Hey guys so i've had an engine noise going on for a while now that i'm curious about. So the story goes, I rebuilt my 77's, 447 engine last summer, replacing piston rings, pin cir-clips (with original wrist pins), valve seals, cam guard and chain, and all gaskets and seals. Since then my bikes engine has been broken in but not much beyond that. Only got about 1 month of riding it in before it got cold last year.
My issue now is this, I adjusted the valves, the cam chain, and timing to spec at the end of last season....however after riding a bit i could hear what sounded like valve noise again. So... I opened it up and found the valves had come loose after only a day or so of riding, i chalked it up to a poor adjustment and readjusted them back into spec.
At this point I thought the noise was gone, however it was not. The noise only appeared after the bike had been properly warmed up and driven for some time which heads me in the direction of the rods. I made a note to adjust the valves when summarizing and stored it.
I started it for the first time this year last week and went for a 30 minute ride. Ride went smoothly, bike started first kick with the choke and had no other issues, however at about 20 minutes into it, the noise reappeared.
I have not yet checked the valve clearances this year, but am hoping they are loose again. If this is the case I will be replacing the tappets, under the assumption that they are probably worn out after 30 years.
However....if they are not loose.....is there a way I can check the rods without another overhaul? maybe through the sump hole?
The fact that it only makes this noise once the engine warms up is what concerns me....if the threads were going bad on the tappets I would assume heat would only cause them to snug up a bit...not get loose....yet they did just that last time.
I should also mention a rhythmic droning that also exists, upon fully warming up the engine. It can be heard through both the engine noise and the exhaust when standing farther then 5 feet away, but when i hold my hand to the end of the mufflers they are firing in synchronicity. If i come closer than five feet to the bike, its presence exists more through engine noise than the exhaust. It's like a deep waaahhhhh..............waaaaahhhhhhh.............waaaahhhhhhh........that cycles about ever two seconds. However it is not a prominently loud noise...it sounds deep within the engine if that makes sense.
What I know:
Cam chain is adjusted properly (i can hear that its not too loose) and adjuster pin moves within spec.
Ignition is timed properly. Verified with timing gun.
Starts first kick and runs fine with no popping or backfire so I assume the carbs must be in a good place but did have previous float height issues.
What I want to know:
Cause of "valve" like noise.
Source and cause of drone.
Any ideas or experience with this issue would be greatly appreciated.
I have a video that I will try to post a youtube link to once I get it uploaded.
Thank You.
My issue now is this, I adjusted the valves, the cam chain, and timing to spec at the end of last season....however after riding a bit i could hear what sounded like valve noise again. So... I opened it up and found the valves had come loose after only a day or so of riding, i chalked it up to a poor adjustment and readjusted them back into spec.
At this point I thought the noise was gone, however it was not. The noise only appeared after the bike had been properly warmed up and driven for some time which heads me in the direction of the rods. I made a note to adjust the valves when summarizing and stored it.
I started it for the first time this year last week and went for a 30 minute ride. Ride went smoothly, bike started first kick with the choke and had no other issues, however at about 20 minutes into it, the noise reappeared.
I have not yet checked the valve clearances this year, but am hoping they are loose again. If this is the case I will be replacing the tappets, under the assumption that they are probably worn out after 30 years.
However....if they are not loose.....is there a way I can check the rods without another overhaul? maybe through the sump hole?
The fact that it only makes this noise once the engine warms up is what concerns me....if the threads were going bad on the tappets I would assume heat would only cause them to snug up a bit...not get loose....yet they did just that last time.
I should also mention a rhythmic droning that also exists, upon fully warming up the engine. It can be heard through both the engine noise and the exhaust when standing farther then 5 feet away, but when i hold my hand to the end of the mufflers they are firing in synchronicity. If i come closer than five feet to the bike, its presence exists more through engine noise than the exhaust. It's like a deep waaahhhhh..............waaaaahhhhhhh.............waaaahhhhhhh........that cycles about ever two seconds. However it is not a prominently loud noise...it sounds deep within the engine if that makes sense.
What I know:
Cam chain is adjusted properly (i can hear that its not too loose) and adjuster pin moves within spec.
Ignition is timed properly. Verified with timing gun.
Starts first kick and runs fine with no popping or backfire so I assume the carbs must be in a good place but did have previous float height issues.
What I want to know:
Cause of "valve" like noise.
Source and cause of drone.
Any ideas or experience with this issue would be greatly appreciated.
I have a video that I will try to post a youtube link to once I get it uploaded.
Thank You.