well this is odd ,
1998 kdx220r ,basket case unknown condition
i took the cylinder off to check the con rod and piston .
it has a wiesco piston
and the con rod /crank seem good no decernable up and down play and very little side to side.
but the cylinder bore measures with a bore gauge bang on 69 mm with a small amount of ovality going to .007mm bigger.
i am sure its meant to be 69.025 to 69.041.
no marks in the bore either.
should i send it out and get it honed into limit.
whats your thoughts .compression was only at 75 but i think the rings were stuck..
the piston was worn to 68.8.
cheers mark
odd cylinder size
- Two_stroke_brit
- Supporting Member I
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- Location: Hockley TX
odd cylinder size
Last edited by Two_stroke_brit on 12:02 pm Nov 13 2020, edited 1 time in total.
she might be older but still a fun ride.
- bufftester
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Re: odd cylinder size
Stock bore for a 220 is 69.00, stroke is 58.00
Don't hone KDX cylinders, it will damage the electrofusion coating.
If there is no visible damage to the cylinder coating (especially around the exhaust and transfer ports) then likely a new piston/rings/small end bearing and you'll be good.
Don't hone KDX cylinders, it will damage the electrofusion coating.
If there is no visible damage to the cylinder coating (especially around the exhaust and transfer ports) then likely a new piston/rings/small end bearing and you'll be good.
- Two_stroke_brit
- Supporting Member I
- Posts: 35
- Joined: 07:18 pm Sep 09 2020
- Country: United States
- Location: Hockley TX
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Re: odd cylinder size
Agreed the plating is too thin to work with like that with the head mod i have 175 psi i believe stock is around 145 cylinders that are oblong are worn and should be replated in your case it will be a little cheaper since there arent any deep scratches that will need to be welded i think mine was 290 with welding millenium does great work and it will be better than new
Good luck get that thing running this is a great time of year to ride!
Good luck get that thing running this is a great time of year to ride!