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Rjm1973 · July 31st, 2015, 01:17 PM

So I did clean the head and valves. I did not disassemble the heads from the valves and lap them though.

To answer an earlier question, I'm not running a standard compression gauge in the engine as it sits right now because of course no valves are opening and closing and hence no air can really get into the chamber. I am using a leak down gauge currently that injects air from my compressor into the cylinder through the spark plug hole.

I think I understand about the rings seating, but with as low of compression as it has right now, I can't get it started. I actually replaced he rings and put it all back together and it had maybe 85-90 lbs of pressure and would not start at all. It has fuel and spark...I can tell by occasional backfire as well as verification of both. When I realized after the ring replacement that the cylinder pressure was still super low... I took the motor off the bike again and pulled the cyl off to double check the ring assembly etc. everything "looks" pretty good, but if I put the head back on, and pressurize the cylinder it goes right past the rings into the crankcase.

The cylinder looks ok, so I will prob take the Pistons off the connecting rods at this point and clean the ring grooves well and measure them. The Pistons were very carbines when I originally took it apart and I cleaned the tops only...wondering if the rings are "sticking" in the grooves somehow.

Someone asked if its ever been overheated...and unfortunately I can't say. I bought for cheap and it wasn't running when I got it. I wouldn't be surprised if it had...as I stated before, I think it's had a hard life.

July 31st, 2015, 01:17 PM	#12
Rjm1973 ninjette.org member Name: Rich Location: Kansas City Join Date: Jul 2015 Motorcycle(s): Ninja 250r, Suzuki volusia Posts: 14	So I did clean the head and valves. I did not disassemble the heads from the valves and lap them though. To answer an earlier question, I'm not running a standard compression gauge in the engine as it sits right now because of course no valves are opening and closing and hence no air can really get into the chamber. I am using a leak down gauge currently that injects air from my compressor into the cylinder through the spark plug hole. I think I understand about the rings seating, but with as low of compression as it has right now, I can't get it started. I actually replaced he rings and put it all back together and it had maybe 85-90 lbs of pressure and would not start at all. It has fuel and spark...I can tell by occasional backfire as well as verification of both. When I realized after the ring replacement that the cylinder pressure was still super low... I took the motor off the bike again and pulled the cyl off to double check the ring assembly etc. everything "looks" pretty good, but if I put the head back on, and pressurize the cylinder it goes right past the rings into the crankcase. The cylinder looks ok, so I will prob take the Pistons off the connecting rods at this point and clean the ring grooves well and measure them. The Pistons were very carbines when I originally took it apart and I cleaned the tops only...wondering if the rings are "sticking" in the grooves somehow. Someone asked if its ever been overheated...and unfortunately I can't say. I bought for cheap and it wasn't running when I got it. I wouldn't be surprised if it had...as I stated before, I think it's had a hard life.