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FreeRide · 02-04-2015, 10:41 PM

SOOOO CLOSE.. But stuck now.Help?

I bought a new psiton, as the old one had been crunched by that chunk of valve seat enough that the rings were stuck. Crankshaft measures within spec though, luckily.

So, im at the step of installing the piston on the crankshaft in the cylinder...

I can get the new piston and rings into the cylinder on the bench jsut fine with a can-type ring compressor. Slides in easy, moves around nice, great.

But, then i want to push the piston out the bottom of the cylinder enough to get the wrist pin installed to the crankarm, but this is far enough down to have the lowest ring pop off. The manual gives no advice how to do the assembly of the piston into the cylinder. Id install the piston onto the crank, then drop the cylinder down onto the piston using a ring compressor, but the taper at the bottom of the cylinder liner makes the band type compressors useless. Is this taper meant to guide the rings in as you tap the cylinder down from the top? Seems like a great way to trash some rings.

What is the order of operations on installing a piston onto the crank, and getting it into the cylinder? Cant find any info anywhere. If only the damned ring was a sixteenth higher up the piston, you could insert the piston into the cylinder, then simple slide the wrist pin in, jsut like in this video.

02-04-2015, 10:41 PM	#6
FreeRide Junior Member Join Date: Jan 2015 Posts: 8	SOOOO CLOSE.. But stuck now.Help? I bought a new psiton, as the old one had been crunched by that chunk of valve seat enough that the rings were stuck. Crankshaft measures within spec though, luckily. So, im at the step of installing the piston on the crankshaft in the cylinder... I can get the new piston and rings into the cylinder on the bench jsut fine with a can-type ring compressor. Slides in easy, moves around nice, great. But, then i want to push the piston out the bottom of the cylinder enough to get the wrist pin installed to the crankarm, but this is far enough down to have the lowest ring pop off. The manual gives no advice how to do the assembly of the piston into the cylinder. Id install the piston onto the crank, then drop the cylinder down onto the piston using a ring compressor, but the taper at the bottom of the cylinder liner makes the band type compressors useless. Is this taper meant to guide the rings in as you tap the cylinder down from the top? Seems like a great way to trash some rings. What is the order of operations on installing a piston onto the crank, and getting it into the cylinder? Cant find any info anywhere. If only the damned ring was a sixteenth higher up the piston, you could insert the piston into the cylinder, then simple slide the wrist pin in, jsut like in this video.
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