPM or around there .... check running the bike on a seperate fuel tank so you can see the coils and stuff under that big tank and see if your getting arching anywhere colder damp weather can bring that out... perhaps you have hard water that has left deposits on the spark plug leads that cause arching... i've seen that before, a guy I knew pressure washed his bike and he could only get it to idle after that... I came over to give him a hand and it was late evening and sure enough it would not go above idle, the sound changed but that was all ...I bent down and looked under his tank where the coils were and saw a light show when he tried to give it throttle.... he popped the tank off and spreyed the leads and connectors with WD40 and then wiped it all off and that was all it took at first it balked at the idea but then it farted and took off ! .... both bikes doing the same thing points to something you did wrong, but what is the question.... did you have to reset the floats ? did you take out the jet needles or change the clip position ? or shim them perhaps Something you did caused this so search your memory and question everything you did.... is anything new in the system ? new spark plugs ? maybe that is the culprit ! one failing on each bike would not surprise me at all in my youth I saw 4 out of 5 sparkplugs be bad right out of the box I would test them by laying then on the head and hitting the starter and they would arch internally not on the tip I went through a period of about 5 to 6 years where buying a good spark plug was a gamble !!! maybe you got a bunch of bad ones ?.. ..... look for a loose vacuum hose before you do anything else because that could/would do it !!!!! .... good luck Bob..... __________________________________________________ Its too late when you've gone too far ! Last futzed with by Bob KellyIII; March 28th, 2023 at 07:05 PM.