Report: July -
* Greased all fittings.
* Oil Change to 10W40
Upon cleaning the Oil Filter, I
discovered that the O-ring which fits into the oil filter (part #91304-259-010 [48.6 x
16m] - as described on the Honda parts bin label) was broken again.
This was a brand new, Honda supplied O-Ring 1,249 miles ago. So was the previous broken
one I changed 1000 miles before that. I then thought that the summer heat had
o-ring brittle enough for it to break up in the 1000 miles of service. But when the second one
broke in the same place, in about the same number of cooler weather miles, I had to
reexamine the situation closely.
Both o-ring breaks ended up severing the o-ring in two places which gave me two chunks of
the o-ring - a 1.5" piece and the remainder. I have to say that the rubber did not
appear to be brittle as I thought it was two oil changes ago. The surfaces of the oil
filter and the oil filter cap - the two shoulders that comprise the groove in which the
o-ring sits when everything is assembled - are completely smooth. Yet the two breaks seem
to be somehow related to the position of the oil filter's inner fins.
The only thing I can think of is that the oil filter cap (perhaps even the body) may be
slightly out of balance. Could this create the type of a vibration that puts a stress into
two spots along the o-ring seat?
The question was posted to the
VJMC mailing list and one of the responses recommended using white lithium grease to
lubricate the oil filter cap along with the inner walls of the filter body and also to
"glue" the o-ring to the cap before reassembly. That way the o-ring has a better
chance of not slipping off at reassembly. If it does slip off, it might end up being
sliced by the cap as the spring clip is being reinstalled.
* Disassembled the oil filter
assembly to reexamine the new o-ring. I should note that the motor had not been started
yet by this point.
* The o-ring was positioned
* Applied high temp. grease to
the cap and the filter walls; "glued" the o-ring in place; reassembled.
* Disassembled the oil filter
again, before starting the motor, just to be sure everything is fine. The o-ring sat snug
in its groove.
I will have to revisit this topic at the next oil change. For
now one thing is certain - the o-ring fits its groove perfectly and does not slip off
during reassembly. This is certainly true now that I am using grease to hold it in place
while slipping the oil filter cap into its place. The only thing that can lead to it
breaking up in a short number of miles is excessive vibration of the oil filter housing...
Final Prep for the Long trip:
* Oiled or greased all cables.
* Adjusted the throttle cable to
return the proper 1/8" slack at the handle twist. [Later this proved decisive
in almost complete elimination of the high rev sticking condition - a persistent problem
on my bike for a long time.]
a) the shift pedal linkage &
b) front brake shoe linkage & cable
c) rear brake shoe linkage & cable
* Carb bowls off, jet holders
off; synchronized the carbs.
* Topped off the battery;
* New spark plugs NGK D8HA.
* Reset point dwell and timing.
* Adjusted and lubed the drive
* Oil change to Valvoline 20W50
[this brand of semi-synthetic 20/50 oil is excellent on the highway and in warm weather,
but makes for difficult starting in cool weather. Generic organic 20/50 oils are the
next step for the ensuing fall...]
Gave the bike the final once-over and took off on a 1000-mile trip.
The bike ran excellent; it seems
that long and hard highway runs - between 6K and 7K RPM and long sustained (hours on end)
speeds of 60 to 80 MPH are to the bike's liking. Although I make no claim to the
universality of this on other SuperHawks, but during these endurance runs, I noticed no
degradation in engine performance and perhaps even an improvement as some carbonation was
purged from a well tuned motor. This is without a doubt a testament both to the
racing heritage of these motors and to period Honda workmanship. Think about it,
this is a 305 cc motor manufactured 34 year ago!! Also encouraging is that the new
clutch springs seem to have greatly improved hot shifting with hard shifting largely
Most of riding was done in two
500-mile days, taking me from Boston, USA to northwest of Montreal, Canada. At the
end of the first day (having already arrived to the final destination) the clutch cable
broke; the barrel end which fits into the clutch lever separated from the cable - probably
due to the combination of (a) age of the cable and (b) new clutch springs. The
temporary repair was to use cable adjustment hardware to extract all available slack and
then to feed the cable end through the clutch lever and then through a tiny nut.
