Engine Knocking

Joined
May 14, 2001
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#1
I am lost...I got this knocking sound in my engine at idle..and can not locate it. The set up..Recently I bolted on a FMF Gnarly pipe and Turbine Core 2 silencer on my 99 KDX 200 (stock Jetting). While out on a seventy mile ride I noticed around mile 60 this knocking .pinging. I thought my pipe may have been loose or the pipe guard. Got it home tightened up all the bolts still hear it. I bought the bike used and just started to ride it hard after a year..so I did a top end job..and added boyesen power reeds.Still got the sound. Changed the Gas (Ultra 94 and H1R at 40:1) and plug. Cleaned air filter .carb. still got it..Is it possible this sound is coming from the water pump..The vibration seems the strongest there when I put my hand on it. The manual says check the CDI and ignition timing..I'll be doing that today...Any ideas. I already sat out one race due to this noise, don't want to miss another. Any replies appreciated.
 

MADisher

Grand Data Poohbah
Joined
Apr 30, 2000
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#3
If it sounds like a diesel idling off in the distance...

That's a factory KDX sound. :( Is it worse when you rev it ? Cause the stock factory rattle doesn't increase with rpm. At least mine doesn't.

Though that's a tranny rattle not in the top end.

-MD
 
Joined
Dec 10, 2000
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#4
Kawasaki has notoriously noisey engines. The power-valve governor and the water pump contribute to a lot of the rattly sound that eminates from them.
 
Joined
Jul 23, 2001
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#5
My 1994 kdx200 spark knocks when i pull a tall gear, I contribute most of this to my obesity (about 250lbs.). Is this caused by some sort of mechanical problem, or am I realistically to heavy for the bike? By the way, i use 93 octane pump gas.
 
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#6
When was the last top-end done? Carbon deposits on the piston crown and in the combustion chamber can cause detonation under a heavy load. Too hot of a heat range on the plug can also be a culprit in this. A KDX shouldn't ping with 93 octane ( as long as the gas is fresh ), as they are relatively mildly tuned engines, and they don't have extremely high compression ratios. You may also want to check the timing, too much advance can cause detonation. It has been my experience that most KDXs have slightly too much advance from the factory, and they typically benefit from retarding the timing very slightly. If the jetting is still stock, that is definitely not the cause of the pinging, as KDXs come jetted way too rich. If it has been re-jetted, a too-lean jetting condition can contribute to pinging, but I don't think I have ever seen a KDX that was too lean.:p
 
Joined
Jul 23, 2001
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#7
I don't have any idea when the last top end job was performed, i bought the bike appox. two months ago. One of the few tools that i do not own is a compression tester, at least that would give me a general idea of how worn it is. I am running a b8es plug, and am not sure of the jetting (i have yet to remove the carb.) I just ordered a sevice manual today, when it arrives i will check and reset the timing. This is the first modern bike i have owned so i dont have any jetting experiance. This knock only occurs right before the powervalves open completly, and it only does it shifting into fith or sixth gear. Smaller people who have ridden it think i am full of poo (they cant make it do it). That is why i thought that my weght was causing the ping.
 

70 marlin

Mi. Trail Riders
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Aug 15, 2000
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#9
might want to inspect your kipps valve?

spudric's bike had no bottom end and sounded like a diesel© popped of left side side cover ¥ looks like big screw¤ and with a 10mmsocket and wrench tried to exercise it gently, no movement ! of came head & jug, and shipped for service and inspection of plating& bore by mr gorr!!!!!!!!!!!
 
Joined
May 14, 2001
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#10
Re:Knocking.

I think I have narrowed it down. When you engage the clutch the sound went away. I opened up the cluth, and the bearing is a little granny, I am also told to replace the bearing behind the clutch basket. I will replace these bearings and let everyone know how it went...Thanks for the replies.:cool: