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OLD ktm250sx piston height

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Hey guys had an old 1992 ktm250 come in the garage. Story was it didn't run. The owner bought a new piston kit, put it in and it fired up but has absolutely no power. I ran a compression test and got 60 psi so I tore into it. What I found was a new piston. A bore that was junk to my standard but ive seen bikes run with worse but what caught my eye was the piston height? The top of the piston is .165 below the gasket surface?? Is it possible he got ahold of a piston with the right bore but the wrong wrist pin location? 

20170916_151046.jpg

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Bump.....anyone know the squish on these old motors. I'm positive this it far too big but just trying to figure out why

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Wossner is a great source for this info:

Wossner website, 92 KTM250 piston info

Part Number    8005DA
Bore Size    67.5 mm
Clearance    0.06 mm
Compression Height    29.7 mm

Some KTM 125/200 cylinder heads drop down into the cylinder. From pictures of heads on Ebay, this doesn't seem to be the case with the 1992-250. 

 

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21 hours ago, sbest said:

Wossner is a great source for this info:

Wossner website, 92 KTM250 piston info

Part Number    8005DA
Bore Size    67.5 mm
Clearance    0.06 mm
Compression Height    29.7 mm

Some KTM 125/200 cylinder heads drop down into the cylinder. From pictures of heads on Ebay, this doesn't seem to be the case with the 1992-250. 

 

Thanks so much sbest. On this wiseco I'm getting 26.65 compression height. That's center of wrist pin to top of piston. So according to my math that's .120 shorter than it should be. The question is tho.....why? The bore is right. Someone measured the bore and picked up the first 67.5mm piston they came across.....hmm

 

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