220 knock sound off idle

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ridinredneck
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220 knock sound off idle

Post by ridinredneck »

recently picked up a 98 kdx 220 that i bringing back to life. it runs but the silencer on it was nothing but hollow. everything in it was gone. it was loud lol. i now have a stock silencer on it (much quieter) and i can hear a knock sound just off idle. it is not a continuous knock. if i quickly blip the throttle i can hear a single knock sound. or if if lug it i can hear it a couple of times. it needs a rejet done (on the rich side now) and it has a slight exhaust leak where the pipe goes in the cylinder. its not the kips. completely different sound. i take good care of my rides and have never experienced piston slap. will that sound like this or be a continuous sound? i have not looked at the top end and dont know how many hours are on it. i plan on a rebuild soon but just wondering about this sound.
ohgood
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Re: 220 knock sound off idle

Post by ohgood »

I hope it's not a poison about to explode, like mine was.
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6 Riders
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Re: 220 knock sound off idle

Post by 6 Riders »

ohgood wrote:I hope it's not a poison about to explode, like mine was.
He means piston! It sounds like your piston is about to (or has) let go. Don't run that bike until you get the jug off and inspect everything!
newbbewb wrote:^what he said.
masterblaster wrote:Man 6 riders you rock.
*side note...I'm drunk, so try to read what I'm trying to say, instead of what I actually type
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Julien D
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Re: 220 knock sound off idle

Post by Julien D »

Being a 220, and a few years old, the first thing you need to do is pop the cylinder off and verify that you are not running the weak stock piston.
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ridinredneck
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Re: 220 knock sound off idle

Post by ridinredneck »

thanks for the replies. i will be tearing the top end off in a couple of days. i will post what i find.
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JoKDX220r
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220 knock sound off idle

Post by JoKDX220r »

http://www.kdxrider.net/forums/viewtopi ... =77&t=9362
I already had this kind of noise in my engine if you click on the link I posted 2 videos about it..
good luck with that !!
ridinredneck
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220 knock sound off idle

Post by ridinredneck »

when i tear the top end off i will be sure to check the play in the rod and the side crank bearings. thanks
ridinredneck
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220 knock sound off idle

Post by ridinredneck »

well i FINALLY got time to tear off the top end. OMG!!!!!! the piston is busted and the cylinder is trashed. i honestly dont see how it ran. i cant seem to find a good used cylinder anywhere so i need some help on who to send it to. i want to get it replated and possibly bored out.
BTW Thank God the crank and rod is in good shape
ohgood
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Re: 220 knock sound off idle

Post by ohgood »

ridinredneck wrote:well i FINALLY got time to tear off the top end. OMG!!!!!! the piston is busted and the cylinder is trashed. i honestly dont see how it ran. i cant seem to find a good used cylinder anywhere so i need some help on who to send it to. i want to get it replated and possibly bored out.
BTW Thank God the crank and rod is in good shape
j

man that's too bad. i ran mine for a while until I realized it was time. way past timeImage
ridinredneck
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Re: 220 knock sound off idle

Post by ridinredneck »

ohgood wrote:
ridinredneck wrote:well i FINALLY got time to tear off the top end. OMG!!!!!! the piston is busted and the cylinder is trashed. i honestly dont see how it ran. i cant seem to find a good used cylinder anywhere so i need some help on who to send it to. i want to get it replated and possibly bored out.
BTW Thank God the crank and rod is in good shape
j

man that's too bad. i ran mine for a while until I realized it was time. way past timeImage
man that piston looks brand new compared to mine lol. it was like this when i got it. i hate it when people wont do simple maintenance. its gonna cost me a fortune to get it fixed
KarlP
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Re: 220 knock sound off idle

Post by KarlP »

Very cool. No blow by, eh?

Cylinders are easily repaired by the platers. Give a call to a couple of them
'08 KTM200xc
'99 CR/KDX Hybrid with that RB stuff done to it
KX100 for the boy
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