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hciR wrote:There's some info about revs hanging here: viewtopic.php?f=7&t=8088&p=64855&hilit= ... ing#p64855
The screws are on the under side of the carbs (as they sit on the bike) you will need to take the carbs off. I turned mine about 2.5 turns from fully wound in, iirc the manual says 2.75 for a H moddel but I think it's less for an L. Either way a bit of trial and error might be in order, I just turned them out by half a turn from where they were originally.

If you can do them in situe:

Once the bike is fully warm, screw them in until you hear the bike starting to run bad (1 at a time) , then slowly wind it back out until you hear the rev's catch again.

Do this for each one and give the bike a good couple of hand fulls and see how stable it is - not perfect by no means but as you lean the mixture the rev's drop so bringing it back slowly you can catch the point where the air/fuel works best for your set-up.

Clean the end of your can and go for a 20 mile ride, include stop start, high speed and cruise.

When you get back to base your looking for dry black soot on the end - if it's brown the screws need to come out a bit more to richen it , if it's wet your too rich so they need to go in a tad.

Generally not all the air screws are set the same, you'll find that say for example setting them all at 2 3/4 turns out that the tickover is erratic but a small tweak on a couple might level it out (no more than an 1/8th turn)
When doing the ZRX I took my screwdriver with me and hammered it along some straights until i was happy about pick-up and no flat spots. went into the garage got the sniffer on it and it was a bit rich (no bad thing) and they just tweaked them a bit. But still think my settings were better lol

Haven't had a look recently but I am sure with a small screwdriver you can do this with out removing carbs.

Legends! WIll try this out ASAP! Cheers!

mmmmm wished id known this when i had my zxr750

Bike looks mint, needs a rear hugger though.

Cheers, I do have a hugger but it was sprayed blue and is a bit of a state. I either want a carbon one or will spray the one I have black.

Just updated my post as sometimes I type what I am thinking and not what I have just thought, doh!

IMPORTANT:

Air mixture screws being turned in LEAN the mixture

Air mixture screws being turned out RICHEN the mixture

Always err on a RICH mixture, the can will become sooty very rapid and you'll notice a drop in fuel consumption. If that happens you know to turn them in an 1/8th max to see if that helps.

Just to calrify, these are the screws on the little stump bits at the bottom of my carbs?

Scott221 wrote:Just to calrify, these are the screws on the little stump bits at the bottom of my carbs?

Yip, just before the inlet stubs you'll see them sitting in tubes/stumps/tunnels off centre of your carb.

Sorry i don't have a pic' just now but between cylinder head and float bowl.

Off to Motegi tomorrow but if your needing clarification not a problem to do some photos by Thursday - got a set in the cupboard.

Managed to find a pic

Will have a play with this tomoz. thanks very much!

Ok, going back to this. After 240 miles of blasting it about over the weekend. I came home and the tip of my can is covered in black soot. Its not wet and its not brown. So i take it my fueling is spot on? Why then do my revs hang so badly?

Also, when cold and starting the bike, it will start, run fine for 10 seconds and then cutout, it will not start again without using choke, acting like its flooded. Also, the bike struggles to pull away from low revs, it really bogs down and takes off at 4k.

Any ideas?

Hi S,

Don't know if your the original owner of the bike, either way have the carb's been messed about with in the past?

I would check your float valve heights, could be your bowls aren't filling up enough and the bike is fuel deficient at times.

can't say your fuelling is spot on with out an air fuel check but your can certainly indicates it's in a good place

Other things to check (with your re-build) is air leaks - this can be before the carb's , between the carb's & head and the headers into head.

If your pipe is loud and with the bodywork on, it can be hard to hear a blowing header.

Go round and check the "fastness" of the clips onto the carb's and the exhaust flange nuts.

Also, how old are your plugs? never rule them out even when new - believe me, I had a new set out of the box never fire up the bike - plugs go "off" when sitting and I reckon the shop had had them for ages.

Putting new iridium's into my own bike as it has started to develope running problems all of a sudden !

MM!