Maintenance & Technical > KX500 Original

KX head sealing question

<< < (2/2)

mdw471:
KXcam

was it a rz or an lc....i can also vouch for the fact that it works on an LC

i wonder if the one piece, two barrell head might offer a greater mating surface than the KX?

Mark

hillclimber147:
Thanks guys for the opinions. I'm building a "KX 560" with a CR500 rod and 91mm piston. I had to move the cylinder up 5.5mm for the piston skirt to close the exhaust port at TDC. The head, combustion area, was milled out to copy a CR500's head, but the volume was only taken out to 52cc not 60cc like the CR500, because the water passages were getting close. So I held off on milling the cylinder in order to verify what the compression would be. And like I said above it only came to 110 lbs. Unfortunately I have finals this week and a hillclimb coming up so I'm scrambling trying to get this done in time! Afterwards I'll tear it down and have the cylinder milled down.

KXcam22:
MDW,
 That is a good point. It was the RD350LC.  A bit different from the KX in that the 4 cylinder studs go thru the cylinder and head vs the KX which has cylinder mounted studs, although more and radially spaced. Might make a different in the type of clamping effect the head gets. Still though I think it should seal - there is likely more issues with too little squish clearance than with sealing. Cam.

demographic:

--- Quote from: hillclimber147 on May 07, 2007, 12:47:35 AM ---Thanks guys for the opinions. I'm building a "KX 560" with a CR500 rod and 91mm piston. I had to move the cylinder up 5.5mm for the piston skirt to close the exhaust port at TDC. The head, combustion area, was milled out to copy a CR500's head, but the volume was only taken out to 52cc not 60cc like the CR500, because the water passages were getting close. So I held off on milling the cylinder in order to verify what the compression would be. And like I said above it only came to 110 lbs. Unfortunately I have finals this week and a hillclimb coming up so I'm scrambling trying to get this done in time! Afterwards I'll tear it down and have the cylinder milled down.

--- End quote ---

91mm piston?

Would that be a 2mm oversize CR piston then as I have never seen a KX piston bigger than 88mm?

Navigation

[0] Message Index

[*] Previous page

Go to full version