engine whining when revving up? Help

hi yamabob83 , that sounds a lot like the sound i had on my bike, it also sounds like the sound i heard on a youtube clip of a xs with a bad starter gear ( #4 ) i think i looked again but cant find it .I was sure mine was a starter gear not disengaging but mine ended up being that front can chain guide it had just started wearing in to the aluminum. p1010668 (Modified in GIMP Image Editor) (Modified in GIMP Image Editor).jpg

not sure ???????
peace
 
Alright i found that video on you tube it is an 83 xs too. The guys on there are saying it is the one way gear that is used for the electric start since i will not be using electric start can i just remove it? I think that is my sound
 

Her is the link to the other guys bike that sounds like mine it is as well a 83 xs. His is alot worse than mine but same sound let me know what you guys think.

Thanks
 
Certainly sounds similar. Does your electric starter work? When the motor starts running it's supposed to overtake the starter and spin a starter shaft back inward and out of engagement (my understanding of how it works). There are lots of threads on getting to the starter to fix the typical grinding noise it makes. Involves removing the clutch plates to get to it, which isn't difficult if you can round up an essential but rare tool to keep the clutch from turning with the nut (my limited understanding again). You can bump it briefly with the cover off and no oil, to see what's happening with the starter.
 
Have you pulled the lower oil filter out and looked for debris? To me it sounds like the cam chain guides are worn out. If so, you will have plastic and probably aluminum bits in the bottom fof the crank.
 
I haven't checked that yet but when i pulled off the valve covers there was some shredded up what looked like and felt like silicone or gasket material could have been pieces from the cam chain guide though i don't know it was built up around the rubber o-ring that seals the little caps.
Anybody else recognize this noise the noise on you tube on the other bike is the closest i have heard and his problem was the electric starter gear #4.

Thanks
 
Alright i took all the unnecessary gears off of the shaft behind the clutch plates for the electric starter. Filled her back up with oil and it is still making the same sound. Now What? Should i take the top end apart and check the cam chain guides? My buddy listened to me ride it down the road today and he said that's all he could hear when i was out of sight was the whining noise like a supercharger. Anybody think that it could be the main bearings on the crank or is that unlikely. I also messed with the cam chain tensioner while it was running today and either way i turned it it didn't get better or worse.

Anybody have a motor with the same ignition as mine that they want to get rid of??? I'm running out of options.

Thanks Guys
Remember the video with the sound is earlier in the thread.
 
yamabob - thanks for the PM directing me to this thread. I had the exact same noise with my bike. I am still not sure if it was an overtightend cam chain or bad cam bearings because my project got bigger. I didn't have any plastic pieces from the cam chain guide or tensioner in my oil filter, but I also didn't tension my cam chain with the engine hot.

I ended up dropping my engine and popping the top off and sliding off the cam bearings. These need replacement or at a minimum solvent cleaning. Rolling my bearings by hand wasn't rough, but had a lot of friction. I'm thinking they sat too long without running/getting oil.

There is plenty of advise on adjusting the cam chain tensioner with engine hot on this site. I'd try that first. If it doesn't work, replace the cam bearings. Thanks to advise I got here, I know it can be done without breaking the cam chain. If I didn't have more work to do with my engine, I would have had the engine out, bearings changed and engine back in over probably three to four hours.

BTW, nice bobber!
 
nj1639 i have not yet checked the bottom strainer or the right side oil strainer. I have however had the whole side cover off and have drained the oil to do this, i didn't see anything in the oil on either occasion do i still need to pull the filters?
 
Ludlow so you listened to the video and that's the same sound you were having before you changed the cam bearings? it is very loud when under load and driving as i described in the above post. I will just get the cam bearings and pull the motor and change them if you think that is what it is. At any rate it will at least eliminate another possibility.

Thanks for everybody's help so far by the way.
 
The side strainer'll show debris in the wire mesh, if there's any metal check it with a magnet to see if it's steel or aluminum. Popping the side cover off the right side will drain the oil out but possibly not as thoroughly as removing the sump plate. There's 3 magnets on the bottom of the engine, 1 in each drain plug and one on the sump, found a cam chain side plate link attached to the magnet on the sump of one engine, oops po!. Good idea to check them all. Doesn't cost anything to check....carefull with the sump bolts.
Cam chain is adjusted when running temp is achieved, good point on the cam bearing possibility.
 
Every time that i have changed the oil out of it the drain plugs have a small amount of shavings on them but i didn't think it was enough to worry about maybe it is.
 
It definately a rotational noise as it gets a higher pitch when the rpms are increased. I'd have to believe the upper cam bearings would starve for oil before the lower crank bearing would but this is all guess work since I've never heard that noise from an XS.

Just thought of someting. If the starter return spring is old or damaged and not disengaging that might also make a whinning noise. Sorry I'm not much help I'm just spilt balling things here. An elcheapo mechanics stethoscope would pinpoint it the best.
 
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I would definetly check the oil filter and the magnets first - that's way simpler than dropping the engine to pull the cam cap off for the bearing swap. Mine has a cracked case so I'm going all the way. Also, I checked for the plastic chunks first and found none. That doesn't mean my cam chain wasn't over tensioned, it just means the guide and tensioner didn't come apart yet.

All the advice here makes sense. The screaming is relative to the rpm, so it is related to rotation. If it's coming out of the top or front of the engine, it is either the cam chain (metal to meatal contact - plastic chunks in the oil filter) or cam bearings. Nothing else up there is turning constantly.

My bike started making that noise on my way home from work and got louder and louder. It really freaked me out. I had only been riding it for three days since I got the paint work done and got her running. Before that it had been sitting in a barn for 20+ years. When I got home I started looking and asking questions like you are. That was over a month ago. Now I'm trying to find a good replacement case and I'm committed (or should be) to this project for a while. Might as well make it right now that she's pretty.

BTW, my wife is pissed at my investment - so much for saving gas. I guess that gaurentees more time in the garage. Oh, marital bliss...
 
Alright i got the motor torn down this morning and the pic of the chain guide above looks to be my problem. It is starting to wear into the aluminum at the top of the guide and the plastic piece is almost ready to come all the way off of the aluminum itself. It has cracked all the way down the right side. I am hoping this is my problem. Everything else looks to be in good shape. There is no way to take out and replace the other chain guide unless you completely tear the motor down is there??? I can only hope that when i replace that chain guide that my sound is gone. Thanks for everyones help on this problem cant thank you enough.
Any other suggestions while i have this thing tore apart would be great also.

Peace
Eric
 

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