Alarming intermittent sound from the Bassa

[normzone]

Hello all -

I'm eyeballs deep in a new job, and the bike has decided this is a good time to make my life even more interesting.

I first noticed this last night, when I shut the bike down at the grocery store - I thought I heard metal grinding, or maybe glass breaking. I turned the bike on and off again several times, but it did not repeat.

When I got home and shut it down it happened again - a grinding sound at shut down. Again, cycled the bike a few times and it did not repeat.

This morning it did it a couple of times on the way to the onramp - just for a second. Then once more at freeway speeds, but did not repeat until shutdown when I got to work - a grinding sound.

I checked oil this morning, all is good. My untrained ear wants to say transmission, but that makes no sense, as that should be constant, not intermittent. Same with timing chain to my way of thinking, but you know how reliable that is.

Is this a known symptom with a definable fix, or am I entering into uncharted waters?

Thanks all for everything you do to keep me sane ... 

[fotoguzzi]

Get some ear plugs🙂

[oldbike54]

 Am I understanding this , it is making a grinding sound after everything is shut off ? Is this happening after the engine is completely stopped and all forward motion has ceased ?

 Dusty

[yogidozer]

timing chain? maybe if you could get a recording?

[Wayne Orwig]

Broken clutch plate rattling around.

Maybe something (pinched wire, tank bag?) is engaging the starter.

[Chuck in Indiana]

I thought I heard metal grinding, or maybe glass breaking.

Well, that certainly narrows it down.. 

or am I entering into uncharted waters?

Beyond here be dragons..
 

[normzone]

Get some ear plugs🙂

I've been riding with earplugs since the first time you guys talked me past getting used to the engine - left them out on a short errand the other day and scared the hell out of myself by bumping the horn button.

Dusty, it's done it both while in motion, and as I turn the key off and it takes it's final breath of the run and the engine stops.

Which makes me wonder about the broken clutch plate theory ... I guess the next question is this a STOP RIDING IMMEDIATELY issue, or is it a RIDE IT UNTIL IT BREAKS so I can be sure what is broken.

A recording? Well, I was considering a trip to Frys - too bad the credit card is so tired, but that might be necessary.

I gave up my laptop virginity today - life can be so variable.

[John A]

What Wayne says

[oldbike54]

 It does sound like a clutch problem , and yes , stop riding it until it is fixed .

 Dusty

[guzzisteve]

When you shut it down was clutch out and in neutral or clutch pulled in/in 1st? Just to clarify the engagement.

[rodekyll]

Maybe pull the starter and take a look at it and what's inside the bell housing.  You might spot a broken bolt head or a bad starter pinion.

[normzone]

When you shut it down was clutch out and in neutral or clutch pulled in/in 1st? Just to clarify the engagement.

Clutch out and in neutral.

[Wayne Orwig]

Clutch out and in neutral.

But you also said:

This morning it did it a couple of times on the way to the onramp - just for a second. Then once more at freeway speeds, but did not repeat until shutdown when I got to work - a grinding sound.


So it does it in gear also, right.

[guzzisteve]

If you drain the trans oil and see no metal, it's the clutch, just like Wayne said.

[fotoguzzi]

how does the clutch feel ?

[normzone]

No problems, works just fine.

[normzone]

Update - on my way home today it gave a big squeal shifting first into second - only that once.

I got helmet off and earplugs out before shutting it down, listened all over and then turned the key off.

The transmission (I think) made a sound somewhere between an animal growling and some big spring being wound up.

Perhaps I can pay for my repair by marketing a book of descriptions for engine sounds, with a diagnosis flowchart.

And sometimes the shift lever reminds me of when the return pawl spring (?) broke on my Eldo - excess play in the resting position. BUT NOT ALL THE TIME !

The question still remains, ride it till it 'splodes or take it to a trusted wrench and hand them my credit card. I know it's an open ended can of worms once you go down that  road - pull and open gearbox, eval and repair, update other widgets while in there. And do you do the clutch while you're there, at only about 70K miles?

Or do I shop for another late nineties bike? I really need to win the lottery ....

[lucian]

Is it possible that the starter gear is not disengaging?

[John A]

Do the kickstand springs rub on the left header pipe?

[rodekyll]

Or maybe the throw out rod end or bearing?

[fotoguzzi]

Or do I shop for another late nineties bike?

are you too Macho to ride a Vespa? could probably trade that junker for a nice 250cc ..

or get a DR650 old school and bullet proof..

[Tom H]

As mentioned, I would change the gearbox oil with the engine warm and sift through the oil for bit's of metal or plastic, as in plastic bearing cage bits.

Remembering where you have to work on the bike, you may now have reasonably determined the problem and need to take it to a shop. Or as the least gave it a good whirl and still need to take it to a shop to find out whats wrong.

From your description, it does not happen when you hit the starter. It also does not continually make the noise. To me, that kinda rules out the starter. But, if it makes the noises while slowing to a stop, it could be an issue with the starter bendix hitting the ring gear??

I have not delved deeper into my EV Touring engine than replacing a rear trans seal. That was a bunch of bits to remove. But if we were closer and you had the time, I would offer my garage for a tear down to get to the clutch and at least have the gearbox out to take it to someone that knows how to work on a gearbox.

Sorry I can't be of more help!
Tom

[John A]

Eliminate the dozens of places that noises come from. A short list is header pipes, broken crossover , mufflers, slap the end of the mufflers and listen,frame rail covers, plastic chrome on fenders, kickstand, center stand , tank,well you get the idea and you wouldn't want to pay a shop to check that sort of stuff for you

[Zoom Zoom]

If you're able to replicate the noise while stopped, you might consider getting a mechanics stethoscope and listen at various locations to try and locate the source of the noise. They're not too expensive.

Just a thought.

John Henry

[normzone]

I have considered starting it without the starter mounted via the hill I'm on and riding it around to see if the sound replicates.

Worst case scenario I'd have to carry the starter and tools to remount it with me in case I stalled it or got stupid and shut it off.

I guess this weekend is evalution and tinkering.

[ccoli]

I'm going to vote, broken clutch plate. Whirring sound is the inner splines grinding away  the front of the transmission housing.  Won't do too much irreversible  damage. Could provide pictures if that would be helpful. 
 Maybe you could flush the bellhousing with mineral spirits and check for aluminum dust in the drainings.

[fotoguzzi]

How many miles? I would check all John A’s suggestion s before worrying about the clutch.

[normzone]

Approximately 70K miles - I will check all that stuff this weekend.

I spent all night convincing myself it was the starter, but again today leaving a stoplight after getting all warmed up on the way to work, a shift up into second yielded the sound of a bullet ricocheting off a rock. Nice clean shift on my part, no logical reason for that in my mind.

I'll drain and eyeball gearbox oil Sunday.

[scra99tch]

Pressure release valve groaning?

[acogoff]

     An improperly shimmed mainshaft in the transmission(way loose), eventually allows the radial thrust bearing to start shedding rollers that proceed to run through gears. Intermittent crunching. If this is occurring, you will find evidence when you drain your transmission. Hope this is not your problem.