After wrapping up the engine work using some new copper sealing washers and nuts for the cylinder head, the starter motor and accessories were attached for final assembly. I eased the 110 lb motor down to an awaiting bike stand which I use for loading engines in and out of 250-305 chassis. Dream engines go up and in with a vertical lift, a little at a time. Some powdercoating was ground away inside the engine mount points to ensure a good engine to chassis ground before engine loading. Dream engine installations are a bit of a puzzle which needs to be done in pretty specific steps otherwise, you wind up having to unhook something to put in a part, once in awhile. The bottom motor mount bolts have to be inserted through the holes in the footpeg mount bracket before they are tightened up. The smaller 8mm bolts must also be in place at the top of the footpeg bracket ends. With two bolts at the top cover and four at the back, the engine is pretty solidly mounted to the frame. The engine harmonics tend to send vibrations back to the end of the rear fender, often resulting in vibration cracks in and around the tail light bracket.
It is best to mount up the air filter/tube in the frame hole
opening before engine installation, however wrestling the carb end of the air
filter tube onto the carb inlet can be a bit of a chore. I had secured all the
proper sized o-rings for the insulator and carb flange so the carb was about
ready to be mounted up when problems arose. The carb had been apart in a
plastic container for a few weeks and they hadn’t had close inspection until
assembly time. While the carb body was undamaged, a previous attempt to remove
the stuck slide caused damage to the front and rear edges of the slide and
mangled the aluminum slide needle to a certain degree. Searching for a new or good used slide and
needle online came up empty-handed. Apparently there are some subtle changes
between the 250 and 305cc applications as both the needle and slide for the
305s have 266 code part numbers, vs. the 259 coded parts for the 250cc edition.
Considering that they both share the same carburetor body and slide bore size,
one wonders just what Honda found to make them create different parts for each
application
.
Digging through the dwindling box of carb parts, a 22mm
slide appeared, but it had a 3.0mm cutaway, vs. the 2.0 cutaway for the Dream
slide. Typically a 3.0mm slide is for the CB/CL72s. Still, it was better than
the poor original slide, so it was put into play, along with a straightened out
needle for temporary running purposes. Doing some research, the needles for the
250 Dreams had a part number revision from 259 to 268, which are for the
CB/CL72 models. I found some cheap OEM 259 needles in Thailand from an eBay
seller, so one will be arriving in the next couple of weeks.
The bike came with its original stainless steel mufflers,
although they were the early style with the sharp-edged openings which require
the black sleeve gaskets. I only had one of the gaskets and no one had just one
for less than $45 (ouch!) so I got a pair from my Thailand supplier on a deal
for $55 including shipping. The header pipes had been rechromed back in the
year 2000, according to the paper that they were wrapped up in. Dream pipes are
side-specific and one side is longer than the other side. I had always been
under the impression that the left side pipes were the long ones, but in the
process of fitting up the headers and mufflers, the long side pipe would only
work on the right side of the bike! Lesson learned/relearned, I guess.
Once all the wires were hooked up, carburetor installed and exhaust
system in place, it was time to light this thing off and see what I wind up
with after weeks of work and quite a lot of expense. The ignition switch was
turned to ON and the neutral light immediately glowed on the headlight shell.
Tapping the starter button for just a second confirmed that the electric
starter was still functioning, as well.
So, with a temporary fuel supply bottle hooked up to the carburetor
line, the choke was pulled fully closed and the starter button depressed in
earnest. The engine spun over about 5
turns, then the starter motor began to labor due to dwindling battery current.
I lowered the bike down to ground level, still on the repair
stand and swung a leg over the chassis to kickstart the engine while there was
still some juice for the ignition coil. It only took a couple of strong kicks
to get the engine to begin sputtering back to life for the first time in many
years. The big carb slide cutaway caused
it to run lean off-idle, so a combination of turning the mixture screw almost
all the way in and raising the idle speed using the speed screw finally kept it
going with the throttle released.
The first few minutes of a new engine startup are critical,
so everything needs to be spot-on for a successful run-up period. After warming
the engine up for a few minutes, it was shut down to check for leaks and to
recheck the ignition timing. The ignition timing was advanced by a good 5-10
degrees, which was reset by rotating the backing plate in the mounting plate
and then reducing the point gap a few thousandths of an inch. The engine sounded good, with no abnormal
noises whatsoever. A quick look beneath the engine revealed an alarming amount
of motor oil dripping off the bottom of the engine. Despite a careful
disassembly, cleaning and use of all new gaskets for the oil pump, there were
signs of leakage in the middle of the gasket/oil screen flange/gasket sandwich.
I really haven’t had these kinds of problems before with oil pump
installations, so it came as quite a surprise to see.
