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asda160

Joined:

Jun 09

Posts: 9

asda160 says:

zzr1100 rougher than a rough thing

Hello,

I've got a 99 zzr1100 d7 with 19k on clock with a rough idle:blink: with or without airbox that i can't cure...what has been done checked is as follows..valves rechecked (done at 18k), carbs serviced & balanced and mixture set using co meter, new o rings on intake stubs and checks for intake leaks done with carb cleaner...coils and leads, caps and pickup checked against oe figures for resistance and are in tolerance, compression checked and all four very similar, voltage at battery checked 14.2v at idle and rises to 14.4 with increased revs, new plugs, coils swapped around but when idling if i pull No2 plug lead there is little difference in engine note...the spark is there but looks weaker than the rest...so i turned to the CDI...has anyone had this type of problem and found it to be this unit...i've tried checking with a multimeter with two of the checks giving no reading at all..but surely it would cause probs higher up the rev range..but once past 3k it pulls like train...is there anything i've missed that would cause this symptom..or has anyone got a known to be good cdi in the east mids area that i could try and possibily buy ??...lettuce snow:biggrin:

Dave

 

P.S..it's as standard as a standard thing including the jets in der carbs

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  • Posted 6 years ago (03 July 2009 15:04)

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kcmc

Joined:

Jan 08

Posts: 7721

kcmc says:

With all the work you have had done

You will understand that i to am a bit clutching at straws!!So first thing to check,drain float bowls into a clean container to see if the is any water or debris.Now i know you are going to think,no way but the water or contaminant could be it the fuel tank contaminating the carbs after cleaning.Check the fuel pump relay and the in-line filter from the pump.Check the air gap between the pulse sensor and rotor(sorry don't know what it is at this moment in time)Can't remember if the coils are only one low tension live in?but if they are make sure they are well earthed.Pull ever electrical connector and check for corrosion. Good Luck

Hope you haven't an alarm fitted :shock: 

K.C.  

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m1ks

Joined:

Apr 09

Posts: 908

m1ks says:

.

You've covered near enough the main things i'd suggest to check.
Theres one thing I guarantee you won't have thought of though, (I never would if I hadn't done the same as you then discovered it myself)
A few years ago I had a ZZR250 and a rough and unreliable idle was a problem, revs fine higher up.
You'll have a sidestand switch which cuts the engine if you engage gear with the stand down, these over the years are prone to all manner of abuse from drips of oil and fluids to salt, road crap water, mud and who knows what else, (this applies to all makes not just Kawasaki BTW)
If you trace the two wires from the switch on the stand it will go to a block connector, (generally somewhere around the underseat or under a sidepanel), or a couple of bullet connectors, which in turn feeds into the loom, unclip that and you'll lose the engine cut out when engaging gear with stand down but it'll show immediately if this is the cause of your problem. If bullet connectors you may have to reconnect the loom end connectors together for it to start and run, depends if it's a make or break connector.
I swore profusely when my ZZR purred like a kitten after doing this, (this of course being after i'd gone through the same kind of scenario as you including fitting new HT leads)
If it is this, your options are get a replacement switch and make sure it's well protected from crud or leave it unplugged, I just unplug (or short as appropriate) them as a matter of course now.

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asda160

Joined:

Jun 09

Posts: 9

asda160 says:

more work to be done yet me thinks

Guys thanks for the replies....it's driving me insane:mad:

KC..i thought about the fuel so bought a can and made a make shift fuel tank..carbs have been stripped, float levels checked ..only no4 carb was out.

i started pulling all connectors..i must ave read your mind....i have found wiring for an alarm which the previous owner had hidden with 18 miles of black tape...this has all been removed and where they tapped into the loom soldered properly and covered in heat shrink.

M1KS..nice one...side stand wire...had not even crossed my mind...will do it straight away...but why would it make just one spark weak...anyhow gonna do it just cos...everthing else has been apart :laugh:

SMIDGET...yep hear what your saying...i have swapped leads around and caps around and coils around and plugs around..always No2 cyl that is at faultbut the leads are copper and do come below the ohm range ....the caps are a tadge under 5ohms..is that a lot ?..i'm not sure as there is no data for just the caps..the test is done without the caps on.

