Z900-A4 engine issue

[Paul Whitehouse]

Hi guys,

Just wondering if any of you could shed some light, or point me in the right direction for an engine issue that's got me stumped.

My Z900-A4 started playing up while riding back from Dijon last year. I've only just started to spend some time looking at the issue as I've been riding and concentrating on my Z1000. The bike is fitted with a 4-1 exhaust, bell mouths and carbs have been re-jetted accordingly...this setup has been on the bike for years, running really well, and never had any problems.


The bike will start up fine and idle ok. When I blip the throttle, which is very responsive, the revs are very slow to return to idle. If I attempt to ride the bike the issue continues and when I close the throttle I have very little engine breaking. My first thoughts were that I had an air leak so areas tackled so far have been:

Carbs removed and cleaned. Jets cleaned and checked.
New carb inlet rubbers fitted.
Airscrews seated and back to factory settings.
Carbs balanced and set up using vacuum guages.


But the issue still not sorted...any suggestions of other areas that I can start to have a look at gratefully received...


Cheers,


Paul

[zed1015]

Simple things first off the top of my head.
Check for sticking/frayed throttle cables, not enough slack or binding throttle grip.
Ignition advancer sticking /springs stretched.
Valve clearances closed up.

[Paul Whitehouse]

Cheers Rob, i’ll start to check these this afternoon.