ZZR-1100 Advice

[Alf Stewart]

Started, ran at about 2500rpm with full choke for a bit, now won't run. Probably need take carbs somewhere for a fancy clean. Think the problem is fuel struggling to get through. Probably a partial blockage or something, I'll try run it off a bottle of fuel tomorrow to see if that makes a difference at all. Worried I may need to clean carbs yet again

[MichaelZZR]

Hi all, a very interesting thread. I purchased a ZZR1100 in 2014. The bike was in great standard condition and had only covered a genuine 20,000km from new. It had been laid up for long periods of time.
The problems I had were:
Fuel Pump gave up soon after I got the bike
Coolant hose split. On inspection all the hoses looked great on the outside but were all perished internally
All fuel pipes were likewise stiff and split easily
Caliper pistons were semi seized
Fork oil resembled soup
A majority of the seals in the carbs, engine were not doing their jobs
Carbs hopelessly out of sinc
Cush drive was intact but when compared to a new one was very hard
Handle bar controls. Switches had become brittle inside and broke
The seals in the fuel tap and even the fuel cap were not sealing
Just about every electrical connection needed cleaning
Rear shock was not at its best
All suspension linkages had not seen any grease
A semi seized caliper piston had, it would seem, caused a disk to become warped. Not really noticeable at town speeds but pulsing at high speed(or maybe some clown had just damaged it)

All of the above were replaced with parts from Kawasaki but it taught me that even a bike that looks great can have many hidden faults if it has been left idle for long periods of time.

[Alf Stewart]

This bike is borderline ready for a match...

Got it running off a bottle of fuel and tank, starts with full choke, idle screw backed all the way off.
Can back the choke off so far, will rev with a flat spot here and there (no air box on ATM).
Seems once it gets a bit warm it gives up. I'm still suspecting fuel is the issue.

I noticed it had lost spark to cyl 1, and then discovered how the plug leads are set up on these, trimmed a little off and redid the plug caps, good spark on all 4 now.

I'm probably going to give the carbs another clean, not happy with my first attempt, think i may need to replace jets, still looked shabby after first clean.

Need to re read thread to check what you have all suggested. Should I reset the pilot screws to factory setting? I didn't want to fiddle with them last time. Worth spraying carb cleaner down the hole when I have them removed?

At a bit of a loss. Oh on a side note, noticed the fuel pump gets stupid hot.....

Cheers.

[Alf Stewart]

Just had the carbs apart again, feeling more confident with the quality of the clean this time.

The pilot screws were all set from 2 and 1/16 through to 2 and 1/4 turns out. Have reset them all at 2 turns out as per manual. Unsure if that amount makes much of a difference.

Noticed there are 2 washers on each of the needles, didn't think nothing of them last time but just realised these may be shims? What effect will they have? Should I remove or do I need to adjust something to compensate?

About to put carbs back on the bike so with any luck it decides to play nice and come to life.

[Mister_T]

Should I reset the pilot screws to factory setting? I didn't want to fiddle with them last time.

A quarter of a turn should not make much difference unless everything else is spot on.

Worth spraying carb cleaner down the hole when I have them removed?

Through all the holes would be standard procedure during a carby clean, perhaps using compressed air as well if available.

Oh on a side note, noticed the fuel pump gets stupid hot.....

That sounds like a clue. The pump should not have to work hard at all. The flow required is small and the pressure required is small.
I wonder whether the pump is overheating and cutting out. As to why it might be overheating is something else. A restriction somewhere?
Is there some sort of fuel return system?

I once diagnosed a temperature sensitive restriction in the injector rails of a car. It eventually required 2 pressure gauges and some T-pieces and some extra hose to prove it.

[Mister_T]

Noticed there are 2 washers on each of the needles, didn't think nothing of them last time but just realised these may be shims? What effect will they have? Should I remove or do I need to adjust something to compensate?

The FSM should show where these washers go. My guess is that there might be one washer on the each end of the spring.
There should no need to be any compensation. It still comes down to how many turns out from the needle being fully seated.
One reason for one of the washers would be to protect the pilot screw's sealing O-ring from the spring.

[Alf Stewart]

Unsure on the pump, i think it was having issues drawing fuel from the tank, i have ran a fuel line from the intank filter to the fuel cock as i suspect the intank line is particularly blocked. Didnt have anything to poke through it so thats a job for another day. None the less the pump is no longer over heating

Cleaned the carbs much better this time. Put a tube on the spray can and got cleaner down every hole i could fine, each time it would spray out from somewhere else so confident the galleries are all clear.

