When I returned home I did some research on the little machine. It was a Unimat DB200. Unimat stands for “UNIversal MAchine Tool”, as it can be configured as a lathe, a milling machine, a drill press, and many other tiny power tools. This one had a heavy base of cast iron, which makes this an earlier model. I already had a much larger Grizzly lathe, but I thought that this little Unimat could be useful for tiny work. I thought it would make for a fun restoration project, too. I watched countless videos about the Unimat to become more familiar with its operation and capabilities.

When I returned to California 6 months later, I asked about the lathe’s history, but my cousin had no recollection of it and told me to take it. I shipped the Unimat back to Michigan on September 12, and it arrived September 18. It had both a 3-jaw scroll chuck and a 4-jaw independent chuck, in addition to a face plate and clamps to hold irregular objects. It had a Jacobs chuck and a live center for the tail stock. The original tool holder still had a high-speed steel cutting tool in it. My goal for the project was to return it to as close to original condition as I could. Many hobbyists seem to replace the original motors with larger, more powerful units, but I wanted to retain the original compact size and appearance. The little 90 watt motor would suffice.

On October 10, I completely disassembled the lathe to assess what I had. There were some damaged and worn pieces, which I found replacements for on eBay. I also made a few replacement pieces on my larger lathe. At some point in this tool’s long history, somebody repainted it in a dull tan-gray primer. The cross-slide was previously molested by a drill, and an ugly block of metal was added to it for reasons unknown. The main spindle bearings and races were in surprisingly great condition, but the pair of small ball bearings for the idler pulley were frozen solid, so replacements were ordered. I don’t plan on doing much, if any, milling with this tiny tool, but I ordered a replacement milling table to replace the original that had a chipped corner. The original belt made from braided rope would certainly be replaced. Both the main and cross slide lead screws were slightly bent, so I ordered replacements for each. Every part was ultrasonically cleaned.

I wanted to repaint it using a hammered green paint that was similar to the original finish, but this color was available only in a brush-on paint. I opted for a hammered copper color spray paint instead. The layers of paint were chemically stripped away, then all painted pieces were masked and primed before the hammered copper paint was applied. I made new aluminum rivets for the faceplate.

Reassembly began on October 26 and finished the following day. The Unimat ran again for the first time in decades. I still need to use my dial indicator to ensure that the cross slide tracks true and that the head stock has minimal run-out, but otherwise, the lathe is back together. The wooden box still needs reconditioning, but that will be a project for another time.

I’m quite happy with the results of this project. For fun, I set the tiny Unimat on my Grizzly lathe for a quick picture to compare the size difference. While the Grizzly will get most of the lathe work, the Unimat will be ready for any future micro-machining needs.

The results are incredible, and my parts look as good as when they were first cast over 50 years ago.  It will be like building an engine from new parts.  Vapor Honing has gained favor in the automotive and motorcycle restoration business, in addition to firearms restoration.  The results speak for themselves.

Typical for Honda engines of the period, there is no external oil filter, but instead a centrifugal oil “slinger” which removes particles from the oil by spinning a finned chamber at high speeds, causing the particles to be thrown to the outside of the chamber instead of circulating through the engine.  There was a heavy accumulation of crud in the chamber when I opened it, which required heavy scraping to remove.  I suspect that this chamber wasn’t cleaned with any regularity, if ever.

I have yet to clean all the head parts, but so far I’m pleased with their condition.  The valves look great, as do the valve seats.  At this point I plan to clean and lightly lap the valves into their seats during reassembly.  The valve guides are also in excellent condition.  After taking measurements with a micrometer, the camshafts are all within spec, and at the high end of the range, too.  I already have a new camshaft chain, so I didn’t bother measuring the original.

I’ve removed the iron cylinder sleeves, and will simply retire them.  I’ve ordered new forged pistons and iron cylinder sleeves, which should arrive by the end of the year.  The engines cases, cylinder block and head still need to be cleaned and either bead blasted or vapor blasted to return them to original appearance, after which I’ll have the cylinders machined and honed to fit the new pistons.

These engine rebuilds are lot of fun.  I’ll post updates as progress is made.

It took about 2 hours to take the engine apart.  Like other Japanese motorcycle engines of the era, there were quite a few Phillips screws used to assemble the engine.  Roughly half of these screws loosened with the hand-held impact screwdriver, but the other half turned to mush and required drilling.  This means I’ll need to extract the remnants of those screws before the engine goes back together.  Although I’m aiming for an authentic restoration with this project, I will not be using Phillips screws when the engine goes back together.  These will be replaced with Allen-socket button head screws.

