I finally got my R65 Ls out of the basement after taking off the whole rear end o clean it up and paint it after winter riding left it a bit rusty. The only engine work I did was lubing the clutch splines.
The other day I took it for a short spin to get gas. About 13 km's in I heard a horrible screaming. Thinking wheel bearings I stopped and had a look and they seemed ok. I got home without much more bad noise and pulled the front wheel to have a look.
Bearing were fine so put the wheel back on. I started it again and immediately it started screaming again and now I could tell the noise was coming from the cylinders.
Obviously I checked the oil first and that was not the issue. I haven't touched anything else on the engine. Anyone have any thoughts for me?
thanks
Rocker shafts and needle rollers ??
If you had not said the cylinders, then I would have looked at the speedometer drive cable, the instrument heads, or something under the front engine cover. Those are areas that have "spinning" items more prone to squeal.
Owning an old Airhead is easy.
Keeping an old Airhead running great is the true test.
Worth having a look under there too as I was messing with the contacts to the stator and I replaced the control unit. Maybe I bumped something? I should do that asap as we're under fire alert for a wildfire that's headed our way and I want to evacuate the 3 bikes I have here if we have to run.
Looked under the front cover and it's definitely nothing there. I'll pull off valve covers and see what It see.
Problem solved! It turns out it was the transmission screaming at me because some idiot forgot to replace all the oils when the rear end was put back on. Startup sounded oh so good after a fillup. I guess we'll see down the road how much damage I may have done.
I went to check the valves but damned if I could find the "OT" for TDC. I may get back into it today to try again but if I remember correctly it wasn't very long ago that I did the last check.
Problem solved! It turns out it was the transmission screaming at me because some idiot forgot to replace all the oils when the rear end was put back on. Startup sounded oh so good after a fillup. I guess we'll see down the road how much damage I may have done.
Oh, gosh ! That can't be good.
I went to check the valves but damned if I could find the "OT" for TDC. I may get back into it today to try again but if I remember correctly, it wasn't very long ago that I did the last check.
Since the plugs are out for turning the engine by rotating the rear wheel, just place a screwdriver down the plug hole and guide it as it is forced out by the rising piston. TDC for valve lash adjustment doesn't have to be EXACTLY on the mark like ignition timing does. Anywhere close is good enough. If the piston is within +/-10° of exact TDC, remember the camshaft turns at half the rate of the crank, meaning the cam position is within +/-5°.
With the pistons near TDC, due to the offset position of the cam lobes, one set of rocker arms will be tight (Cyl B) and one set will be loose (Cyl A). Adjust the clearance on the LOOSE set.
Then rotate the rear wheel until the crank is rotated 360° and the next TDC is found. At that point the camshaft will have rotated 180° and rocker arm conditions will have reversed. Then you can adjust the valve lash on the opposite cylinder.
Owning an old Airhead is easy.
Keeping an old Airhead running great is the true test.
That's some excellent info and makes it very clear for figuring out both sides. If I'd been thinking clearly I'd know for checking the pistons as that's what I have to do for my KTM's but singles are a little simpler that way.
I think you would be well advised to keep on the look out for another transmission.
former Airmarshal, IL.
I'll wait and see how the current one runs before I get into that heavy a fix.
Once when I was a Honda dealership mechanic, I had a customer bring in his K5 Honda 750/4 with a audible gearbox squeal/whine. I looked at everything and couldn't find it. Changed all the bearings and still couldn't find it.
Luckily, that same week a guy with the same model Honda came in for a gearbox job (he had blown out 2nd gear while street racing). His bike had straight pipes. To get an effective cure, I simply swapped both gear sets complete between the 2 bikes. The rider with the straight pipes couldn't even hear the persistent gearbox noise. The rider who could, got a nice quiet gearbox.
All 3 of us were very happy. 🤣
Owning an old Airhead is easy.
Keeping an old Airhead running great is the true test.
Good story, I need to get my back tire done again as I screwed up that up too.
A long time ago, I did a Level 2 on my G/S and went for a ride. About 15 miles later, I heard the squeal of something down there.
Back to the shop, bike on the lift, and I found out I hadn't tightened the tranny drain bolt, and it had wiggled out. Dumped all the fluid. Surprised I didn't slide out.
My bike, my mistake. I popped the cover off, and everything inside was black from the heat, but it turned like new once it cooled down.
Cover back on, installed, filled with Amsoil..and rode it another 50K miles before it came apart for a tall 5th gear.
Sometimes you get lucky.
Thanks for that insight. Here's hoping I'm that lucky.
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