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Discussion Starter · #1 ·
I have a 2009 sportsman 850xp that was boring alot of oil towards the end. It inevitably sheerd the cam sprocket pin and bent valves. I was going to hone and replace the rings , then everything on the way back out but in the service manual it says not to hone cylander when replacing rings.... so now what?馃槼


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2008 800 ho efi, 2019 850 SP premium
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The cylinders are plated with a composite material and you can hone them if you want to, but the composite material (silicon/boron/carbide and other metals) is so hard that a typical glaze breaker or rigid hone hone will not impact the coating. From the pictures it appears the composite coating is worn through at the top of the cylinders. I suggest if rebuilding, to sent the cylinders along with the new pistons to a cylinder plating service to have the cylinders renewed and sized correctly to the new pistons.

It is recommended when servicing a plated cylinder engine that the cylinders not be honed when installing new pistons and rings as it is simply a waste of time, however, just to clean the cylinder prior to installation of new pistons and rings, using a green scratchy pad (Scotch Brite) to remove dirt and carbon.
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