Agains thanks for the techy type support and ideas

Dave.

[This Reply has been modified by the Author]

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asda160

Joined:

Jun 09

Posts: 9

asda160 says:

still struggling

:mad:  help..cant sort it..side stand switch isolated..still same..80 big ones spent on known good cdi ..still same, that was after i blew the diodes in my junction box when removing  alarm wiring, leaving me with no spark..nuther £20 squid..., clutch switch eliminated and still same...has anyone tested coils and leads and found them to be in spec but upon changing cured a low rev  misfire...damn thing..and the weather is so nice too:upset:

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m1ks

Joined:

Apr 09

Posts: 908

m1ks says:

.

Theres no reason why only cylinder 2's spark would be weaker, one coil feeds two cylinders, 1 and 4 and 2 and 3 respectively.
On what's known as a wasted spark system, it fires even on the exhaust stroke.
If swapping the leads round doesn't change the problem to cylinder 3 or alternatively changing the coils around doesn't change the problem to another cylinder then the problem isn't there.
I'd try a compression check to ensure all's as expected, Valves are OK clearance wise but a bent valve not sealing causing low compression is a possibility

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kcmc

Joined:

Jan 08

Posts: 7721

kcmc says:

STILL

Dirty carbs.

Get someone else to clean the carbs,or replace them with a good clean set.

K.C.

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asda160

Joined:

Jun 09

Posts: 9

asda160 says:

nearly there

it's me again..just a quick reply so's you don't think i'm ignorant.....

to cover a few of the comments made....compression is within spec although at the lower end 135 to 150 psi across all four cylinders.

The low range misfire..i have cured after a long conversation with an auto electrician who highlighted that testing coils is performed at a specific ambient temperature, which cannot always be replicated...so two brand new coils and bingo.....point of this matter is the originals showed within spec...:huh:

however i still have the erratic tickover which i do need further assistance with..

Now there was mention of a bent valve...would this not show up in a compression check or could this be why it's at the lower end of the scale

the rubbers are good..when i spray easy start or similar around there is no rev increase....the mixture screws set to factory....carbs balanced after being cleaned out again and float heights checked and checked with clear tube from carb drain.......but what i can see at tickover is small droplets of fuel leaving the main jet's....now is this float height or worn needle and jet...or weak diagphram's allowing needle lift.....

Thanks again....

Just L:upset::upset:king :upset:utside and it;s sunny and i'm stuck with me bike in bits....:mad:

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m1ks

Joined:

Apr 09

Posts: 908

m1ks says:

.

Now that's interesting, i'm assuming you're looking through the intake with the airbox removed?
Diaprhagms is something i'd forgotten to mention.
The rubbers can get worn and get pinholes in them, whip the carb tops off  and check each, any that are holed will need replacing as this will create a popping effect due to pressure build up and release.
While you're at it check that the needles are all straight and in the correct clips.
Good to hear you got the coils sorted, they are a bugger to assess correctly as you AE said they work differently according to temp and load and your basic haynes book testing can only give you a basic idea, they often break down under load and heat giving rougher running and misfires after warming up.

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asda160

Joined:

Jun 09

Posts: 9

asda160 says:

and finally ..a liquid decoke

Just so's you dont tink i is rude...found the problem eventually...the valve thing might not have been far off....when i looked in through the inlet ports it looked quite coked up so...three cans of redex over a period off two days ...the oldies amongst us will remember this trick and all the tar/gum forced out by compression through the plug holes then the excess redex burnt off by running the engine..loadsa white smoke :lol:..then an oil change in case any redex has slipped past rings and voila ...a smooth tickover....thanks for your assistance   Dave

[This Reply has been modified by the Author]

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gdiband

Joined:

May 07

Posts: 5

gdiband says:

Rogher

Hi. Did this really work? I am at my wits end with the same problem changing things like coils and everthing mentioned above with no success. How did you use the redex did you put it in the fuel or didi you pour it neat into the cylinders/

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