What is this Sound?
What is this Sound?attached is a recent sound coming from my 64 superhawk. it only happens after the bike warms up. it seems to be coming from the right side. and goes away when the engine is revving or under load. at idle it becomes very noticeable. it sounds like a dangling spoon bouncing off a rotating fan. is this a wrist pin problem, a cam chain problem or something else all together? any help would be greatly appreciated.
thanks http://fcinternet.hwdsb.on.ca/~mark.had ... =S02C43DC9 go here and click on bad bike sound.mp3.mp3 the sound is evident 1/3 of the way into the sound clip thanks
Hey Mark,
That doesn't sound like wrist pin noise to me -- I have knackered small ends at the moment and the sound is of a much lower frequency, being unapparent at idle, but evoking from a light throttle application past 4k rpm. Unless you have access to a medic's or a mechanic's stethoscope, use a long screwdriver to pinpoint the source of the noise; start from the top and work your way down. With the motor running hold the 'driver tip hard against an unpainted portion of the castings, casings or a screw-head (so as not to inflict any damage) and stick your ear against the end of the handle; as you move the tip around you'll notice where the sound is more or less apparent. That's a good starting point. I'm inclined to agree with Joe's stab at identifying the noise: it sounds like the starter clutch components to me. Those 3 rollers get compressed against their respective pushrod/spring combos when the rotor spins and it sounds as though one of them is snagging or snapping back out into its cave. I don't know if they should be dry or lubed, as I have a problem here myself at the moment whereby my starter won't catch at all -- I've cleaned out the dust & crud from the 3 caves and pushrod channels and dried it all out -- but I reckon Ed will provide the definitive answer before the next 24 passes....... The clutch/rotor is easy to eliminate: remove the rotor from the 'shaft and run the motor. Don't leave the Woodruff key in place during this process as, at best you could lose it or, at worst it could cause physical damage (to you or the stator) if it flings out. We're all interested to know the next installment..... Regards to all, Steve
Re: What is this Sound?The cam sprocket is held in place with the cam spline part with 4 sort of rivets. Not uncommon for the sprocket to loosen and you hear that noise at idle. If you are careful you can compress the rivets but it's possible to cant one of the two which are the shafts for the points advancers and lock them up. Also a shop with a wire feed welder can tac weld the parts together but be careful to not melt the neoprene on the advancers. If the neoprene is gone one one or both of the advancers you can also get that sound. .....................lm
RIDE IT DON'T HIDE IT!
SOLVED
it was the starter clutch screws. the ones that screw the starter clutch onto the stator. 2 of the 3 screws were loose, one was bent and ground down pretty good. i removed the starter clutch and checked the pins and springs, every thing was ok. i then screwed the clutch back onto the stator. i had to back up the starter chain to put it all back together. everything is fine now. the bike runs like a dream, i mean a superhawk. thank you all for the help. mark
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