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NIKASIL / REPLATE CYLINDERS

Replate or Nikasil one cylinder hole $356 cdn.

Replate one cylinder hole with welding $436 cdn. 

When replating a cylinder there are many varibles and issues that happen when replating is done.

Most dealership shops and bike or snowmobile owners don't realize the issues and think the replating must be good, and feel there going to save a few bucks by dealing direct with a replate company and not with a engine shop.

So here are a few issues we have come across over the years that if the cylinder is not measured and inspected properly catastrophic damge can occur.

-Measure the cylinder bore to make sure it has proper piston clearance and is round, alot of the bore holes are not perfectly round, tighter in some sections then others which can cause a seize. Sometimes the bore is too tight or to loose on the piston clearance and we have to send it back to be redone to make sure it is perfect.

-Chamfering the port edges. After the cylinder is finally honed the port window edges are real sharp squared edges. These edges can scar a piston and cause a seize. So after we get cylinders back from replating we use a special tool to cut all the edges back and sand them for a nice round edge not to catch the piston. Keeping the engine more reliable.

-When nikasil is applied to the bore of the cylinder it also goes inside the port windows. This makes the ports smaller, causing less airflow and making less HP! So we re-port the cylinder with special tools carving out the nikasil in these windows getting the ports back to there original size and getting back 3-5% hp lost from nikasil closing up the window.

-After the replating process the top of the cylinder is decked to flatten out the top surface of the cylinder for a good seal of the head gaskets. When this happens the cylinder is shortened maybe by a couple thousands of an inch and maybe more. This will affect the piston to head clearance as we call the squish clearance and squish velocity. This will also effect the compressin ratio, how the engine runs, might not make the rpms it once did, and lead to detonation causing engine damage. This needs to be measured and applied to the rest of the engines dimensions and specs. especially when dealing with a twin cylinder engine and one cylinder is replated and decked, causing one cylinder to be lower then the other. Once a mono head is placed on top it might not seal properly.