Z1OwnersClub GB

Had the Old girl out for the first time today only to return with the following problem, The bike runs ok up to 5000 rpm then it has an unwillingness to rev with a missfire / popping and will not run cleanly through the rev range. For background info the bike has had brand new Dyna S Ignition new coils, new leads and new Denso plugs. The two left hand exhaust pipes have blued on this short journey more so on no1 cylinder.
My first thought is could I have some faulty plugs so I have replaced them with the NGKs that were in the bike last year {I only changed them as so many recomend them here}. I don't think it is an air leak as the carb's have not been touched although I have rechecked all the clips are tight.
Any thoughts would help as I am at a loss where to start. After spending so much on the ignition I am a little fed up as I was expecting the bike to run sweet this year.

Hi Alan,

First thoughts are fuel, is it the fuel thats stood in the tank all winter? Has it gone off?
Did you drain the carbs, or start the bike every now and then, has the fuel evaporated in the carbs and left crud in the jets?
Modern fuels do seem to cause some probs if left for a while.
Was it running ok before you laid it up and was that with the Dyna etc fitted? If so and nothing else has changed then fuel gone off seems the most likely option.

The Dyna S was fitted over the winter after the original Newtronics system failed. Proir to above the bike ran well.
I thought I had drained the carb's however I have now found this to be incorrect {to much shit going on at work and I must have forgot}
If as you suggest the fuel went bad what's the remedy.
I hae replaced the plugs with no improvement so I think I can rule out a faulty spark plug

Hi Alan, hopefully worth trying some fresh petrol first, but may be carbs will have to come apart for a clean.

One other thought did you get the right Dyna for your advance unit if I remember there are 2 different types, having said that the coils power 1 and 3 and 2 and 4 so if 1 and 2 are blueing that kind of rules out an ignition problem I think.

I have filled the tank with fresh fuel with no real improvement.
The Dyna was from Jeff at z1 enterprizes after I e.mailed him a photo of the advance / retard unit so I am confident it is the correct one.

I have all the Dyna gear on that you have and its good makes it better to start etc. Did have plenty of problems timing it up in the first place though turned out to be a faulty unit.

Since the ignition is the only thing thats changed, really it and the fuel are the only 2 poss.

If you are sure its timed properly and the advance is working , easily seen with a stobe; then my best guess is the fuel has evaporated and left something in the carb jets, BUT before you start ripping them apart we could do with some more input from someone who really knows what they are talking about?
Also is it fuel starvation caused by a blocked fuel filter or blocked breather hole on the fuel cap?
( I would also e mail Jeff and see what he thinks, there is a tech link on their web site and they are very helpfull.)

What's the fuel feed to lhs carbs like? check for kinks in the pipe as well if it is separate from the rhs.

Steve R wrote:Hi Alan, hopefully worth trying some fresh petrol first, but may be carbs will have to come apart for a clean.

One other thought did you get the right Dyna for your advance unit if I remember there are 2 different types, having said that the coils power 1 and 3 and 2 and 4 so if 1 and 2 are blueing that kind of rules out an ignition problem I think.

one coil powers 1 and 4 and the other coil powers 2 and 3 .

Im sure it was just a miss print steve R

It does sound like fuel problems though, though maybe worth double checking the rotor as below.
http://www.z1enterprises.com/detail.aspx?ID=200

No Floyd I was wrong I just knew 1 coil didnt power 1 and 2 together!

i understand what your saying now steve, ive had a long day,

Alan,
what exhaust have you got, could be that if its a 4 into 1 it could be single skinned so probably all the pipes will blue, maybe its that the right side ones are not getting hot enough yet because its that side, 3 and 4 thats not running properly.
first i would check that the carbs are clean and have fresh fuel, you can get a carb cleaner that you can put in the tank (and then run the engine) but not sure how good it is, maybe worth a try before stripping the carbs.

good luck, hope you get it sorted now the weathers getting better.
peter.

I think someone already made the best guess.... only thing in common on 1 & 2 is fuel supply. Got to be worth checking the flow . Is there a partial blockage on either the tap or maybe an in-line fuel filter or a kinked pipe even.

When you try to run it faster than 5,000 and it won't pull, does it recover instantly when you throttle back, or take a short while at smaller throttle before it will pull cleanly again ?

Sounds like shit/dodgy fuel in carbs.
Was bike left on side stand? Fuel will stay in #1 longest, then #2, .. 3, 4

I'd rinse tank out with new fuel & drain carbs first. Sounds like main jets are gummed/blocked up

I'd forget ignition issues first & do fuel checks.

Any mice in air box

After I rebuilt my carbs I had a misfire at 5k which turned out to be the main jet which had fallen out

I must have used Pigfords tools on that one