Bogged down below 6krpm

[CJLowton]

I have fixed this issue but thought that i would share the tail for anyone that may experience the same issue...

So the story begins....After the Zaks rest over winter i noticed that on most days he was 'Turd' to say the least when pulling away, but when the revs came up was back to normal 140mph+, this happened 4 times out of 5. I put up with this until last thursday, obviously reading the forum i thought that the carbs needed cleaning, being a wus i called in a mechanic to do this for me, he cleaned the jets, 1 blocked - put the bike back together but it still kept dropping onto 3 cylinders, damn it! so £140 quid down and bike still sh*t, starting to get pi~#ed off now...

Mechanic had a play then we noticed that there was fuel pis#ing out of the carbs a couple of seconds after it dropped onto 3 cylinders, Rodz - the mechanic informed me that this was flooding and that the float needles\valves needed to be replaced - (i might add that during the strip down Rodz pointed out that these were very worn). Rodz instucted me on how to fit these parts so i could save some cash.

So parts ordered, arrived a couple of days later, fitted and bike was worse??? Still running on 3 but now turd all the way through the rev range, topped out at 110mph so now not happy at all, give Rodz another call 'HELP' he said replace the sparks as flooding could have screwed my new spark plugs, more money!

Currently at £220 - £140 carb clean - £50 float needle\valves - £30 - spark plugs.

Guess what...no difference.
At this point i feel like parting ways with the bike, Rodz thought that it could be a ignition coil as there was alot of corrosion on the connections, my friend has a ZXR so I thought pinch his to prove this before i buy more parts, but before i did this i thought 1 last strip and see if i can see something stupid...

Low and behold i found the issue that i am shamed to admit but will be usefull for everyone to know.....
while i replaced the needles\valves i STUPIDLY out one of the floats in upside down! IDIOT!

Moral of the story take your time with carbs lol!

Bike is now super fast and revy....

[parby81]

If it makes you feel better, I put the needle assembly in the wrong way round before!! Rev'd fine the first time but once the needle was out it couldn't return and so was absolute pants below 4k revs. Glad you got it sorted in the end, enjoy the summer (even if it is overcast)

[cargo]

It has been my considered opinion for some time now that a substantial percentage of the ZXR400 problem we read about on here are due to "user error"

And to stay on the theme of carbs the rubber o rings in the float valve seat can cause flooding too if they are old and cracked

[Tirpitz]

It has been my considered opinion for some time now that a substantial percentage of the ZXR400 problem we read about on here are due to "user error"

+1

And a good deal of the remaining percentage due to poor maintenance / abuse

Mr Kwak really does make a very robust and reliable machine, if looked after.