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I got the 450 out of cold storage this weekend and tried to start it. Ok, I didn't have a battery tender on it so forget about trying to start it using the starter. But after months of storage it did start after three kicks.

I checked the oil, tire pressure, etc. and took it for a ride. The old CB is running great! Gets right up to highway speeds with lots of throttle left. Idle is also fine. I charged the battery overnight, and easily restarted it today using the starter. I know, nothing startling yet.

But, I guess I just can't leave well enough alone, and after warming it up, I checked the compression. I got < 100 lbs in one cylinder, and 120 in the other. Every thing that I've read says this bike should be real hard to start and run like crap, if you can get it running at all.

I am rebuilding another motor to replace this one (slow but sure), but do I have a bad compression tester (If so, is there a brand/model that someone could recommend)? Or, is a good running 450 possible with compression below 150?
 

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It would probably be very difficult to start the motor unless you had a steep hill to run down at only 100 psi compression. Did you read it with the motor warm and with the throttles held open? You need at least four compression pulses for the reading. You could try the compression tester on another motor - doesn't prove anything if it reads low, but if you get a high reading on another motor, your Honda compression probably is low. Compression testers aren't very expensive and seem to be pretty durable - I have a Taylor I bought used somewhere in the late sixties and it matches readings exactly with a new tester I bought last year. Leak down testers tell you more about your motor, but cost a lot more. I have a "home made" one. Useful, but a nuisance to use - the crankshaft has to be locked in place to use it.
 

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Not to contradict what anyone else says, but my 450 ran great and had a good amount of power with around 125lbs on both cylinders. I was also unsure of the guage I was using though.

GB :mrgreen:
 

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They're Hondas, they'll try to run no matter what.
But I suspect the data is wrong in both your cases, those are very low readings.

Try it again, warm engine, throttle wide open, NO CHOKE.
Then pour a bit of oil in the cylinder and take another reading.

If your figures (from your post) are correct, and you feel the bike runs great, then you absolutely owe it to yourself to ride a 450 that has 180 pounds or so going on. Get ready for a surprise...........
 
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