I really wanted to drain the oil anyway and check the filter
for debris that was washed out of the various passages and any leftover media
from the vapor blasting process. The clutch lever was a VERY HARD pull for some
reason. Thinking back, I vaguely suspected that the clutch springs were
somewhat heavier than normal for a Dream engine. That, plus the clutch cable
being used was about 4” longer than the original combined to cause a lot of
friction through the clutch release parts. I had already installed a new clutch
thread in the kickstarter case and the clutch lifter seemed to be in good
shape. Early Dreams use a clutch cable that is over 4 feet long, plus it is
routed through the frame where it makes several tight turns and twists before
entering the kickstarter cover at a 45 degree angle at the rear. Later models used a much shorter cable which
goes straight down the top of the kickstarter cover and that improves the whole
clutch feel/pull effort a lot.
Pulling the left side muffler, shift lever and footpeg off
gives enough room to pull the clutch cover off the engine easily. This early
clutch cover has the “small hole” opening for the oil filter, which prevents
simple filter cleaning as there is no way to open the filter with it still in
place. Later bikes have a “large hole” opening which allows the removal of the
filter through the hole and enough room to hook the filter chain back on the
filter body for re-installation.
With the clutch cover removed, the clutch springs were
removed and found to be probable CB72 parts. The correct Dream clutch springs
have been superseded to 425 code parts from the DOHC CB750. I happened to have
a set of new ones on hand, so that problem was easily corrected. The filter was
disassembled and cleaned with minimal amounts of debris found inside. With
clutch service work done, the cover was reinstalled after the filter was
mounted and the rest of the chassis parts re-attached for another engine run.
The oil pump was removed and checked for obvious sealing issues which were not
readily apparent. The pump was re-installed and new oil added.
The engine started happily with fresh oil in the crankcase,
but the oil pump leak was worse than before! The engine was run for another 10
minutes on the stand, then shut down to cool.
A correct clutch cable came in the mail on the following day, so the
right side of the engine was stripped off to install the new cable, add the
lower chain guard half and recheck everything on that side of the engine. The
oil was drained again and the pump inspected. An additional bottom gasket was
placed on the pump body in holes that it might help smother some of the
invisible irregularities which were causing problems previously.
One week later…
Time out on the Dream project, while I drove to Las Vegas and
back for the Mecum auctions. I hadn’t planned on buying anything and was hoping
that the 1974 BMW R90S project bike would find a home while I was visiting, but
no such luck, so far. I did buy a 1980 Suzuki GN400X which had 3300 original
miles on it for $500, plus fees. After that; out of nowhere came a CR93 Replica
bike that looked eerily familiar. The bike was not on the floor when I checked
that morning and wasn’t in the auction program whatsoever, but THERE IT WAS!
The bike had an alloy CR93 style tank and racing seat. It started out as a
CB160, but acquired a CL175 5-speed engine/trans combo. AKRONT rims were laced
up into polished hubs. Rearset pegs were installed on modified CB72 footplate
mounts. The bike had a CB77 speed-tach combo installed in a CB160 headlight
shell and it even had “winkers” installed! The bike was all polished, painted
and chromed to a nice finish and overall workmanship was well above average for
a one-off machine like this. I wound up paying a pretty high price for the
bike, but I couldn’t have built one for that figure.
After the auction was over, I walked back to see just
exactly what I had won and that familiar feeling returned to me… I owned the
bike back in the late 1990s, but not in such nicely-finished condition!
When I returned home, I had a few boxes of parts waiting for
me, including a set of carb covers and an upper chain guard, both of which came
from a friend in Canada. The parts needed freshening up, but were in good
useable condition, once some new paint was applied. The chain guard seemed to
be different than the original lower half and it took quite a bit of fiddling
round, bending things here and there and
generally spending way too much time on a chain guard installation. Eventually,
I won out and the bike now has a fully enclosed drive chain; but not until
after I removed the whole rear wheel unit, in order to see/feel and adjust the
two halves to blend into a single assembly.
The petcock was cleaned and refreshed with all new sealing
parts inside, then the tank was hoisted up onto the chassis for bolting down
into place. The seat is original and has a very crispy cover with a hole in the
center. The foam is all brittle underneath the cover, so either it will get a
patch of super duct tape or I will have to succumb to buying a cover and foam
package for redo. More and more it seems like every step you take in rebuilding
these bikes is a $100 or more step.
I just read all 4 parts of this story. It's fun to read about your adventures working on the "same" bike my wife and I finished rebuilding in 2013 (our '64.) The round bowl carb you sold me is still on the bike as it allows the bike to run perfectly, and the square bowl unit that came on the bike when purchased just doesn't do the trick.
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