Clutch or trans?

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SteveD
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Re: Clutch or trans?

Post by SteveD »

Finally got the trans back in and everything buttoned up. Trans feels great, clutch felt fine but it rattles like the noisiest camchain you've ever heard. It's not the camchain, definitely the clutch. So, it'll all come out again I suppose.
Cheers, Steve
Victoria, S.E.Oz.


1982 R100RSR100RS supergallery. https://boxerboy81.smugmug.com/R100RS
2006 K1200R.
1994 R1100GS.
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gspd
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Re: Clutch or trans?

Post by gspd »

steveD said "it rattles like the noisiest camchain you've ever heard. It's not the camchain, definitely the clutch."

Does it stop rattling when you pull the clutch lever in?
Mechanic from Hell
"I remember every raging second of it...
My bike was on fire, the road was on fire, and I was on fire.
It was the best ride ever!"
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SteveD
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Re: Clutch or trans?

Post by SteveD »

gspd wrote: Sat Dec 12, 2020 11:32 am steveD said "it rattles like the noisiest camchain you've ever heard. It's not the camchain, definitely the clutch."

Does it stop rattling when you pull the clutch lever in?
Yes it does.
When riding it feels fine, changes well, lever feels good.
Cheers, Steve
Victoria, S.E.Oz.


1982 R100RSR100RS supergallery. https://boxerboy81.smugmug.com/R100RS
2006 K1200R.
1994 R1100GS.
Rob Frankham
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Re: Clutch or trans?

Post by Rob Frankham »

SteveD wrote: Tue Dec 15, 2020 4:03 am
gspd wrote: Sat Dec 12, 2020 11:32 am steveD said "it rattles like the noisiest camchain you've ever heard. It's not the camchain, definitely the clutch."

Does it stop rattling when you pull the clutch lever in?
Yes it does.
When riding it feels fine, changes well, lever feels good.
Further to the question above, when you take up the slack on the clutch lever without actually pulling the clutch in, does the noise stop or change in anyway? That may indicate the difference between problems with the clutch release bearings and problems with the bearings in the box.

Also, is the noise the same in all gears?

You can make an awful lot of inferences from what noises the box makes, when it makes them and under what circumstances...

Rob
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gspd
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Re: Clutch or trans?

Post by gspd »

steveD said: "When riding it feels fine, changes well, lever feels good."

Sorry, impossible to diagnose without hearing the bike in person.
One of the most frequently asked questions in my decades of airhead repairs is: "My bike is noisy in neutral with the clutch out, but quiet with the clutch in, is this normal?

Keep in mind, every vehicle that has a clutch sounds a bit (or a lot) different when the clutch is engaged/disengaged in neutral.
Noisy with the clutch lever pulled in (or pedal down) is usually the release bearing.
The usual culprits if the noise is REALLY pronounced, even after a good run, are worn clutch disc/input shaft splines, or excess play in the input shaft bearings/shims.

I remember when un-crating and PDI-ing brand new airheads, the degree and intensity of the clutch sound/noise with the clutch released varied from barely perceptible to obnoxiously loud and annoying from bike to bike. Even the noisiest ones were ultimately delivered to the buyer, who didn't notice (or didn't care) about the noise. The customers that inquired about wether or not it was normal were told to put some miles on it and it would 'smooth out". Many times, the "noise" could be greatly reduced with carb synchronization and idle speed adjustments. BTW- that's when I discovered that a little 'by ear' carb tweaking can provide smoother and quieter running engine than most vac gauge/tachometer combinations. Sometimes the "quiet" solution was simply an 'out of spec' 1100 rpm idle instead of the recommended 950-1050.
Mechanic from Hell
"I remember every raging second of it...
My bike was on fire, the road was on fire, and I was on fire.
It was the best ride ever!"
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SteveD
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Re: Clutch or trans?

Post by SteveD »

Thanks gspd. The idle/tune is incomplete and I'm aware this may be a contribution.
Whilst the bike was laid up I also raised the needles from 3rd to 2nd notch, I've ensured the idle mixture screw airways are clear. O-rings good.
It needs a decent tune still. I just haven't had time leading towards xmas. It wasn't this noisy previously.

Fwiw, here's a video..https://photos.smugmug.com/Gearbox/i-6C ... 83-640.mp4.
Cheers, Steve
Victoria, S.E.Oz.


1982 R100RSR100RS supergallery. https://boxerboy81.smugmug.com/R100RS
2006 K1200R.
1994 R1100GS.
PAS
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Re: Clutch or trans?

Post by PAS »

I say it's the gears clacking at idle.
Rob Frankham
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Re: Clutch or trans?

Post by Rob Frankham »

Hmmm, doesn't sound good to me... A couple of other things I'd like to know...

Does it happen when the bike is being ridden on the road?

Does it happen when the bike is in gear on the main stand ?

Does it happen in all gears or just in neutral (and if it does, is it the same in all gears)?

Does applying pressure to the gear lever affect it in any way?

Rob
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SteveD
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Re: Clutch or trans?

Post by SteveD »

Rob Frankham wrote: Thu Dec 17, 2020 5:40 am Hmmm, doesn't sound good to me... A couple of other things I'd like to know...
Thanks Rob.
Does it happen when the bike is being ridden on the road?
Riding the bike the clutch feels fine and the gears change nicely. No noises that I can hear until it's clacking away at idle.
Does it happen when the bike is in gear on the main stand ?

Does it happen in all gears or just in neutral (and if it does, is it the same in all gears)?

Does applying pressure to the gear lever affect it in any way?
I'll check tomorrow. I plan to warm it up, try and tune the carbs then change the oil out.
I have Penrite semi-synth 75W-90 in there just now. Once the carbs are done I'll assess then do an oil change. I have some 80w-140 I'll try to see if it helps quieten it a little but hoping the carb balance will sort it.


Rob
With Xmas upon us, night shift this week and a backyard building project I need to finish up, this has been back in the line.
Cheers, Steve
Victoria, S.E.Oz.


1982 R100RSR100RS supergallery. https://boxerboy81.smugmug.com/R100RS
2006 K1200R.
1994 R1100GS.
Rob Frankham
Posts: 1214
Joined: Thu Aug 26, 2010 2:11 pm
Location: Scotland UK, 20 miles from civilisation up a dead end road!
Contact:

Re: Clutch or trans?

Post by Rob Frankham »

75W-90 should be fine but it should be GL-5 spec not GL-4.... not that I think it has much to do with this problem. FWIW, I would avopid moving too far away from the BMW approved oil spec (80W 90 GL-5). Making it last is more im portant than making it quiet

If you can be sure the noise stops when you are moving, that tends to lean towards the unloaded gears moving about... a good balance may help but I'll look forward to the other results before making a decision as to ehat I think is going on...

Rob
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