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Old 09-15-2012, 01:28 AM   #1
hondarider511
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low compression after rebiuld??

i know this is a long shot, i have a 1974 honda qa50 i rebuilt the motor(ran fine b4 rebiuld)piston to cylinder clearance was good so i just put new rings and honed the cyl.....torqued all bolts to spec and in correct pattern....its showing 60 psi on my tester but i havent put it in the bike to see if it will start......is it just bc the rings havent seated yet??it was only going to 30 psi until i put a drop of oil in the cylinder wich jumped it to 60 so im assuming that means the rings arent sealing well..........
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Old 09-15-2012, 02:38 AM   #2
bluewave18
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Have you done a leak down to check the valves?
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Old 09-15-2012, 02:57 AM   #3
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Quote:
Originally Posted by bluewave18 View Post
Have you done a leak down to check the valves?
This and did u off set the rings correctly?
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Old 09-15-2012, 03:25 AM   #4
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He probably forgot to put the piston in. It gets me every time.
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Old 09-15-2012, 06:26 AM   #5
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Do you have the throttle wide open when you test? Gotta pull in some air to compress
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Old 09-15-2012, 07:22 AM   #6
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if you honed like you should have with new rings, prolly havent seated yet.
of course you did rebuild it for a reason, to me that says you need a leakdown test, valve seats could be leaking, cylinder could be oval etc etc
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Old 09-15-2012, 01:50 PM   #7
hondarider511
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valves dont leak, and are set correctly.timing is good.... rings are put on the way the old ones came off but theres no info about the order they go.....im restoring the bike and fig since i had the motor tore down i would just do the rings...i wish i would done a check b4 i tore her down....and yes i have the carb wo while doing the check
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Old 09-15-2012, 08:52 PM   #8
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Are you sure the cam is timed correctly?

Brad
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Old 09-15-2012, 09:22 PM   #9
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Quote:
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Are you sure the cam is timed correctly?

Brad
positive......... i got bored today, threw the motor in the frame, put the carb on and first kick she started up and purred like a kittin........im going to check the compression again after a few hours of use
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