[ 1997: October -
||First days of
working with my new acquisition:
A thorough inspection is first. Then upon discovery of several
electrical connections of questionable durability I take out the soldering gun and some
heat-shrink tubing. Several of the quick- disconnect bullets are unsoldered, the
wires trimmed, and then resoldered. Lots of bolt-on connections are undone,
terminals sanded, sprayed with contact cleaner, then reassembled. Where appropriate,
the terminal connections are covered with electrical varnish or with dielectric paste - to
seal out moisture.
quickly discovered that almost every rubber terminal cap (rubber hood) and other wire
sealing rubber components has either disintegrated with age or were about to. The
same goes for grommets, but while grommets of most sizes are easy to find, the same cannot
be said about the terminal end caps. Posted this concern to the VJMC mailing list
and one of the respondents suggested checking with a lawnmower shop for such items.
Meanwhile, the battery is
receiving a trickle charge...
||Continuing work on the
electrical connections. Took the fuel tank off for access to coils and wire
looms. Checked the production label on the harness under the fuel tank and the bike
is a 1964, indeed.
the selenium rectifier for inspection and cleaning. Found some flaking paint on the
lower sides of the cells. Cleaned and reapplied electrical varnish to seal the unit
again. I noticed that this is an aftermarket unit, same in size found on the 1963
parts Superhawk, but smaller than what originally came in the CP-77. More research
is needed on this, but for now, contact cleaned and sealed, the unit goes back into its
carburetors are off for a
cleaning. They are not terribly dirty, (after all the bike was ridden to my house
just four months ago) but the right side carburetor float is sunk. Upon removal from
the carb, the float feels heavy and old fuel is noticeably sloshing around inside one of
the float chambers. There is evidence of moderate etching of the brass sides and
some pitting, obviously causing some pinholes. How the bike made it to my house is a
mystery, unless the float sunk within the last several months... In any event, there
is more than meets the eye about the carburetors in the CP77.
First, there are two different era
carburetors; the right side is the old, round bowl, type. This is likely the one
with which the bike had left the factory. The carb shows a moderate to heavy amount
of wear and tear, the most significant being (aside from the sunk float) a slide that
tends to bind in the top area of its travel - at full throttle.
carburetor is the later,
square bowl type. It looks newer and is somewhat lighter in color.
Internally, there are more significant differences; the slide is made from a different
metal than the one in Type I. It appears to be made from a light alloy or from
titanium? as it is noticeably lighter than the older, chrome plated brass slide.
There is a difference in the numbering, stamped into the top face of the slide; the left
(Type II) has "125" and "2.0", while the right (Type I) has
"PW26R" and "2.0". Another important difference is in the design
of the inlet needle; on the Type I the needle tail (which comes into contact with the
float tab) is spring loaded within the needle itself, while on the Type II carb the needle
is a monolith. This comes into importance at the time of setting the float (see the
entry for 10.08.97). I also noticed that the length of the slide return spring is
longer than the one in the Type I carb. In addition, the design of the float buoys
are different - round sided in Type I, flat in Type II.
||After spraying down the
carburetors with spray-can carb cleaner, I drove over to a nearby gas station and asked
whether I could make use of the air hose. They said "yes" and gave me the
blower attachment. After blowing the carbs out, I went home and realized that
I was not sure about how to set the float level; I knew the principle and had done it many
times before on other carburetors, but I didn't know the points at which the measurements are to be taken on
the CB-77 Kei Hins.
question posted to the VJMC mailing list and everything is clarified. A
diagram is worth a thousand words...
||Having decided to limit the
riding, due to the newly formed (newly discovered?) flat spot on the front rim, I decided that some long-term
projects need to be attended to. First, I'd like to solve the high idle problem
which means that the different carburetors need to be replaced with identical units.
I suspect that one of the slides is either sticking or creeps up on its own from engine
vibrations. I had also noticed that the length of the slide return spring had been
different among the two carbs; shorter on the older one. In either event, aside from
being different (early, round-bowl and late, square-bowl) the carbs that are in the bike
now had only been cleaned with compressed air and not soaked.
The part donor - 1963
Superhawk - has
contributed its matched set of carbs for a full rebuild. I am hopeful of good
results as the 1963 carburetors appear unmolested and the slides were not stuck.
Upon disassembly, the first
carburetor - the right side - appears to have had very little fuel when the bike was
parked. The inside of this carb is very close to pristine. However a very
interesting discovery - the slow jet is damaged. The throat tube has two fractures
in the section below the threads. This is obviously a defective item since there are
no stresses on this part whatsoever. I wonder if the same condition might exist in
one of the carbs on my bikes and whether such damage might contribute to a high idle.
The second carb - the left side -
had more fuel in it. Lots of yellowish powdery residue on the bottom of the lower
bowl; some on the upper carb body as well. Some corrosion is preset on the brass
parts, especially on the jet faces. To top thing off, the float is sunk (fuel still
sloshing around inside), making for a 50% float failure rate, based upon the sample of
Disassembly completed, the carbs
go into the carburetor cleaner for a thorough soaking.
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