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Discussion Starter #1
Hello all, I own a 1974 CB360 that only has about 1600 miles on the motor. I rode it the other day for about 20 minutes at which point the bike cut off on me and I had to have it towed home. I get it home and charge the battery, thinking that it’s probably just because I let the battery sit for a few months. Any way, I hit the electric start and I hear a LOUD knocking sound, seemingly coming from inside the case. Thinking the starter clutch could be bad, I rebuilt the starter clutch and the starter motor. Just got it reassembled and it’s STILL making the loud knocking noise inside the case. Around a year ago I replaced the cam chain tensioner and cam chain guide, could this be a slipped cam chain tensioner causing this?

I want to upload a video of me showing the knocking sound, but I don't know how to upload one.

All input is greatly appreciated.

Thanks, Gary.
 

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Discussion Starter #4
It still sounds like the starter clutch to me. You replaced the caps, springs and rollers? Did you check the outer housing those parts go in to see if it was cracked?
Yeah I replaced the caps, springs, and rollers. And the starter clutch housing isn’t cracked. The rotor is also brand new from ricks electronics.
 

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Yeah I replaced the caps, springs, and rollers. And the starter clutch housing isn’t cracked. The rotor is also brand new from ricks electronics.
What about the drive sprocket? If the surface where the rollers grip is worn or the surface is choppy from roller slippage in the past, it might have to be changed as well
 

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Discussion Starter #8
So does it make the noise when kick started? Running? If no, then it's still somewhere in the starter clutch or motor
I kick started it, it cranked then made the knocking noise a couple times and died. Then when I tried to kick it again, the kick starter kicked back and almost hurt my leg.
 

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Well that changes things, obviously. It's starting to sound like something in the engine, but without being there to hear it in person it would be difficult to tell what it might be. I've not worked on a 360 cam chain tensioner. Is that the reason you did the top end previously? What else did you do while it was apart? How long has it been since you checked the ignition timing? Kicking back that hard is unusual
 

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Discussion Starter #11
Well that changes things, obviously. It's starting to sound like something in the engine, but without being there to hear it in person it would be difficult to tell what it might be. I've not worked on a 360 cam chain tensioner. Is that the reason you did the top end previously? What else did you do while it was apart? How long has it been since you checked the ignition timing? Kicking back that hard is unusual
The best way to describe the sound is like metal slamming into metal, slapping if you will. And yes that is why I got into the top end, I replaced the cam chain tensioner and the cam chain guide. About a year ago I installed a Charlie’s Place electronic ignition as well as high output Dyna coils. I got the timing dead on, and haven’t touched it since. Just prior to the last ride the bike would crank immediately and idle amazing. Around the same time that i got the new ignition, I bench and vacuum synced the carbs and got them tuned in very good.
 

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Did you STAKE the screws that hold the starter clutch to the new rotor?.....One of those backing out can be very noisy, and your vid is not long enough to clearly determine the sound source......Also, WHY are you opening the throttle when starting?.....Properly tuned and adjusted, just touching the start button should be sufficient.....
 

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Discussion Starter #13
Did you STAKE the screws that hold the starter clutch to the new rotor?.....One of those backing out can be very noisy, and your vid is not long enough to clearly determine the sound source......Also, WHY are you opening the throttle when starting?.....Properly tuned and adjusted, just touching the start button should be sufficient.....
All of the screws on the starter clutch are tight and completely flush, and the reason i was opening the throttle was due to the fact that I haven’t been able to get it to crank since I last rode it. The bike will just spin over and about two times a second will make that awful noise. Prior to riding the last time it WOULD start just by a touch of the button, or one kick.
 

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DID YOU STAKE THE SCREWS...YES or NO?
"Tight and flush" does NOT answer the question.....
Hearing the engine instead of intake noise could help.....
It was "cranking"....Do you mean start by "crank"?
 

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Discussion Starter #15
DID YOU STAKE THE SCREWS...YES or NO?
"Tight and flush" does NOT answer the question.....
Hearing the engine instead of intake noise could help.....
It was "cranking"....Do you mean start by "crank"?
I did not stake the screws, a shop installed the housing onto the new rotor about a year and a half ago. I’d like to show you a video of the engine running but I cannot get it to start. Also, by cranking I do mean starting and running.
 

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Perhaps try turning the engine slowly by hand to try to determine where in the rotation of the engine you are having interference. Easy enough to remove the stator cover, definitely worth a look.
DID YOU STAKE THE SCREWS...YES or NO?
Sprint, Just wondering is loctite is not sufficient to keep the screws from backing out?
 

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The design, which included small slots on either side of the screw head to "stake" the heads of the screws into for locking purposes, was prior to anything like Loctite being available - and I suppose Loctite would work but knowing the potential for these screws to come loose due to the forces they encounter while turning the engine to start it, including the occasional kick back the opposite direction, I'd do both in these times. Added to the above. these engine vibrate enough to loosen many fasteners not fully tight as it is. Accurate answers help narrow down the situation better. Since the OP did not do the installation, I'm not sure how he knows the hosing isn't cracked... for those not overly familiar, it's easy to miss a crack in the outer shell of these starter clutches - and it will absolutely slip and make nasty grinding noises if so. OTOH, a long, better video of the sound would also help
 

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Discussion Starter #18
The design, which included small slots on either side of the screw head to "stake" the heads of the screws into for locking purposes, was prior to anything like Loctite being available - and I suppose Loctite would work but knowing the potential for these screws to come loose due to the forces they encounter while turning the engine to start it, including the occasional kick back the opposite direction, I'd do both in these times. Added to the above. these engine vibrate enough to loosen many fasteners not fully tight as it is. Accurate answers help narrow down the situation better. Since the OP did not do the installation, I'm not sure how he knows the hosing isn't cracked... for those not overly familiar, it's easy to miss a crack in the outer shell of these starter clutches - and it will absolutely slip and make nasty grinding noises if so. OTOH, a long, better video of the sound would also help
When I took the rotor off I visually examined the housing that I could see while it was attached to the rotor. I’ll take the side cover off once more and remove the rotor as well as the starter clutch housing. I’ll make a longer video prior to removal, I will also post pictures of the housing once I remove it from the rotor.
 

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And there might be the key - the cracks that can happen in the housing of the starter clutch often can't be seen with it mounted on the rotor. There is a sheet metal cover over the cast housing, but the cast part underneath is what cracks and allows it to expand in diameter which allows the rollers to slip badly. Again, this might not be the cause of the noise, but unless every single part is carefully and thoroughly inspected, you can't rule it out
 

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Discussion Starter #20
And there might be the key - the cracks that can happen in the housing of the starter clutch often can't be seen with it mounted on the rotor. There is a sheet metal cover over the cast housing, but the cast part underneath is what cracks and allows it to expand in diameter which allows the rollers to slip badly. Again, this might not be the cause of the noise, but unless every single part is carefully and thoroughly inspected, you can't rule it out
I suppose once I remove the rotor, I could install it without all of the starter motor components by using the kick starter, I figure if it functions without making the noise again, and without throwing the kick start lever back up, then we’ll know that the starter clutch is indeed the culprit. Do y’all think that would be a good idea?
 
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