These engines were known to wear out the kick-start bushings, so I’ll press in new bronze bushings.  The transmission gears were in excellent condition, including the engagement “dogs”, of which none showed any signs of rounding.  I haven’t taken any measurements of the transmission shaft bushings, but I’ll replace anything out of spec.

One small surprise was a hairline crack in the upper engine case.  Oddly, the crack is only visible from the inside of the upper crankcase, not from the outside.  I have a spare upper engine crankcase that I could use as a replacement if necessary.  I had intended on retaining the original upper case to preserve the relationship between the frame serial number and the engine serial number, but I may have to use the spare upper crankcase anyway.  The lower crankcase will not be reused, as the lower right casting was broken away and missing.  The replacement lower crankcase is in good condition and all sections are intact.

The cylinders appear to be in good condition, but I expect to replace the cylinder liners anyway since my plan is to also replace the original cast aluminum pistons with stronger aftermarket forged aluminum pistons.  That will require the cylinders to be machined to fit the new pistons, so it only makes sense to replace the cylinder liners too.

The most difficult parts to get are replacement chains, and inside this engine, there are a bunch.  The centrifugal oil filter is driven by a tiny chain.  The overhead camshaft is chain-driven, and the engine’s primary chain, which connects the crankshaft to the clutch and transmission, is a noted weak point, good for roughly 10,000 miles.  This bike has 19,000 miles on it.  I’ll have to do some research on replacement chains, and take measurements of the existing chains to determine their condition.  The primary chain tensioner wheel is aged and the rubber is cracking, so that can’t be reused.  Same with the camshaft chain tensioner.  I’ll look for aftermarket options and do some research.

During this Winter I’ll continue to work on the engine.  I have some parts to hunt down.  I’d like to be reassembling the Scrambler in the Spring of 2018, so I have to get busy!

The first thing I noticed was how smooth the ride was.  The crude original wheels were anything but round and balanced, so these new rims and tires felt great.  The new leading-link front suspension handled well and tracked nice and true on the road.  The custom wiring design has been good so far, with all-LED lighting and an electronic turn signal flasher.  No blown fuses so far.  The hand-made leather seat was much more comfortable than I expected – a very pleasant surprise.  I could ride in that seat all day.

The test ride did reveal a few minor issues.  The ignition timing needs adjusting, and the clutch cable could use a quick adjustment as well.  The neutral switch is wired correctly but the neutral switch isn’t working reliably, so I’ll need to look into that.  Otherwise, the bike feels good and ready for use.

The rear tubular tail light housings were purchased unpainted, and had to be manually ground to fit the unique curvature of the motorcycle and sidecar fenders.  Once fitted, the housings were painted black to match the fenders.  These round lights have a vintage appearance and look much nicer than the original Dnepr stamped sheet metal mounts and rectangular tail lights.  While appearing vintage, these tail lights will house modern LED bulbs for improved brightness and reduced electrical draw.

The wiring for the turn signals is complete, and the turn signals on the motorcycle itself are working well.  I still have to wire the right turn signals on the sidecar, in addition to the running lights, headlight and brake lights.  I also have a few dummy lights left to wire, such as the neutral light and oil pressure warning light.  A month ago I completed the wiring for the alternator, voltage regulator and discharge dummy lights and all are working perfectly.  The voltage is as 12.5 before starting the engine, and 14.3 when the engine is running.

I have about 3 to 4 hours left to complete the wiring, at which point all the wires will be bound into a harness to keep things tidy and protected.  The rear brake linkages are connected as well as the sidecar brake cable, but I’m not yet satisfied with the adjustment, so I have to look into that too.

I’ll not make much further progress in August due to a packed schedule, but I do have the entire first week in September off work, so that might be the best chance to finish the work and get the bike back on the road.  We’ll see.

Since the Dnepr didn’t originally come with metal toolboxes, there were no existing mounting points on the frame.  After some searching I decided to use brass plated copper Munsen rings, which are designed to suspend pipes from above.  The Munsen rings were available in the diameter I needed, and the brass looked great against the black painted frame.  Since the base metal was copper, the rings should flex as needed under stress and not crack.  Besides, the toolboxes were not heavy.

