Cam chain noise.
All of the valves were at .004, even were a little tight getting the feeler gauge under them. I took the cam chain tensioner out to ensure the spring was working correctly, it seemed fine. The chain is so new and tight that there is barely any movement when moving the crank, like less than 1mm. But it's locked and set.
That loud knocking sound is still there. I've never heard a Dream run before so I don't know how it's supposed to sound, but I don't know what else it could be given that everything is new and tight and to the best of my knowledge in there correctly. I know the exhaust is pretty loud and is letting lots of noise out but it's hard to determine where the sound is coming from. It could even be something loose outside of the engine vibrating and hitting the frame I suppose? 1964 CA72
1974 BMW R75/6 1969 CL450 1995 Toyota Corolla Wagon (The Hauler) I would love to try and help you, you say "That loud knocking sound is still there" it sounded like a ticking sound rather than a knocking to me.
You say the engine vibrating and touching the frame that should be easy to detect. Did you try the screwdriver trick to determine if the sound is coming from the top or bottom of the engine. If the C72/77 engine is like the CB77 I own then the engine should only be a slight russell when new and after many miles a little more noise as part loosen up I have had two new CB's and they were so quiet when running no knocking or ticking. If you have no baffels in the exhaust mufflers then put some in, fast and quiet is the game not slow and loud. Did you do the engine strip down ?.
I will try the screwdriver trick tonight, my only concern is that I'm mostly deaf (hence my username) so things are a little harder for me to detect :) Yes, I did an engine strip down. I bought the bike with low compression. There was too much play in the pistons so I had the cylinders bored and put in .50 over pistons, rings, new pins and clips for them. Then new valve guides and cam chain and rollers while the head was apart. Then new transmission shafts and gears. As far as I could tell everything was done to the book, I checked all clearances, etc. That doesn't mean I didn't make a mistake but I thought it was strange to hear such a prominent noise when everything is new and tight, ya know? I may ride it to the local mechanic if I can't determine the origin, he'll have more sensory ability than I do to listen for engine issues. I've never put baffles into a muffler before, I'll have to find somewhere on this site to see how others have done it. 1964 CA72
1974 BMW R75/6 1969 CL450 1995 Toyota Corolla Wagon (The Hauler) I too are deaf and it's not easy to hear these things but if like me you can hear the noise then it must be a lot louder to someone with good hearing.
Please I do not wish to be rude but would you say you are a competent person when it comes to working on a engine is this your first 4 stroke Jap bike engine you worked on ? Jap engines are not as forgiving as say a old Brit engine. Did you gap the piston rings when you installed them, also you say the new cam chain is very tight when installed, you know I have a feeling there maybe were your problem comes from but like I say im no expert. Good luck with your local mechanic do let us know any out come.
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