Z1OwnersClub GB

Got a slight problem with the A4 at the moment which im struggling to solve.
All of a sudden its started running rough, stalling on tickover, eratic tickover, and even the odd backfire.
I've renewed all plugs and they have a spark, so that's ruled them out. I'm now thinking carbs, and do i take them off and inspect everything.
All the points and condensors were new on the build, so they should be ok. Any suggestions chaps????.

P.S. nothing to do with this bike, but im after a set of z9 pistons, apart from Z Power, does anyone have some good recommendations. (1mm over). paul

For pistons try Chris Tombleson at Grumpy 1260.

...No quick fix,just a matter of elemination,99% of carb probs are electrical in my view.if it was running fine may be just some crap in the carbs though,had Gs a bit ago and it was the ethanol eating the fuel lines from the inside and dumping it in the carbs.Just cause point and condensors are new dont rule them out,make sure bike is charging at a good 14.5 v or there abouts plus battery good,coils and plug caps and leads,not using Ngk plugs? loads of crappy Chinese copies out there,fuel fresh and flowing well?ignition timing not slipped and advancing correctly?Fuel cap breather clear...Good luck...

Leads, caps etc all new. NGK B8s.
Got the bike hooked up to an auxiliary tank at present as I was about to try and balance the carbs. I'll 're check the timing though.

Does the rough running occur from cold, or when hot? If hot, it could be running too rich. are the plugs sooty? Are all exhaust headers hot after a minute or so of running ? (wear a glove for this please!!) If they are it is probably a carb issue.

Imd pistons I have their rings in my a1, no problems.

If it's suddenly start ed to behave like this it's lees likely to be the carbs and be electrical. I'd check all the obvious, plugs, points, leads, air leaks, air filter, header nuts. If that doesn't throw anything up then get the crabs out and check them over. It's amazing what a few specs of crap can do.
Hope you get it sorted.

Any further suggestions on this one chaps. I thought I'd cracked it. New set of plugs, a fully charged battery and she run fine. A good 20 mile run the other week and no problems. A week later and took it out tonight , and back to normal, its like its on 3 plugs again, coughing and spluttering under load. Surly can't be a plug problem. Startsand ticks over ok, its when you set off. Very strange------

As someone has already said there are an awful lot of fake NGK plugs out there at the moment, so just because they are new.....?

It might be a loose battery lead this happened to me before, and it will run rough

Hi Wrigers
are the ignition coils firmly bolted to the frame? Do they have a good ground? If not, this could be the problem...
Good luck
GrtZ
Philippe

I'll look into that one Philippe.

On my Lawson race rep one coil came loose and was hanging off, it started and reved just fine but backfired through the carbs when ridden under load ( when I opened the throttle).

Well I think I might have cracked it. After removing all the plugs they were all dry and slightly sooty apart from n01 cylinder which was a bit wet.
4 new plugs... NGK B8HS all was well. I think it was running a bit rich on n01 which may have knackered the plug, plus it was slightly Smokey on n01 exhaust as well. I've adjusted the air screw slightly, been out for a good run and so far so good. Here's hoping. Thanks for all the advice by the way !!!

I have been experiencing all the same problems so I will check as advised.

Here's the thing. On most carbs if I wind the air screw in or out there is as expected a notable change.

However I noticed on number 1 that I can remove the air jet and screw it all the way home and it doesn't change.

So I'm guessing its getting its air from elsewhere right and maybe a leak?