ninjette.org - View Single Post - Taking a Stab at Compression issues. 2007 250 ninja.

greg737 · November 12th, 2015, 08:23 AM

Are you working with a copy of the Kawasaki Ninja 250 Motorcycle Service Manual? It's full of interesting tidbits...

Example: the very first item under the heading "Compression Measurement" (on page 4-11) says "Thoroughly warm up the engine so that engine oil between the piston and cylinder wall will help seal compression as it does during normal running."

The Service Manual cylinder compression range is 139 to 213 psi.

I know that by the time people get around to trying to diagnose their engine's health with a compression test they often have the bike pretty well disassembled to the point that it won't/can't run, but it's important to know how the manufacturer meant the test to be carried out.

And it's not just Kawasaki prescribing a warmed up engine for compression testing, every service manual I've ever read said to warm it up.

November 12th, 2015, 08:23 AM	#3
greg737 - Name: - Location: - Join Date: May 2009 Motorcycle(s): - Posts: A lot.	Are you working with a copy of the Kawasaki Ninja 250 Motorcycle Service Manual? It's full of interesting tidbits... Example: the very first item under the heading "Compression Measurement" (on page 4-11) says "Thoroughly warm up the engine so that engine oil between the piston and cylinder wall will help seal compression as it does during normal running." The Service Manual cylinder compression range is 139 to 213 psi. I know that by the time people get around to trying to diagnose their engine's health with a compression test they often have the bike pretty well disassembled to the point that it won't/can't run, but it's important to know how the manufacturer meant the test to be carried out. And it's not just Kawasaki prescribing a warmed up engine for compression testing, every service manual I've ever read said to warm it up.