Then the cable/nut end was clamped with small Vise-Grips which were, in turn, secured with
a long tie wrap around the handle bars (lest they vibrate open en-route). After
this came together, the clutch cable was readjusted and clutch operation restored.
Say what you will, but this fix worked and I made the return trip of 500+ miles without
further clutch incident.
Time for another Road Trip:
Big agenda; I need to address the
hard shifting on long rides & when bike is very hot. New clutch springs have
come in and that will give me a chance to examine the clutch disks, plates and other
Clutch disks: two of the clutch
disks are from a CB72 - smaller contact patches - they happen to be the ones behind the
wire retainer rings, i.e. deepest in. They are obviously left overs from the
previous clutch work where the PO was too lazy to undo the wire retainers. They are
thinner and are breaking down; with visible pitting. The other four disks appear to
be in great shape; they are much newer with lots of meat on them. I wonder if there
is anything wrong with replacing only the two worn out disks..? I changed the order
of reassembly of disks and plates to give the set new mating surfaces; will monitor
Plates: some plates show evidence of high spots where the grab pockmarks have been
obliterated along an edge, but no more than 15% (at most) on a
given plate. One or two plates show mild blueing from some overheated moments.
The aluminum cap has some mild wear groves along the disk contact path.
Springs: this is mainly what I set out to do (I decided not to dig deeper to the
primary chain, etc., for the time being). The old springs have thinner coils than
the 22401-272-810 replacement springs. The new
springs are shorter by about 3 or 4mm. I am concerned with that the new springs are
cut rather carelessly - at an angle. If the old springs are set on end on a bench,
they more or less stand straight, but the bases of the new springs are machined such that
each has the tower of Pisa lean, to various degrees.
Oil filter: I was surprised to find that there is a noticeable deposit of aluminized
sludge in the filter - after only 1000 miles (600 of those, highway). I was able to
wipe the sludge off with a rag and some
carb cleaner, but I was really really surprised that the oil filter O-ring had brittled up
and broke when the oil filter cover came off. That O-ring had been just fine at the
last oil filter cleaning 1K miles ago. This $3.00 Honda O-ring (the local bearing
house did not have the correct size) was installed only about 3,500 mile ago. Good
thing I had a spare.
Gasket: I was very happy to discover that the gasket I installed 3,500 miles ago was
perfect and came off without leaving even a thread of itself on the engine case.
It's all in the prep, I guess... The last time I installed this gasket, all mating
surfaces were cleaned well and the gasket was coated with high temp grease on both
sides. No oil leaks from the case cover either and I was able to reuse this rather
* Replaced the spark plug wires
with a new 8mm wire; cut to length and sealed with silicon paste.
* Installed new spark plug wire
* Cleaned the petcock bowl - lots
of debris & sediment!
Continued road trip preparation:
* Side Bags all wired up; they look Great! Even better when lit up...
* Installed new spark plugs.
* Set the timing.
* Adjusted the valves (excessive
lateral play remains on rt. exhaust rocker shaft - noisy when off load at 3-5K RPM).
* Topped off the battery.
* Greased all available
* Gave the bike the final
PS When taken on a long trip,
just days after this log entry was made, the bike made an unplanned for 19-hour, 580-mile
day run without a single problem!
Continued road trip preparation:
Removed the backup carbs from the
cleaner, stripped some parts (jet & holders, one of the floats, needle & seat) and
retrieved the desired right side titanium slide.
* Removed the rt. old, chromed
carb slide. Removed the needle and mounted it into the titanium slide.
Checked the needle height (with
the high speed jet holder removed) and adjusted the needles to protrude by the same
length. The only adjustment that can be used here is the idle speed screw.
Once both needle tips protruded by the same amount, I discovered, to my horror, that the
right side slide was significantly higher (in the carb throat) than the left one.
This could mean only one thing - that the needle clip was set incorrectly on one of the
Both were removed and, sure
enough, the left slide needle was on the third step, whereas the right one was on the
second (as is correct for CB77 bikes). This is a great discovery as I am positive
that no matter how well synchronized the carbs had previously been, they could never have
reached the optimum setting, for obvious reasons. Just to think that I had ridden
over 3K miles that way!
* Reinstalled the slides
* Returned the throttle cable
adjuster to their default settings and resynchronized the carbs.
