Clutch noise?

Older CBR600, lo-miles.

Engine warm, accelerate up hill, maybe 35 mph, in 3rd gear. Reach
top, dis-engage clutch, coast down hill in 3rd. with clutch lever
actuated. When I hunker down, I can hear a sort-of growling/grinding
noise.

This is "normal operating noise" for a bike with a wet clutch?

Willie

 

Wet clutch baskets will make a low frequency clattering clunking noise
at about 1/3 the engine RPM with the clutch lever OUT.

If you pull the clutch lever IN and the noise goes away, that's the
clutch basket
flopping around a liitle bit on its bearings which ride on the
transmission mainshaft.

If there is still a lot of clattering and clanking with the clutch
lever pulled IN all the way, the two other suspects are a loose or
worn out cam chain, or a starter clutch that's flopping around on its
shaft.

 

That'll be the chain and transmission.

It's not the clutch. Not if you have the lever pulled in..

 

Wrong again. Different type of noise entirely.

 

OK.

A 2nd scenario. I go out the garage, start the bike cold, hold the
clutch lever in whilst in neutral gear, hear a very similar sort-of
growling/grinding noise. By the time I roll the bike out the garage
(maybe 15 seconds), the noise stops. I always try to wait for this
before shifting to 1st gear (less clunk).

Normal clutch noise?

Thanks,
Wille

 

Hard to tell without listening, but all transmissions and clutches make
a noise somewhere or other. Just ride it. I don't think anything at all
is wrong with it.

 

As I said previously, the clutch basket itself has to ride on a
bearing that allows it to turn at a different speed from the
transmission mainshaft.

If this bearing is worn out, the clutch basket can flop around
radially and it will make a rattling sound until you pull the clutch
lever in.

Part of the noise is also due to slight misalignments of the primary
gears, which are usually straight cut gears.

Straight cut gears are generally noisy anyway.

If the big nut that holds the clutch center hub onto the transmission
mainshaft is really loose from drive train slop over the decades, the
clutch basket can also walk sideways, along the axis of the mainshaft.

Pulling the clutch lever on a Honda will usually push a loose clutch
center hub towards the centerline of the motorcycle, because the
clutch is build Honda-screwy, it's inside out, compared to Suzuki,
Yamaha, and some Kawasaki clutches.

Pushing on a loose clutch by pulling the clutch lever will quiet down
the clutch.

On Suzukis, Yamahas, and some Kawasakis, pulling the clutch lever will
push a loose clutch center hub away from the centerline of the
motorcycle, stopping some of the clutch rattle.

Then there is the transmission itself, which has 5 sets of noisy
straight cut gears, which are all meshed with each other, all the
time, even when the tranmission is in neutral.

These gear sets don't have any bearings inside the gears, so they tend
to be noisy when the engine is cold.

Also, cold engine oil is thicker than warm engine oil, so the gear
sets will try to turn the rear wheel, even when the transmission is in
neutral. It's the thick oil and high idle RPM when cold that causes
the transmission to clunk when you
put it in gear.

You might try putting the transmission into 2nd gear first, to reduce
the clunk, and then put it into 1st gear.

I wouldn't pay too much attention to "TOG", who calls himself "The
Older Gentleman".

He's not older, and he's NO gentleman. He hangs around on Usenet all
day to start arguments with people. He'll tell you that he's "just
trying to help", and that it's all your fault for being too stupid to
describe your problem accurately.

He will insult you and argue some more, and try to get you to admit
that you're the one who's wrong and you'll have to apologize for
"wasting" his time.

He's a Usenet troll, this is what he does all day.

 

Nope. He's just saying the guy doesn't have a problem. And he's just
said that all transmissions make a noise of one sort or another, only he
managed it in rather fewer words than you just have.

 

How do you KNOW that?

You don't KNOW whether he has a problem with cam chain tension, worn
out chain and sprockets, a loose clutch hub, bent shifter forks, or a
starter clutch that's about to lock up and throw him onto the
pavement.

You just don't KNOW.

But I think if you go over to ukrm, you can find a whole bunch of
Slimey supporters who will be glad to extend this thread to 90 or 100
off topic messages...

 

You're talking about one of the most tough and reliable[1] bikes that
Honda ever built. I'd roll with the percentages. The odds are that Mr
Honda got it right (because he does, mostly), you've got it wrong
(because you do, mostly), and he's worrying unduly (because a lot of
newbies do). So I'll say that none of the above is likely to "throw
him onto a pavement" any time soon.

If that does happen, though, I'll certainly apologise. Oh, and I
mentioned chain and sprocket noise ages ago. I see you've decided to
list it as a possible problem, at last.

[1] Second gear used to go on abused early ones. Reg/rec failure is
well documented, and not confined to the CBR6 anyway.

 

It's an OLD Honda, maybe 20 years old, and WHO knows what abuse it's
been exposed to?

Certainly not YOU.

A fat lot of good your apology will do him, if he has to take a ride
in an ambulance or has to pay a huge repair bill.

 

It's still incredibly tough, and I see and play with rather more old
Hondas (some much older than this) than you do, so I reckon I know a
bit more about 'em. It may indeed be on the brink of death-dealing
mechanical catastrophe, but I doubt it.

Still, carry on sounding your tocsin[1] if it makes you feel better.

As opposed to paying a huge bill to a mechanic to be told nothing's
wrong? Think DatesFat.

<Leans forward over desk conspiratorially>

Are you really warning him that his gear selector forks are bent and
about to kill him?

[1] You may need to look this up.

 

better.

You are dull and black, Mr. Pot, but I am becoming more and more
mirror-like with every passing day.

 

better.

You are dull and black, Mr. Pot, but I am becoming more and more
mirror-like with every passing day.

 

Take a hard look at the oil next time you change it,
looking for metal fuzz and powdered bronze. If you've
got an oil filter that can be opened, consider disecting
the filter too.

Tear into it if you see metal or if the noise gets louder.

 

You've seen such condition(s)? What caused it?

 

The only safe approach is to switch off the engine and use one of these...
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=120494732675.

Otherwise just ride the bloody thing.

 

My clutch makes noise when it's pulled in. The plates make
light contact and bang around some.

I've also had bearing failures.

When a bearing cage fails, that also makes noise and
gets worse, louder and more expensive very quickly. That
kind of failure shows up as metal in the oil. The metal can
be as fine as flour paste or later on, sharp beebee size
chunks. Steel can be pulled out of the oil with a magnet.
Bronze will stay suspended.

If you're worried, do an oil change and see what you
find in the oil. Easy way to reassure yourself that nothing
really bad has already gone wrong. Then just keep
an ear open for new noises or changes in behavior.
If you don't already have a magnetic drain plug, you might
see if there's one available and install it when you change
the oil.

Eventually, you'll be due for new clutch plates anyway
and you can have a better look then.

 

Awesome!!

I'll bet you get tremendous savings on fuel too.

 

When engine parts don't get enough oil, they start wearing out. Once
the wear gets through the hardened outer layers of steel parts, they
start wearing really quick.

But we still don't know whether the noise you described has to do with
the
chain and sprockets, or if you still have the noise when the
motorcycle is not in motion.

An old mechanic's trick is to listen to various areas of the engine by
touching it with the tip of a long screwdriver and then putting your
temple against the plastic handle.

If you don't happen to own a large screwdriver like that, a piece of
hardwood dowel
about a foot long works well.