Im 99% certain the pilot jets are no good. The main jets look ok, and the main jet holders look partially blocked and worn. Dont have compressed air handy which doesnt help but have decided im going to replace all the jets and holders, sent an email off this morning to a local supplier.

Bike now starts without hesitation and responds to choke well and will take some throttle input. All the cylinders appear to be heating at the same rate now. So with any luck it will be all good once i do the jets.

Will still be a long list of things to do but at least i will be able to ride the damn thing.

[Alf Stewart]

Going to have one more go at cleaning the jets, new ones are a lot more pricey then i thought.

Some one has suggested i try 'Threebond super engine conditioner', give them a spray, soak for a good half hour, wash in water. Supposed to bring them up like new if i use a toothbrush. Sound about right or am i wasting my time if im not using a compressor?

[Mister_T]

Im 99% certain the pilot jets are no good.

The pilot system blocks the easist. It flows the least fuel and air so the holes are small.

The main jets look ok, and the main jet holders look partially blocked and worn.

The main jet holders have small holes along their length which allows the fuel from the main jet to premix with some air before it gets out to the carby bore. The small holes can block up with stale fuel. You can use wire to unblock the holes if you are careful.

Bike now starts without hesitation and responds to choke well and will take some throttle input. All the cylinders appear to be heating at the same rate now. So with any luck it will be all good once i do the jets.

Getting somewhere.

Will still be a long list of things to do but at least i will be able to ride the damn thing.

I know the feeling.

[Alf Stewart]

One last attempt at cleaning, likely tomorrow night, and if that fails I've found an Australian supplier of Keyster rebuild kits.

Kit comes with main jet, pilot jet, main jet holder, float needle and chamber, gaskets, orings and a few other bits. At $35 a carb i think it's a good buy. Considering the best price I've found for the holders alone is $40....

[Mister_T]

Going to have one more go at cleaning the jets, new ones are a lot more pricey then i thought.

Yes, there is some precision machining there.

Some one has suggested i try 'Threebond super engine conditioner', give them a spray, soak for a good half hour, wash in water. Supposed to bring them up like new if i use a toothbrush. Sound about right or am i wasting my time if im not using a compressor?

Use whatever you can get to clean the brass, whether it is Shellite, X55, paint thinner, turps, metho etc. As long as it does not eat the metals copper and zinc that make up brass then it is fair game.
Come to think of it, sport shooters who reload their own ammo should have some commercial brass cleaning products available to them. I guess ultrasonic baths, either commercial or home made, have replaced many of the nastier chemicals used in the past.

[Mister_T]

One last attempt at cleaning, likely tomorrow night, and if that fails I've found an Australian supplier of Keyster rebuild kits.
Kit comes with main jet, pilot jet, main jet holder, float needle and chamber, gaskets, orings and a few other bits. At $35 a carb i think it's a good buy. Considering the best price I've found for the holders alone is $40....

Haven't heard of those but I have been away from bikes for a while.
Hopefully the jets are the same size as yours. The kits may be originally intended for some other larger market (e.g. USA) which may have had slightly different jetting.

[Alf Stewart]

Checked the jet sizing, they are exactly the same as what is in my bike and as the manual says. It is an american product as you say. Will pick something up today and clean again tonight. Hopefully ill have some good news at the end of today.

Its just started raining here which is a shame, will have to wait till its dry for a proper road rest.

[Alf Stewart]

*double post*

[Alf Stewart]

So, I have good news and bad news.....

Got all the jets clear, reinstalled and assembled. It lives!!!

Took the bike for a road test, had to use some choke, assume because still warming up, got to the top of my street and died, fiddle with choke a bit, got it going. Half way around the block, died again, starting fiddling but started to rain so rolled around the corner and pushed it back into my driveway. Started with choke, started to wind in the idle adjustment screw, back off choke, adjust screw, back off choke and so on. Got it idling with no choke, set it around about 1000-1050rpm, was revving freely and returning to idle beautiful. Didn't get to take it for another lap due to the rain and what not. And then suddenly wouldn't accept any throttle, just die. I may or may not have tweeked the idle setting a tad but a fraction of a turn at most. Better not have sucked some shit into the pilots haha.

I'm thinking I may need to adjust the pilot screws on the carbs? I reset them all to 2 turns out as per manual. I checked the, before setting and they varied from 2 through to 2 and a 1/4 turns out. Possible this is my issue? How do I determine if it is running rich or lean? Little stumped as to why it revved great, then not at all.

Any suggestions greatly appreciated. You have all been very helpful so far. Cheers.