A side note here on CB77 carb
synchronization. The only way to really get it right is to have the carb bowls off
and the floats and the high speed jet holders out. Only then can the lower tips of
the needles be seen and a truly synchronized action achieved in adjustment.
Additionally, as seen from above, more otherwise invisible carb setting problems may come
* Drained the right side front
* Refilled with 250cc of ATF
Front shock action seems to feel
good. I can't wait to go riding!!!
Began work on wiring up the four tail lights on the side bags. For now, one
lamp (per bag) will turn on with the H/L & T/L and the other will function as a brake
light. Should look excellent from the back. Later, if I find a way to adapt
dual filament bulbs into those small tail lamps, I'll rewire the system to include the
Turn Signal function.
* Spliced in (solder connections,
of course) a quick disconnect plug leadoff from the T/L wiring harness.
* Began to modify/install proper
wiring into the side bags.
Continued with the major tune-up:
* Cleaned and lubed the chain
* Drained the left fork tube;
some sludge came out along with evidence of water. How did that happen? I
wonder... The bike has not been ridden in the rain and has been mostly garaged and
always covered. Besides, how would water make its way in? Perhaps this is a
remnant of some older condensation - after all, the left fork tube did give cause for
concern earlier (see 05.17.98).
* Ran some ATF fluid
through for further flushing and refilled with 250cc of ATF.
* Tightened the shift lever
output shaft to linkage collar.
Attention now turned to carbs:
* Removed bowls - some minor
particles of rust dust - cause for concern; the tank will have to be treated...
* Checked the floats - not sunk
and the needles - light wear, but OK.
* Removed the high-speed jet
holders. Discovered that the right side needle protrudes further than the left by
1.5mm. Removed slides to make sure the difference is not due to differing idle speed
Then I saw that I forgot that
earlier, I had changed the sticking left side slide with a newer version - titanium slide
out of a newer carb. The bench comparison confirms - the final needle height differs
between the old and new slides. Time to upgrade the right side to titanium.
[Some backup carbs with titanium slides went into the carb cleaner just now; when done
soaking, I'll have the desired right side titanium slide].
Not knowing whether the titanium
slide will be available before my trip, I decided to do what I can to alleviate the
sticking old style slide in the right carb.
* Removed, inspected cleaned and
reinstalled the right side slide. Lubricated with liquid wrench.
* Installed a heavier return
spring (from a backup carb).
The results are very encouraging
- both slides snap back when the throttle is released. Encouraging, but a roadtest
will show and both carbs with titanium slides will be better that one.
* Took some slack from the clutch
cable and from the ft. brake cable.
Disconnected the 'winker'
flasher. Discovered some corrosion on the contacts.
* Cleaned the points; dressed with emery
and flushed with contact cleaner. Lubricated the point cam wick.
* Set the right side points to
.012. Will need a timing light to finish the other side and the timing.
* Removed and cleaned the spark
plugs. Had to remove some carbon deposits and flush with contact cleaner.
* Readjusted the cam chain
tensioner. The rubber wheel has begun its deterioration, but still spins.
* Removed the centrifugal oil
filter. Found inside some carbon specks - smaller than sand, but large enough to
feel between the thumb and finger. These seemed to be organic in nature - either
parts of a deteriorated/ing gasket or one of the chain rollers. Will monitor...
Also some sludge, but a very small amount. Someone mentioned that a synthetic
oil has very strong detergent qualities; perhaps this is the effect...
* Removed the oil pump;
disassembled. Measured the clearances between the gears and the pump body - OK - and
between the gears themselves - seems to be above the upper wear limit. New gears and
gasket placed on order. The pump strainer screen had one large particle of the stuff
that - when broken down further - showed up in the oil filter, but otherwise the oil pump
was very clean.
* Changed the oil to Castrol
20W50 and 10W40 (the only oil on hand); will have to get more 20W50 semi-synthetic soon.
The negative battery cable had a
lot of corrosion and a crack at the terminal. I've been meaning to change it for
some time; the '63 bike has a good one.
* Finally changed the negative
battery cable. Not easy to break the bottom bolt loose (engine to frame), but it is
now done - the last known weak link in the charging system.
* Locktite on the rear fender
bolts and some other suspect hardware...