To mount the electrical components inside the toolboxes, I planned to use 1/4″ plywood.  I could have simply painted the plywood, but in a case of overkill, I naturally chose walnut burl veneer to cover the plywood.  The veneer was inexpensive and readily available, and while nobody would see it unless the toolboxes were open, I thought it would add a classy touch to the project.

I used a contact adhesive to glue the veneers to the plywood.  Once the panels were cut out, I lightly sanded the veneers before spraying a satin polyurethane on all sides to seal the wood and bring out the beauty of the burled grain.  The location of the toolboxes couldn’t have been better, too – right next to the battery box.  Therefore, most wiring will be completely concealed from view – a big improvement over the original Dnepr design.  The left toolbox would contain a new switched fuse panel, electronic turn signal flasher for the LED signals, and the master battery toggle switch that previously hung below the rider’s seat.  The right toolbox would house the voltage regulator, rear brake switch, and another toggle I added that would allow the right turn signals to be switched between the motorcycle and sidecar in the unlikely event I ever opt to ride the motorcycle without the sidecar.

I’m pleased with the appearance and functionality of the toolboxes.  While I won’t be doing any intentional foul weather riding, the electrical components will be shielded from weather and dirt, and there will be no ugly exposed wiring.  I still need to mount the rear fender lights before I begin creating the custom wiring harness.  I should make more progress at the end of May.  Stay tuned.

That said, my neighbor Don decided that I was just the right person to take ownership of his “baby”.  He priced it low, too, after I had initially passed on the offer.  Sure, twist my arm, Don.  Today, the 1966 Honda CL77 Scrambler was rolled into my garage, waiting in line for its turn for a rebuild.

The Honda CL77 Scrambler was a 305 cc twin-cylinder motorcycle made from 1965-1967, although some bikes made in this period were titled with a later model year.  Like most 50+ year old motorcycles, this example has accumulated a fair number of modifications that I’ll need to correct to bring it back to near-original condition.

While the vibrant blue paint is well done and striking, it’s totally wrong for this machine, which came from the factory with a light silver color on the fuel tank, fenders and side covers.  Since the CL77 had at least some light-duty off-road inclinations, I found it rather odd that a previous owner added “highway pegs” to the front, allowing the legs to rest straight forward as with a chopper-style bike.  Likewise, the handlebar is a tall, cruiser-style mini ape-hanger that looks out of place here.  The seat was unprofessionally re-covered at some point and looks like a tall sack of potting soil, so that will go, too.

Some changes I’ll be making will be to improve reliability and durability.  This engine used a twin set of points in the ignition, so I’ve already acquired a nice electronic ignition module to replace it.  Once the ignition timing is set, I’ll never have to touch it again.  Electronic ignitions, with their modern circuitry, require a fairly constant, spike-free voltage level, and this CL77 didn’t come with a voltage regulator.  I’ll install a combination voltage regulator/rectifier that is matched to this model’s alternator.  The original ignition coils will be replaced with high-output coils that will produce 2 to 3 times the voltage at the spark plugs, improving starting and engine performance.

I’ll replace the wheel bearings, but the wheels and spokes are in great condition, and the tires were replaced 2 years ago, so those will stay.  Gaskets and seals will get the usual attention, and because they are cheap, all the cables will be replaced.

Fortunately, I should be able to clean and re-use the exhaust pieces.  That’s good, because as motorcyclists like to say, this exhaust system is made from “unobtanium” and when good pieces do show up online, they get bid into crazy price levels.  While it may be possible to replace the high-rise exhaust with a standard low set of pipes from the CB77, it would obliterate the key feature which defines a Scrambler, so I’ll do everything I can to retain this exhaust.

With travel planned for April and May, and the Dnepr waiting to be completed, I expect to start this CL77 rebuild later in the Summer.  I’ll post the updates here.

I lubricated all 5 cables before routing and connecting them.  Once I get to the point of securing a wiring harness in place, I’ll do my best to hide the cables, or at least mount them so that they are less noticeable.  On the handlebar, I had to make some adjustments to secure the inverted hand levers, but I love the vintage look of these levers.

The rear axle and drive shaft were also installed.  Since many fasteners were only hand-tightened to test each part for proper fit, I removed many fasteners and applied a thread lock compound before re-tightening.

It will probably be a few weeks before I make more progress.  Thanks for checking in.

I then slipped the left exhaust pipe and muffler into place for a few pictures.  I like how the bike is coming along so far, but as the temps slip into the freezing range, I’ll soon be setting up the heater in the garage for future work.