What is this raspy engine noise? (sudden)

JayR

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Hi Forum members!

If you have 8 seconds can you listen to this engine noise and lmk if you have any ideas on what might be the cause?

It appeared suddenly on a ride. I then changed the oil, and adjusted cam chAin tensioner but the noise is the same.

What I did before the noise appeared:
new stator, rewired a burnt electrical harness. The bike was running best it ever had for about 100 miles.

Top end rebuilt 1,200 miles ago including cam chain tensioner.

I’m at a loss with this one - I am hobbyist, but just looking for a likely place to start investigating to try and fix the problem.

Thanks! Jay
 
Sounds like a very loose tappet. But I expect the experts will give better guidance based on great experience of these bikes.
 
I would check to make sure you lined up the stator and alternator correctly. The stator has a key piece and the alternator has a slot in the bottom that lines up with a pin. If all that is good then maybe the cam chain guide is too tight; It is ticking away pretty good. Oh and maybe it is a cam bearing; Misaligned or bad. Whatever it is I wouldn’t run it until you find out what you put together wrong.
 
Could be a separating crank. Take of the little alternator cover look closely for anything wobbling. Then look at the right side, turning it with the starter motor.

It started during a ride but did it start after you started it up during the ride? Was there a loud sound like the starter caught funny?
 
Are you talking about the ticking (tappets or cam chain) or the whining sound?
Hi Downeaster - yes I am referring to the whining sound, like a drowning cat. Agree that I do need to adjust the tappets because they are too noisy.
 
Could be a separating crank. Take of the little alternator cover look closely for anything wobbling. Then look at the right side, turning it with the starter motor.

It started during a ride but did it start after you started it up during the ride? Was there a loud sound like the starter caught funny?

Hi XJ - so it started mid-ride, not upon start up. It was definitely a bright line and noticeable change. I ride home directly after that. I’ll check for signs of a separating crank and do some more resewrxh. Thx k you.
 
I would check to make sure you lined up the stator and alternator correctly. The stator has a key piece and the alternator has a slot in the bottom that lines up with a pin. If all that is good then maybe the cam chain guide is too tight; It is ticking away pretty good. Oh and maybe it is a cam bearing; Misaligned or bad. Whatever it is I wouldn’t run it until you find out what you put together wrong.
Thanks bushyeye I’ll double check that too.
 
Sounds like a very loose tappet. But I expect the experts will give better guidance based on great experience of these bikes.
Yes agreed the tappets need some tlc, that was next on my list before this new issued popped up!
 
The whining is a new one on me, never heard that one before out of an XS. Sounds a little like gear whine to me, like something is too tight or not getting enough oil.

Might also be rotor/stator interference. Perhaps the rotor nut on the end of the crank came loose?

Complete disclosure: I'm guessing out my nether regions here, just throwing stuff at the wall to see if anything sticks.
 
The whining is a new one on me, never heard that one before out of an XS. Sounds a little like gear whine to me, like something is too tight or not getting enough oil.

Might also be rotor/stator interference. Perhaps the rotor nut on the end of the crank came loose?

Complete disclosure: I'm guessing out my nether regions here, just throwing stuff at the wall to see if anything sticks.
Haha disclaimer noted! Makes sense to start with what I changed most recently (stator). I read that somewhere on this forum. Thanks bud
 
It takes some attention to get it on right. Little slots have to line up or something, can't remember. Would be easy to have it cocked sideways.
 
its very difficult to form an opinion with such a very short clip. About 20 seconds would be much better for diagnosis.

have you tried to pinpoint which part of the engine /crankcase the noise is coming from ? You can use a long wooden rod or screwdriver placed in front of your ear against your skull .
 
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Fully agree with peanut - have used a long screwdriver as a 'stethoscope' in the past to pinpoint source of an engine noise. It can be scary at first to hear so much going on in there but then you start to isolate the rumbling of main bearings turning, the clatter of the valve gear etcetera.
 
So the stator and alternator are aligned correctly and the nut is secure. I have the small cam seal covers off and both sides look leaky. The cam shaft is not wobbly, and turns freely when in push the kick starter down. Maybe oil isn’t getting to the top of the motor. I’ll look around the site to see what to check.
 

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Are you making progress? You didn't check the right side of the crank for wobbling did you? The whine is exactly like what mine was doing, and it was the right side wobbling (bigly). The left side looked fine.

Front rubber off could probably make similar sound. Does the whining sound change if you lean the bike way over? Can cause chain to flex and rub side of the guide.
 
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Are you making progress? You didn't check the right side of the crank for wobbling did you? The whine is exactly like what mine was doing, and it was the right side wobbling (bigly). The left side looked fine.

Front rubber off could probably make similar sound. Does the whining sound change if you lean the bike way over? Can cause chain to flex and rub side of the guide.
Hi XJ apologies for the delay. Back-to-School week for my boys.

But I worked on the bike Saturday and a couple things you said struck home. Since it seems you experienced the same awful whining, how’d you fix it? Here’s what I did:

The cam shaft is not loose. I took the covers off each side and tried to wiggle. No wiggle. I even carefully put a small wood dowel inside and jiggled it to see if there was any play, none at all.

You said something about the starter clanging or sounding like it was catching a tooth upon start up after the Whining sound occurred. So this definitely happened on Saturday with my test start. My starters always been a bit weak, but it definitely made a new crunch sound and it reminded me of your comment.

BUT I also rechecked the valve tappet clearances and the right intake was WAY off. It was probably about a 1/16” or even 3/32 gap. That was the gawd awful noise we all heard on my clip. So I reset it to 0.003 and it as quite in that department as ever.

And last - in the Spring before I fixed my charging system I adjusted the cam chain tensioner to within 1mm +\- action. Was all good since I had my cam chain guide replaced 1,500 miles ago. So after the whine suddenly appeared last month I checked the tension again and it was very loose. Far out of spec. So I had to tighten it a lot to get back to the 1mm action tolerance. Maybe my cam chain guide rubber fell off? But I changed the oil and didn’t see any rubber bits. Although there were a few aluminum shaving bits in the side oil filter.

Maybe the cam chain guide failed, threw the tensioner out of alignment, then caused the right intake tolerance to blow out...and then that caused the whining noise?

Did I mention I don’t know what I’m doing? :)

PS I did not do the lean over test yet.
 
You would have to pull the right side clutch cover to check the crank on the right side, not the cam cover.....s'alright, you may have found the culprit with that valve.

I'll add....Ya gotsta have the valve adjustment tool that holds the square top of the adjuster and then tighten that nut down good to hold the setting.......anything less may fail.
 
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