QuestionHi Bill –
I have a longstanding and annoying clutch issue with my '75 CB360 that I just
cannot figure out. I've posted this to other forums, and have gotten some
good suggestions, but they're all pretty much stuff I've tried already so
thought I'd run it by you.
Other than this clutch issue, the bike is in great shape: 10.5k orig miles (3k
from me over the last year!). The issue is this: At times, when i depress the
clutch lever, if I depress it too far there is an audible "pop" -- sounds metallic
-- from inside the clutch housing on left side of bike (where the clutch cable
goes in, not on the other side). After this pop, the clutch sticks in the
engaged position. If I spend some time fiddling with it, I can adjust the clutch
adjustment screw (the one with the nut on the clutch cover) so that the
popping doesn't happen often, and if it does, i can "de-pop" it by manually
pushing the clutch lever back out (in which case the clutch suddenly pops
back into its standard disengaged position). Unfortunately, the position that
works the best leaves a considerable amount of slack in the cable, so the
clutch is flabby -- you have to pull it a bit before it starts to engage. Here's
some addt'l detail:
1. I have verified that all parts inside the clutch cover are intact and are
assembled as per the service manual (I have Clymer and the Honda shop
manual). I'm not missing the ball bearing, or any other parts (have verified
with schematic). I'm 100% sure that the parts inside the clutch cover are
assembled correctly -- I've replaced the clutch cable 3 times and have
disassembled the cover housing at least 10 times trying to find this problem
(and so has a mechanic I hired). And I follow the shop manual instructions to
install and adjust the clutch to the letter (screw adjustment in until you feel
resistance, then back off a 1/4 turn, lock down nut, and fine tune using adj
nuts on cable and at lever).
2. When I first rebuilt the bike 18 mos ago (had been stored for years), the
clutch was "stuck" at the get go - the clutch wheels and plates had congealed
together, so i had to open the right crankcase cover and manually pry apart
the plates with a screwdriver. This got the clutch working, but the "popping"
issue happened right from the get-go. I haven't had the right crankcase open
since then, but my guess is that the popping must be resulting from
something in the right side. That being said, the pop itself definitely comes
from the left side. My best guess is that the clutch lever (the thing that gets
pulled up when you pull in the clutch lever) somehow over-rotates. Of
course, it’s tough to test this because you can’t pull the clutch unless it’s all
assembled and the cover is firmly screwed on.
3. I have a parts bike, and have pulled all the left side clutch parts off that
bike and tried them on my working bike. No luck, regardless of which parts i
use. And none of the parts have obvious signs of wear.
4. A mechanic i hired thought he had figured it out. What he did is remove
the nuts that adjust the tension of the clutch cable -- the ones at the end of
the clutch cable right as it goes into the clutch cover on the left side of the
bike. Confused why this should be necessary, as the cable is a motion pro
OEM replacement (and I've had 3 to date, since they keep breaking at the lever
-- an unrelated problem due to a sharp edge that I've since filed). I've tried
the minus 3" cable (for my non stock handlebars) as well as the standard, and
neither seems to make much difference.
5. The clutch is quite stiff. Don't have anything to compare it to except my
friend's '76 CB550, but the 550 clutch is smoother and easier to pull. Not sure
if this is a problem or not, but thought I'd mention.
One thing to add. Was riding the bike home tonight on a warmish NYC night
and it reminded me of a few things. First, the clutch pop/stick routine
happens mostly between first and 2nd gear. When i'm in neutral, i can pull
the clutch lever all the way in an hold it and it won't pop. Same is generally
true when in gear and not moving. But it does catch if depressed too far
between 1st and 2nd while moving, and sometimes, 2nd and 3rd.
Rarely/never noticed it to happen in other gears. Second, it seems to
increase in frequency when the engine is really hot. When it's cold, the
popping thing rarely happens. The hotter it gets, the more i notice it.
OK, sorry to be so longwinded but don't want to waste your time (or mine)
since I've been down many paths on this. Any insight would be very
welcome!! Thanks so much.
AnswerSean, Looking at http://www.bikebandit.com/houseofmotorcycles/honda-motorcycle-cb360t-1975/o/m922...
Left crankcase cover illustrations and clutch to review the parts involved.
My questions/comments for you are:
Did you thoroughly clean the clutch plates, including sanding or replacing the steel plates? Rough or uneven steel plates will cause clutch drag, which aggravates your situation.
Do you have a 5/16" Steel ball where it belongs? NOT a 3/8 or 1/4" one instead?
Is the end of the pushrod in the right direction? The flat end goes towards the steel ball. Is the flat end dished out?
Is the pushrod bent or bowed?
Are the ball ramps on the clutch,lever (#4) part deformed, so that the balls continue to jump past the end of the depressions? Replace the lever arm if damaged.
Is there excessive wear on the clutch hub splines or clutch outer slots, catching the ends of the friction plate ears, as it slides back and forth?
Are the clutch springs original parts or H-D replacements? Stock OEM parts should be fine.
The popping sound is the clutch lifter arm assy snapping out of the ball ramps.. or balls jumping out of the lifter arm, if you prefer.
What is critical is that all the conditions mentioned above be inspected and parts replaced where needed. Beyond that, you need to verify that the lifter arm is traveling through an arc ) <-like this.
When the clutch play is all adjusted out, so that you have minimal lever travel, then you must verify that the clutch arm starts BELOW a 90 degree level, travels through the 90 degree point and finishes above the horizontal plane. If you mis-adjust the clutch and cable play, the arm will start above the horizontal plane, causing a loss of leverage through the arc of travel. Always loosen all the clutch cable adjusters up first, then adjust the clutch play for the pushrod, ensure that the cable arm is below horizontal and make sure that the return spring is there and working properly, then take up initial slack at the lower cable adjuster and finish at the handlebar adjusters.
Bill Silver