I am preparing the bike for a long trip,
away from home. Not very very long - less than 300 miles, but I'd like to make sure
the bike is in top shape for the trip. Hence the Superhawk is off the road for a
major tune-up and adjustment project.
* Changed rear shocks. The
old shocks were losing their dampening action a bit too much and so, since the 1963 part
donor bike is also red, the shock swap occurred. The '63 shocks feel better and the
dampening action has returned. Will have to see whether the '63 shocks will last as
the test ride was rather short.
* Finally used the opportunity of
the removed rear wheel (hard time removing the spindle - rust & corrosion; white
lithium grease on reassembly) to change the rear tire to the Michelin M38S that I acquired
earlier. Both tires are now M38S; new CH inner tubes.
* Changed the rear brake cable to
a NOS unit I purchased some time ago. I was hoping to revive the rear brake
operation (it was significantly less than desired), or the practical lack thereof which I
attributed to a stretched cable. The new cable improved the situation only
marginally; the culprits are the rear brake shoes - only 1/8" of meat on them.
The new cable is at the very end of its adjustment with still inadequate braking
power. Need new brake shoes...
A short test run reminds me how
much out of tune the bike has become; sluggish throttle response, low power, horrible lack
of rev-down - sticking carb slide - loose chain and poor front shock damping - the
quantity of oil used at the last change (200cc) was, apparently, insufficient.
Oil Change to Valvoline semi-synthetic
news - Installed side bags! The CP77 is
now a Tourer!!! Manufactured by Bates, these babies were sold specifically for any
of the late sixties & early seventies street Hondas. In fact, the installation
sheet that came with the bags lists CB360, CB450 and the CB750 by name; up to the K2.
In order to install the bags, I
had to remove the original luggage
rack w/the rear T/S assemblies, but the side bags have two Tail Lamps each; I'll wire
them up on another occasion...
The bags have their own mounting
frame and rails; the front of the rail fits onto the rear shock stud, while the rear rails
can be adjusted to mount in various locations. The best (only?) place to mount the
rear bracket on a CB77 is to the tip of the rear fender, utilizing the flipper mounting
holes and 6mm machine nuts, bolts and washers.
* Removed the flipper.
* Fabricated an inner fender bracket
out of 1" wide stock steel.
* Fabricated aluminum spacers (in
order to provide proper alignment) by cutting up small ferrules; hacksaw, then grinder.
The results are
quite good; the bags sit well and while not fully rigid, are not flimsy. The added
functionality is very welcome. My lifestyle is changing and is steadily progressing
toward almost exclusive use of the Superhawk as daily transportation; business and
pleasure. Being able to take along whatever without bungee cords is a great
improvement on this arrangement.
* Tightened/Readjusted the
steering head bearing nut. Took out only about 1/4 of a turn, but there is
noticeable improvement in the steering precision. However, the front shocks are
still in need of attention - clunking noise on the rebound.
* One of the rear shock top stud
nuts had a stripped thread; replaced with a spare from the '63 parts bike.
* One of the rear fender inner
mounting bolts (the bolt directly behind the shock stud) was missing; the other side was
loose. Replaced the missing bolt and tightened the other one - fender feels nice and
* Readjusted the H/L. I
must say, for a 25 Watt lamp, the illumination is surprisingly good!
* Readjusted the front brake
cable; removed some slack - about ¼ of an adjuster turn.
* Changed the Oil; 10W30
Left mirror mount - stripped
thread; mirror & the Turn Signal stalk were flapping around in the wind on a night
* Removed the clutch lever, the
horn button & H/L switch and the rubber grip (had to use a 2 lb. rubber mallet to get
the grip off).
* Took the mirror mounting base
(part of the clutch lever assly.) to the machine shop for a Heli-Coil insert. $15
later the part is saved.
* Reassembled all parts and secured
I noticed that the ignition
switch spanner ring started to work loose every so often.
* Locktite on the ignition switch
The bike runs fantastic except
The rear shocks have deteriorated
to the point where they provide little if any dampening.
The right exhaust rocker makes
excessive noise at most engine speeds, especially when not under load. Most
likely, the bike needs a new rocker arm shaft and a rocker, but if one went, how far
behind are the others? In any event, the motor would have to come out - winter
The front end seems less tight
than I would like it to be. Possible candidates for readjustment - the steering head
bearings and replacement of the shock oil.