Just when things quieted down, just a bit, a new rescue opportunity presented itself online…
They always look better in the pictures, but this low-mileage Orange CB200T had suffered a catastrophic failure, which I had never seen or heard of before. I found the post, somewhat by accident on OfferUP classifieds, and it was located in Pacific Beach area, about 25 miles from me. The post showed about 8 photos, including the one where the end of the camshaft had broken away from the camshaft body. In person, the bike was suffering from the usual 50-year-old chrome pitting and alloy corrosion, not to mention that it was just pretty dirty from sitting somewhere exposed for a good part of its life.
One can only imagine what would cause such an unusual failure of such a sturdy Honda part. I couldn’t even guess at the cause, unless someone had tried to over-tighten the spark advancer bolt on the end of the camshaft and somehow broke it off in the effort.
The owner, Corey, had purchased the bike for basically market prices for a running, titled and registered 1975 Honda street bike. When I went to have a look and purchase it, he said that he was riding it back from a fresh purchase and somewhere along the return ride, it just went Bang! And that was the end of that. He admitted that he wasn’t much of a mechanic, but tried to figure out some possibilities on his own, including replacing the ignition coil, which was valid as the plug wire was broken at the coil case and attempted a few more things, until he checked the points and found the end of the cam was broken off.
We loaded it up into the Tacoma and off I went on a new, puzzling adventure with a little CB200T, which was the final successor to the line of 160-175 from the mid-1960s to the early 1970s. Honda had reworked the engine with larger wrist pin sizes for the pistons and rods, plus created some rubber intake manifolds to reduce some of the shaking and quaking of a 200cc engine with a 360-degree firing crankshaft design.
I offloaded the bike in the driveway and started peeling parts off of the chassis. I was quite surprised to find that not only did the footpegs have thick rubbers, but the whole footpeg and sidestand assembly was rubber-cushioned where it bolted to the frame. The engine’s OEM carbs were disassembled in a box and a pair of shiny new Chinese copy carbs tucked into their places. The Chinese versions of replacement carbs only goes so far, as they chose to put two right-side carburetors together as a set, instead of replacing the normal left and right oriented carburetor configurations. Using two right side carbs puts the left side carb adjustment screws inboard between the pair, as well as causing the left side fuel hose to exit on the left and then snake around to meet up with the petcock on the right side of the fuel tank.
I proceeded to remove the side covers, air box covers, air filters, which are fitted with the rubber connector tubes to the carburetors, all in one piece. One of the pluses of the bike was that it still had intact OEM mufflers that hadn’t rotted out on the bottom. Soon, it was time to yank the hefty motor out of the frame and put up on my Work-Mate bench to drain the oil and remove the top end for further inspection.
I have a handy 18v power ratchet which helps buzzing off a lot of long bolts and makes the tasks much quicker. The top cover came off easily, as long as you remember the little 10mm bolt in the front edge. Then, I had to puzzle out how to get the camshaft out of the head. One of the apparent changes from the 175 to the 200 engine was that the 200 now had an endless camchain and a bolt-on cam sprocket, instead of the earlier bikes with a master-link type camchain and pressed-on sprocket. The camshaft is bolted to a removable sprocket with 2 bolts, then you have to pull the rocker arms and shafts, giving clearance around the camshaft area. I dismounted the chain from the cam sprocket after removing the two bolts. Then, it was a matter of snaking the camshaft out of the head and camchain. I tried moving the chain to one side of the camshaft mounting ears and then the other, but it seemed like the cam was a bit too long to just tip it out of the head. The end of the camshaft that is part of the tach drive has a thin, hollow knock pin that connects the tach drive end with the camshaft. Removing the knock pin allowed the camshaft to finally be worked loose from the head.
Next, the cylinder head was lifted off and taken to the workbench. Looking at the colors of the carbon on the valve heads looked like it didn’t have a lot of miles on them, backing up the 5300 miles showing on the speedometer’s odometer. Another change to the 200 engine is the use of long-reach D8EA spark plugs vs the older D8HA plugs with about a 1/2” reach. I used a special tool to clean up the spark plug hole threads, as one side looked a little bit like it had been cross-threaded at some point.
