ZZR rev-pick-up problem PLEASE HELP!

[whokilledsanta]

Hey

I've recently purchased a 92 model zzr250 and had it serviced by a 'gold spanner mechanic' for $350!!

It's only been a couple of months since (with a fair bit of riding) and it's just started having throttle/acceleration problems.

When the bike is sitting in neutral and the throttle is rolled back (fast or slowly), the engine revs the way it should. However, when taking off from a stand still on the bike with it in first gear, if the throttle is wound back slowly, it seems to take a few seconds to rev (like it's flooding or something), it's almost like it has a delayed reaction. It has the same problem when cruising at any speed at low revs, and rolling the throttle back slowly. If I roll the throttle back violently it seems to be fine.

Could anyone please help me with a reason why this might be happening? I don't really want to take it back to the over-priced mechanic who serviced it and the only options I have where I live is to either 'do it myself' or take it back to him.

I should mention that I've found my idle adjusting screw and have played with that a bit since I got the service because depending on the day and bikes running temperature, the idle speed varies a bit by a few 100rpm. Playing with the idle speed wouldn't cause this 'flooding' problem I have would it? I've got the idle at about 1300rpm (recommended rpm on the net) at the average running temperature at the moment and its still doing it. I have also done a day or two of mountain riding since the service and went down a few dusty dirt roads so maybe it's the air filter?? But this would have been cleaned in the $350 service wouldn't it??

Also, would anyone know where I can get an owner's and service manual for this bike other than Kawasaki? I bought one on ebay and the rip off merchant never posted it..

Advice would be greatly appreciated as I'm only new to this (first bike since I was 12) and I'm the furthest thing from a mechanic, but don't mind a fiddle. LOVE THIS SITE BTW!!

[Rossi]

manuals here

viewtopic.php?f=21&t=22293

[Nanna10r]

Depends on what km service was done & how the mech was going that day.
Buy a hard copy manual as well, it sounds like Carby hic cup. But i'd check the oil level first, toss some carbie cleaner in it & check your cush drive(how far the Wheel turns on the sproket carrier).
hth. Let us know how ya go.
Cheers Nanna

[whokilledsanta]

thanks for getting back to me so quickly. i'm not at all familiar with mechanical talk and was wondering if you would mind explaining what you mean by carbie cleaner? is that the stuff you get at supercheap that you put in the petrol tank? and what you mean by how far the wheel turns on the sproket carrier? not sure what a sproket carrier is if its not just the sproket? sorry for being so stupid, and thanks for your help again!

[Nanna10r]

No worries "santasleuth", . There's no stupid questions.
If this sin't a G-up it would be easier to get some help to you if we know some history & whereyou are. Do yourself a favour & take the time to fill in an introduction post. You may be surprised at how helpful ksrc is, if your Fair dinkum.
Answers to above are, carbie cleaner/fuel injector cleaner (supercheap ask for a unleaded bike one) then pour how ever much it says into the tank before you fill it up next time.
The cush drive is the bit between the Rear Sprocket & the rim, it's usually 6 internal rubber blocks that cushion the force betwwen the sprocket & Rim. They do wear out. Faulty one's will mean the "chain turns the rear sprocket but the Rim/Wheel is delayed in following the motion".
I'm NO mechanic & would recommend you get a Hard copy Manual & just read what seems interesting until you've read the whole thing.
Hth Nanna
Cheers Brett

[whokilledsanta]

Thanks mate. Helps alot. I'll give it a go and post on here how I go.. just figured out how to fill out my info on here so done that too. cheers

[mike-s]

I'd agree with Nannaman there, especially about the carby cleaner, actually i would suggest turning the fuel tap off, then drain the carbies as a first step as shit may have gotten into the carbs and causing problems as it just doesnt get sucked through.

Also another thing to think about is how reproduceable is the problem? is it at 1/16th a turn (barely cracking off throttle), is it 1/8-1/4 (just coming onto the needles), 1/4-1/3 or more (well and truely onto the needle taper). With the problem at each one of these different points the cause of the issue varies within the fuel systems on the carb.

Once you've drained the carbs, put carby cleaner through the bike (deliberately put it through the section of throttle opening causing the problem, a number of times) then revisit the issue. Good luck.

[edit]Oh and when your bike was given a once over, was anything done with the carbs? a general check? or pretty much untouched?. How old is the bike, how many km has it done? possible problems include (but arent limited to) crap in the float bowl, incorrect float level, blocked jets, blocked emulsion tubes, emulsion tubes worn out. Yet again, figure out the point where it starts crapping out on the throttle opening as accurately as you can[/edi]