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Discussion Starter · #1 ·
I have a '72 CB450 that I have done everything imaginable to try to fix my engine problem but can't figure it out ( Compression test, Cam chain adjustment, valve adjustment, static timing, cleaning of mechanical advance unit, new plugs, Carb rebuild and sync)!!! The problem is that the bike is kinda lacking in low end grunt and it won't cruise at any rpm about 5,000. It is 100% stock with 3,900 miles.


Anyways, if any of you know a good Honda mechanic in Northern Virginia or surrounding areas or know someone on the board familiar with 450's, please please please let me know.

I have also posted this message over on SOHC/4.

Thanks,

Daniel (703) 727-1272
 

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Sensei
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What were your compression readings?
I'm in Roanoke.....But go to Winchester regularly.... Steve
 

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Discussion Starter · #4 ·
ol55 said:
Where in NOVA are you? I'm near Leesburg.

Larry
I'm in Round Hill just past Purcellville on 7. It would be great if we could get together sometime soon. I could bring the bike out to you or you could drop by my place....either or. My cell is (703) 727-1272. If you get a chance, gimme a call.
 

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Discussion Starter · #5 ·
66Sprint said:
What were your compression readings?
I'm in Roanoke.....But go to Winchester regularly.... Steve

I cant remember my exact numbers but when I did it at the time, from what I read they were good. I'll do another test when I get home from work today.
 

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Sensei
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163 PSI is the absolute minimum for a 450 (should be 175/180).......Unsynchronised carbs will ofter show similar symptoms....
 

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Discussion Starter · #7 ·
66Sprint said:
163 PSI is the absolute minimum for a 450 (should be 175/180).......Unsynchronised carbs will ofter show similar symptoms....
Just did a compression test this morning. If my numbers are correct, both cylinders read 110 psi. I guess when I first did the test awhile back, I didn't know the numbers should be around 175/180. Hard to believe on a bike with only about 4,000 miles. I guess now it's either new rings and a honing or sell it.
 

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Sensei
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I'd try a good soak in PB blaster or Kroil first (maybe a week) and then kickstart with the plugs out to remove the penetrant (messy but effective)..... Then run it a good bit and recheck compression PSI hot...... If below 160, the rings are either well worn, or too glazed, or not "broken free"..... (sometimes they just get "stuck" by dried oil or fuel/carbon from "sitting")...... I have had this work on 130PSI engines, but you MAY be in for a re-ring....
 

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Steve -

Maybe he should change the oil after putting that stuff in the cylinders.
And again shortly after he gets it running.......
 

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Yes, DEFINATELY!...
Another case of my forgetting to write EVERY step I do (including the "automatic" ones).....
Good Catch!.... :D
 
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