The piston crowns were carboned up, and the ring identifying marks were worn off. When I turned the engine over to allow the pistons to go to the bottom of the stroke, I could see recent honing marks on the cylinder walls that were not factory-made. Lifting the cylinders off revealed the green gasket material used on aftermarket D&K gasket kits from Thailand, so obviously someone had been poking around inside the engine in recent times. The repair history was unknown to Corey, but there was a sticker on the tail light lens that had the name of a shop in SD County. One might infer that whoever had the top end apart and back together again might have failed to tighen up the spark advancer bolt sufficiently and with a few miles driven, the whole thing went sideways in a big way.
Some previous owners had replaced the stock CB77-sized tires (2.75x18 front and 3.00x18 rear) with a 3.00 x 18 front and a 3.50 x18 rear set of IRC tires. Not only that, but the rear shocks were all shiny new and apparently just about a 1/2” longer than the OEM shock lengths. This caused the swing arm to be pushed downwards towards the mufflers, basically preventing chain maintenance or wheel removal without dropping the exhaust pipes down. In one of those odd MrHonda synchronous events in my life, someone had dropped a bunch of misc used parts with me a few years ago. The only part that I thought would never be used was a pair of OEM CB200T rear shocks! I found them, disassembled them for cleaning and reassembled them to use as a replacement for the too-long aftermarket shocks on the bike now.
I popped the wrist pin clips out of the pistons so I could clean off the carbon build-up and remove the rings to check for excessive end gaps in the cylinder bores. For some reason, Honda uses two, seemingly identical piston rings for the top two positions. On most all of Honda’s piston rings, the numbers are marked on the top with a T or oversized mark, but the “scraper” ring only has a 2 mark, as I recall, for placement of the ring in the second piston ring land slot. Unlike most other scraper rings, which have a very decided scraper lip on the bottom edge of the ring, the rings for 175-200s have these mystery rings instead.
So, I ordered a bunch of replacement parts for the little bike, including all new cables, a new battery, new spoke kit, a new front rim (rusted badly), engine gasket kit, while still fishing for a good used camshaft to get this bike back on the road again. Honda made the 200T bikes for 4 years, so you would think that parts might be floating around. There is some use of 200T engines parts for the AHRMA racer group, so I might hit them up. Ironically, right after this bike was posted on OfferUp, another horrible ratty parts bike showed up for $250 asking, which might solve the camshaft problem, but then you wind up with a pile of ratty used parts that no one wants.
Thankfully, a member of one of the two CB200T Facebook groups replied to my pleas and actually turned up a nice, used camshaft with the advancer and sprocket still attached for $60 plus shipping.
More problems arose when I dismantled the front mechanical brake caliper to allow for a cable change. There is a little cone-shaped spring that puts pressure on the plastic disc that helps the brake to be self-adjusting. Of course, the spring was not to be found so the only one listed for sale on eBay was in Thailand.
Someone had listed a front brake cable on eBay, but it looked like a conventional adjustable brake cable seen on most drum-braked vintage Hondas. It was listed as fitting a CB125 and CB200T, plus the CL200 models. Obviously, the two different brakes require different cables and the one arrived as the CL200 version. It was only about $12, anyway, but the seller refunded the money and I kept the cable. Finding the correct cable is kind of difficult and I found a seller in Norway who had one for $40 with free shipping! According to the eBay listing, the seller had sold 155 of them already.
There was a big ugly spot of rust on the front rim, so I found a NOS rim at CMSNL and some spoke kits from Thailand. The next search was to find a 2.75x18 front tire so I could change out the whole rim, spokes and tire at the same time, the use that tire to install on the back wheel to get the tire sizes correct once again.
