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Discussion Starter #1
Where on earth should I look for a 0.0012" feeler gauge for checking the valves on my honda CB450? The smallest I've found locally is 0.0015" and the valves are clacking a bit when set to that(I'll make sure they haven't loosened up or something tomorrow, it hasn't been run for 20-30 years until today).
 

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Re: 0.03mm/0.0012" feeler gauge.

I wouldn't worry, the size you have is fine.
 

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Re: 0.03mm/0.0012" feeler gauge.

Most of the group sets to .002", I set to .0015"...either works fine....
 

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Discussion Starter #4
Re: 0.03mm/0.0012" feeler gauge.

Cool, then I'll check them again. I adjusted them with my dad before running it and once it started up, they were clacking. Maybe they've come loose or something, after all... It's the first time it's been run in 20-30 years.
 

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Re: 0.03mm/0.0012" feeler gauge.

Sevalecan said:
Cool, then I'll check them again. I adjusted them with my dad before running it and once it started up, they were clacking. Maybe they've come loose or something, after all... It's the first time it's been run in 20-30 years.
I have to ask....Where did you adjust the clearance? Between the valve top and follower (rocker) or between the follower and cam?
 

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Discussion Starter #6
Re: 0.03mm/0.0012" feeler gauge.

Between the valve top and the follower. I'm somewhat convinced that it's not valve clearance that's making the noise now, however. I had it running and tried tuning it by ear, and you could get it to the point where it was too tight and it still kept knocking, none of the adjustments for the valves affected it.

I'm fairly confident that the noise is in the top of the engine though, I checked with a screwdriver to my ear and a stethoscope for this sort of thing, and the sound seems much more prominent at the top and almost non-existent at the crankcase. It's not a very deep sounding noise either. It's driving me nuts though.
 

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Well,.... On a 450 you check the clearance between the cam lobe and the 'follower pad" on the tappet, NOT between the tappet and the valve itself.......
 

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66Sprint said:
Well,.... On a 450 you check the clearance between the cam lobe and the 'follower pad" on the tappet, NOT between the tappet and the valve itself.......
Damn you're quick Steve :D As Steve said, DON"T try to adjust the valves with the engine running otherwise you will be hearing loud nocking noises coming from the exploding engine!!
 

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Discussion Starter #9
otr002 said:
66Sprint said:
Well,.... On a 450 you check the clearance between the cam lobe and the 'follower pad" on the tappet, NOT between the tappet and the valve itself.......
Damn you're quick Steve :D As Steve said, DON"T try to adjust the valves with the engine running otherwise you will be hearing loud nocking noises coming from the exploding engine!!
Hah, well, if it would explode for me that would certainly be easier to diagnose(No, I'm not trying to make it explode.)! I'd certainly hope the valve seats didn't melt in that short period of time, but if so I figure that can be fixed with a valve job, and it looks like I'm going to take the head off anyway to find this problem. Hopefully that won't take me too terribly long to do. It's a little discouraging once you've finally got something running and you realise it makes a clacking noise and you can't seem to fix it without tearing it down.

If I could get this darn camera to work in linux I'd make a thread showing off my project.
 

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Did you adjust the cam chain? I would do that before you take the head off and see if that quiets it down.
Don
 

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Discussion Starter #11
Yes, we had adjusted the cam chain before putting it together, though I searched this forum for knocking and saw mention of it and was planning on checking it again before I completely disassembled it anyway. Sure enough, there was some slop in the chain, so I loosened the bolt on the cam chain tensioner and decided to give a little tug and see if it was springy at all, I added more slop to the chain and it hasn't picked up. Is there a way to manually adjust the cam chain?

It seems my biggest problem with this thing isn't mechanical issues, it's the emotional roller coaster of "is my engine on the verge of blowing up now that I put all this effort into getting it running?"
 

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Discussion Starter #12
So, I took off the tensioner and inspected it, it really seems to be working as good as it appears like it should be, so I tensioned the cam chain back up to where it was, really it wasn't too bad.

So I decided not to put my faith in that little repair. I also rechecked the valves, this time between the follower and the cam, so those should be fine. Now I've taken off the left crank case cover to access the starter chain... Which is incredibly loose and flopping all over, hitting the case. I would swear the noise wasn't coming down from that low. But I'm pretty sure it was primarily on the same side as the starter chain.

We'll see what happens if I leave the chain out or something, but I need a new crank gasket first. I suppose it could be causing my knocking noise, but it theoretically shouldn't be spinning when the engine is running, right?
 

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Discussion Starter #13
Fixed the clacking, maybe the cam chain really was loose. I decided the tensioner wasn't all that strong and put some welding rod in the back to help it tighten up, noise is gone.. and now I have oil all over the floor from running it without the front valve cover on :roll: . Sweet. This machine will live again!
 

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66Sprint said:
Well,.... On a 450 you check the clearance between the cam lobe and the 'follower pad" on the tappet, NOT between the tappet and the valve itself.......
Is this the same on a 78 hawk?
I tried to adjust my valves... and now it wont stop back firing, and kind of seems like the power cuts in and out when riding,,,, (just on the test ride, not riding untill I figure this out)
 

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never mind... the spark plug some how got squised and the electrode was tutching the base... im an idiot..
 

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Gunny said:
never mind... the spark plug some how got squised and the electrode was tutching the base... im an idiot..
You sure you've got matching and correct plugs in that bike??



GB :mrgreen:
 

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yea. they are the recomended ngk plugs, I must have just dropped it at some point... oops
 
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