e50 high pitched ringing noise

Hey folks, I've got a Swinger II with and e50 and this high pitched ringing noise has been bothering me since I restored it 2 years ago. From what I remember, I replaced all the bearings and seals. I'm thinking it could be any of the following: worn gears, worn bearings, worn brass bushing, or an air leak somewhere. Bike is all stock except hi flow air filter from treats and a larger jet (probably too large). I noticed some oil on the underside of the engine so I may need a new exhaust gasket. My friend has the exact same moped as me, with his being 100% stock, and his sounds much quieter with no ringing/whistling/whining whatsoever. I've attached two videos of the sound, one with the bike stationary and one in motion with the camera in a backpack. You start to hear the sound at about 0:26 in the video.

Thanks for your time, guys.

Re: e50 high pitched ringing noise

Overpriced Parts /

Tire rubbing

Re: e50 high pitched ringing noise

Thanks for your reply. I don't see any evidence of tire rubbing, but I do have the fattest rear tire I could find stuck onto the back. I'll see if I can temporarily swap rear wheels with my buddy because he has the skinny tires.

Also, is the brass bushing on the clutch bell supposed to spin on both surfaces?

Re: e50 high pitched ringing noise

I adjusted the tire so that I know it's rubbing, and it made a different noise. Does the tea-kettle like noise sound like an exhaust leak? I never replaced the header gasket and it could be not very good.

Re: e50 high pitched ringing noise

Alright I replaced the top end gaskets and the crank/clutch brass bushing with a tighter one and it still sounds and performs exactly the same. I only hear the whining when the clutch comes on and the rear wheel starts turning. It's the original 2 shoe clutch from 1978. Could the noise be some kind of clutch slippage/vibration?

I also don't hear it if I pedal the bike with the engine off at ~20mph, but when I run it at ~20mph, it's there.

Re: e50 high pitched ringing noise

Bearings on your crank. When you petal it does not spin your crank. So I'm guessing when it is running it is probably bad bearings you are hearing.

Re: e50 high pitched ringing noise

Thanks for your reply, Sam. It's possible I forgot to change one of the bearings when I rebuilt the bike a few years ago. It's a pretty big job to drop the engine and split the case to check out the bearings, but I'll see if I can get to it sometime soon. Could is also just be the sound of the gears meshing? They are a little worn.

Re: e50 high pitched ringing noise

You have trans fluid in there?

Re: e50 high pitched ringing noise

how do you hit 20mph pedaling a moped

Re: e50 high pitched ringing noise

-Owen: Yes, Type F.

-Simon: Down a hill. (edited)

Re: e50 high pitched ringing noise

To me it sounds like the beautiful whirring tone that an e-50 transmission countershaft makes. Some are louder, some are not as loud, It sounds like music to me...Try some SAE 30 w motor oil.

Re: e50 high pitched ringing noise

Bobby, thanks for your reply.

I agree the noise can sound interesting, but it just gets deafening at high speeds. Much louder than the exhaust note. I put in some heavy motor oil and it may have gotten a bit quieter (or that's just my imagination), but the noise remains at high speeds. I'll likely open it up and check out the bottom end over the weekend.

Re: e50 high pitched ringing noise

Michael Coonan /

I agree with Bobby. One of my Free Spirits has made the same noise for 5 years, while my other doesn't. Post back if it turns out to be something else. It would be interesting if my shit is broke but has been running this whole time.

Re: e50 high pitched ringing noise

I tried a little experiment by starting the bike up and removing the chain while it idles. Then I revved it with the engine not connected to the rear wheel and the high pitched noise was gone. I also tried moving the rear wheel fast with the pedals and that was silent. That makes the think my chain is worn or could be causing a vibration. Either that or the wheel causes drag to torque the gears enough to be misaligned. I'll see if I can get my buddy with the quiet moped to swap chains.

Re: e50 high pitched ringing noise

The extra load on the countershaft is what makes the whining sound.

Re: e50 high pitched ringing noise

My e50 made that exact noise. It was not pleasant. Nor did it ever go away. It was rebuilt engine, stock crank too.

Re: e50 high pitched ringing noise

Thanks for your reply, Bobby.

Would you say it's from the countershaft bearings or worn gears?

Re: e50 high pitched ringing noise

If you get a loud pipe you'll never hear it again. I would'nt worry about it.

Re: e50 high pitched ringing noise

I was fixing a bike for a friend, and had a very similar sound coming from the bottom end, turns out it was the drive gear's bearings, id say just get new bearings and forget about it.

Re: e50 high pitched ringing noise

Yep, I would replace the bearings and seal on the main gear. That should resolve the problem. Remember to grab a new gasket set while you're at it.

Re: e50 high pitched ringing noise

Thanks for your replies. I'll plan on changing the bearings when I have enough free time and space. I read that running with your chain too tight will prematurely wear your bottom end bearings, and that could be a possibility.

Re: e50 high pitched ringing noise

♣Slew Foot♣ /

if you are going that far, replace the conrod bottom bearing. you would kick yourself if you put it all back and whirrrrrrrr, check that your speedo isn't pinned at 40. it whirrs

Re: e50 high pitched ringing noise

Okay I've started working on my engine. I dropped it and am getting ready to split the cases once I can find some screws to pull the flywheel. I noticed quite a bit of lateral play in the flywheel. Maybe like an eighth of an inch side to side/up and down. That makes it seem like the crank bearings are no good.

Once I get it apart, I'm planning on changing all four bearings and seals. Maybe a new chain too, since my chain is the original one and it rattles when I wiggle it side to side.

Thanks for your help, guys.

Re: e50 high pitched ringing noise

Michael Coonan /

Let me know how it turns out. Good luck!!

Re: e50 high pitched ringing noise

sounds like bearing to me, but not on the bike. Have you checked and repacked the back wheel?

Re: e50 high pitched ringing noise

Alright I got new bearings and seals in. The two on the main gear were original and felt pretty rough. And one on the crank could actually spin relative to the case. I got it all back together and the noise is still there. It might be quieter or it's my imagination.

My chain is original and worn pretty badly, so that's the next thing I'm going to check.

Peter, the back wheel spins easily and quietly with the drive chain off the bike. I don't think that could be a problem, but it's worth checking out if a new chain doesn't make a difference.

Re: e50 high pitched ringing noise

Bearings often make thier loudest noises under load. Based one your description I would say check the alignment between the front and rear sprockets. Chains do not like to bend axially. If the alignment is off you are adding unusual loads to that system, which could make any of those pieces in that system noisey. Check with string.

Also, those loose axle bearings need to be inspected when serviced. Freshly greased but galled and pitted ball bearings will be noisey still.

Re: e50 high pitched ringing noise

Michael Coonan /

This might be redundant, but did you pull the clutch out and inspect everything?

Re: e50 high pitched ringing noise

It's possible that I could have misaligned my sprocket and rear wheel. I've had the wheel off multiple times. I'll take a look at my buddy's identical bike and see if I got the shims in the right place. Thanks for your reply.

Re: e50 high pitched ringing noise

It's the 2 shoe original clutch and it still has quite a bit of material on it. Could it be possible for the old material to be slipping against the bell and making a noise?

The performance seems to be okay. Really sluggish off the line, but it can hit 28-30.

Want to post in this forum? We'd love to have you join the discussion, but first:

Login or Create Account