I had the top end components, including the cylinders, cylinder head, end covers, tappet covers and top cover vapor-blasted by my local friend Jon, who has the whole setup in his busy garage. I’ll scrub up the bottom end as much as possible and the rest will go back together with a shiny top end and patina on the bottom.
The rear fender chrome was pitted in the section beneath the seat, so it was removed and cleaned up. The front fork seals were on the list of repairs, so those were purchased. The intricate boots are NLA, apparently but are not torn at the moment. It is easier to rework the front end when no engine is installed.
Fork seals were replaced and the engine started up successfully. I drove it around the block and down a half mile away from the house. It seemed to be running well, but the petcock, an aftermarket version, was leaking internally. I had to drain the tank and disassemble the petcock to find out what was going on. The back side of the fuel lever was somewhat distorted and running a smooth file across the face revealed the high spots and low spots.
It was all going well, until I checked the headlight bulb, which tested fine. That only left the infamous starter button switch, which was a problem for a number of the mid-1970s models. The handlebar switch also carries the brake cable, brake lever and front brake light switch. I bought a switch from Indonesia that was supposed to be the replacement for the OEM switch but the internal switch function was poorly designed and blew the main fuse out when it was tried. Shockenly, the few new OEM handlbar switches were listed at between $250-300 and all were in Asia somewhere.
After consulting the wiring diagram and looking at the Instant ON headlight function, I decided to rewire the starter solenoid so it used the handlebar switch to ground the circuit, instead of toggling the 12v to the starter solenoid. Using a readily available CB175 switch seemed to be the answer. It won’t have the kill switch function, but will have the option of turning the headlights On/Off manually.
(See the accompanying story about the headlight switch fix)
In the middle of all the repairs and parts ordering, I crashed my 91 NT650 Honda Hawk GT650 and broke my thumb, so doing repair work is challenging to say the least now.
June UPDATE:
The bike engine was repaired, the front rim was replaced with a NOS one and a new tire installed.
The aftermarket petcock kept leaking internally, so a NOS OEM Honda petcock was purchased for about $60. The registration ran out at the end of April, so I titled the bike in my name on PNO status.
I was torn as to whether to keep it around for a local parts chaser bike to sell it as my garage was otherwise full of 305 Super Hawks. I put it up for sale.
In the last few weeks, another CB200T showed up as a customer bike, which had been dead for about 10 years. Pulling the carbs apart for cleaning and inspection revealed that the carb slides had been installed backwards, which caused fuel fouling of the spark plugs and stalling at an idle.
The petcock was incorrect with one fitting instead of two for the carburetors. I replaced it with an aftermarket unit that was correct for the bike. There were LOTS of issues with electrical system components, as all the turn signals and the headlight were converted to LED lights. The handlebars were changed to a lower version and all of the switch wiring had been routed outside of the handlebars instead of through the insides. The fork ears were replaced by aftermarket units which had slid down the fork tubes, which had been painted. The paint cause grounding problems for all of the wires inside the headlight shell. The wiring harness was an aftermarket piece, so sorting out the correct wire colors became an issue.
The mechanical front brake caliper was frozen up inside, so the brake was non-functional. It was disassembled for cleaning and lubrication while a new OEM brake cable was ordered and installed in the same process.
The engine was tuned up with camchain adjustment, valve clearances checked, carbs cleaned and ignition timing reset. The spark advancer was removed and cleaned/lubricated, as well.
With aftermarket handlebars, the cable lengths were a bit off and needed to be routed differently.
The “cafe” look had been accomplished by cutting up an original fuel tank and creating a bump-stop seat! The stock tank had been sealed, but the gas cap was coated with the tank sealer, so a new fuel cap was ordered and replaced. Ultimately, it all came together and was picked up after being in the shop for a couple of weeks. My broken thumb is getting stronger and I can do a lot of mechanical work again, but the hand is still a little weak and sometimes painful.
Anyway, as so often happens to me, not one but TWO unusual bikes showed up during the same month, and they are now back on their wheels and in circulation once again.
Bill Silver aka MrHonda
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