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

Bob KellyIII · March 28th, 2023, 09:49 AM

Ok there is this... when I got my carbs back from Ducattiman I had the same problem and I am almost positive that it is simply spark plugs !
but I got off the track, been working on my other bike and haven't got back to it.... as I don't have new spark plugs for it....
I pulled the spark plugs and put them on the trunk of the bike and mixed them up and I think I put an old one back in it.... it was running good taking rpm all the way to 9k with no problem with the choke on before the tear down, I did the valve shims and pulled the spark plugs and put them in the trunk...all 4 plugs got mixed up.
when I got the carbs back I put them back on and I had the same 4K wall you have been getting..... but I think mine is sparkplugs !
.... I do not see HOW your carbs could be dirty or how mine could be as I know Ducattiman worked his majic on them and got them back to stock for me. I trust his work if he says their clean their clean !
....so maybe, just maybe you have bad plugs Or maybe we both have a shorting coil or CDI failure or something....
that 4 K wall is not normal for me ...I've never experienced it on the Ninja before but I have on other twin cylinder bikes.... what tells me it is spark plug is the fact that I got over it once when testing and I got 10k from it and it sounded right ...but only once....
I am going to replace both sparkplugs and try it.... who knows that might be your problem as well.... other wise your guess is as good as mine it's a puzzle !!!!!
it might be possible that it's just the idle air screw adjustment as well both are different settings on my bike and maybe that is causing one cylinder to drop out and hit the wall at 4k RPM the carb sucks constantly through that adjustment screw so if it's too lean it will effect the mixture on the high end !
good luck !
Bob........

March 28th, 2023, 09:49 AM	#9
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.	Ok there is this... when I got my carbs back from Ducattiman I had the same problem and I am almost positive that it is simply spark plugs ! but I got off the track, been working on my other bike and haven't got back to it.... as I don't have new spark plugs for it.... I pulled the spark plugs and put them on the trunk of the bike and mixed them up and I think I put an old one back in it.... it was running good taking rpm all the way to 9k with no problem with the choke on before the tear down, I did the valve shims and pulled the spark plugs and put them in the trunk...all 4 plugs got mixed up. when I got the carbs back I put them back on and I had the same 4K wall you have been getting..... but I think mine is sparkplugs ! .... I do not see HOW your carbs could be dirty or how mine could be as I know Ducattiman worked his majic on them and got them back to stock for me. I trust his work if he says their clean their clean ! ....so maybe, just maybe you have bad plugs Or maybe we both have a shorting coil or CDI failure or something.... that 4 K wall is not normal for me ...I've never experienced it on the Ninja before but I have on other twin cylinder bikes.... what tells me it is spark plug is the fact that I got over it once when testing and I got 10k from it and it sounded right ...but only once.... I am going to replace both sparkplugs and try it.... who knows that might be your problem as well.... other wise your guess is as good as mine it's a puzzle !!!!! it might be possible that it's just the idle air screw adjustment as well both are different settings on my bike and maybe that is causing one cylinder to drop out and hit the wall at 4k RPM the carb sucks constantly through that adjustment screw so if it's too lean it will effect the mixture on the high end ! good luck ! Bob........ __________________________________________________ Its too late when you've gone too far !