X9 Owners & Riders Club

Other Bikes and Scooters => Bike Fettlers Shed => Topic started by: wardy_uk1 on July 13, 2011, 19:53:09



Title: Kawasaki Zephyr 550
Post by: wardy_uk1 on July 13, 2011, 19:53:09
Hi guys. My dad has a Kawasaki Zephyr 550 that I'm eyeing up as my next bike  :whistle:

Anyway, the problem is when it starts up the revs sometimes go straight between 4000-5000RPM. Other times when it starts the bike struggles to get to 1000RPM then it stalls. We have cleaned all 4 carbs out but still does the same.

Does anyone know what else we can try. Cheers


Title: Re: Kawasaki Zephyr 550
Post by: Dave Milnes on July 13, 2011, 20:33:52
Any engine with carbs that revs higher than the throttle is open, has a bad air leak between the carbs and the cylinder head.
Start there. Look for cracks or loose clamps or a duff gasket between manifold and head.
The carbs need manifold depression (vacuum) to lift the fuel metering needles so if the manifold is not air tight the response is not consistent.


Title: Re: Kawasaki Zephyr 550
Post by: wardy_uk1 on July 14, 2011, 17:17:22
Thanks Dave for the reply. We've just had a good luck but cant't see anything wrong. We left the main jets soaking in clean petrol overnight to clear the holes. Went to use a fine needle but can't get it through the holes. Could the main jets be the cause?    :unsure:


Title: Re: Kawasaki Zephyr 550
Post by: Dave Milnes on July 14, 2011, 18:58:07
Possibly. compressed air is best as shoving needles through can scratch them, and they are precision holes, every scratch counts towards a worn jet.


Title: Re: Kawasaki Zephyr 550
Post by: wardy_uk1 on July 14, 2011, 19:49:43
Is this the same for the pilot jets?


Title: Re: Kawasaki Zephyr 550
Post by: Dave Milnes on July 15, 2011, 10:30:08
Any brass jet as it is a sof material.
Has it been sitting dry for a while?
Sounds like plenty of redex or similar might be an idea when you next get it going. That will shift all carbon deposits and general build up of dirt. You can use it neat through the spark plug hole to clean the rings and valves as well as adding it to the fuel for the first tank or so.
Diesel also works well as a cleaner used to soak parts in that have got rather encrusted. Don't add it to your fuel though!


Title: Re: Kawasaki Zephyr 550
Post by: x9500 steve on July 15, 2011, 15:48:18
I have found silkolene PRO FST is excellent for curing these kind of problems providing there are no air leaks  :)