Compression question

[wilit]

When I bought my '85 Spree from my buddy, it hadn't run in a long time. I poured some Red-Line 2-stroke oil down the spark plug hole and gave the starter a couple of turns to get the cylinder coated. I did the compression test with the whole intake tract removed (no carb, intake, or reed block) because I was waiting on a carb rebuild kit and gaskets at the time. The compression test came back at 110psi if I remember correctly. Eventually I got it running and have put maybe 60 miles on it. Since then, I've done another compression test (obviously fully assembled now) and with the throttle at WOT, I only get 62psi on the compression tester.

The bike has 4000 miles on it, and if the piston and jug isn't original, it was most certainly replaced many many many years ago. So... Was my original test at 110psi a fluke? I'm guessing 62psi is low(er) than what it should be. Is it time for a rebuild?

[martynkim]

Does it run now? If it does, your current test is flawed.

[Bear45-70]

No reeds makes your compression numbers low because the air in the crankcase is not compressed.

[wilit]

No reeds makes your compression numbers low because the air in the crankcase is not compressed.

But my no reeds test was higher than my test with reeds.


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[wilit]

Does it run now? If it does, your current test is flawed.

Yeah, it runs ok. Its no speed demon for sure.

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[ragtop89]

If you only had 60 or so PSI you wouldn't even be riding it, I think your tester maybe be busted, or wasn't sealed properly, you may want to try again.

[Dio89Elite]

The original spree wasn't a speed demon when new.
What kind of speed are you getting?

[wilit]

What kind of compression number should I be seeing?

Right now it tops out at 26mph. Take off is incredibly slow. I need to give a good push with my feet to get rolling and it takes a good distance to get up to top speed.

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[Trafficjamz]

What kind of compression number should I be seeing?

Right now it tops out at 26mph. Take off is incredibly slow. I need to give a good push with my feet to get rolling and it takes a good distance to get up to top speed.

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Sounds like a typical 85 spree to me