Well, I’ll be switched... vintage Honda ignition switches explained.

New Old Stock (NOS) ignition switches become ever rarer, as time goes on. Every so often something will pop up on a search for a Super Hawk or Dream ignition switch that is one of Honda’s many variations of a single part. This story covers the differences between the various ignition switch options on several of the 1960s twins.

125-250-305 Benly/Dream Switches

The Honda 250-305cc Dream/125-150 Benly models have numerous listings for their ignition switch part numbers, as follows; 35100-259-000 is an ignition switch assembly, but w/o the fork lock. Other similar part numbers include: 35100-202-000, 35100-212-000, 35100- and 271-000. For a full ignition switch with the fork lock, the numbers change to 35010-259-000, 35010-202-000, 35010-271-000 and 35010-272-000. The main ignition switch, used on both the 125-250 Benly and the 250-305 Dreams are electrically the same in wiring colors and functions. Benly models use a different type of fork lock than the Dreams, so that is one reason for the shift in part numbers.

Aside from the differences in the fork locks between the two models, there are two variations of the ignition switches, themselves. For the Benly/Dream models, you have the option of either a 5 position switch or a 6 position switch. New owners of these bikes often call me to ask “What are all these switch positions doing?” So, here’s the rundown: (1) Full counterclockwise position is to CRANK the engine over using the electric starter (no ignition). Next position (2) is where you normally insert and withdraw the key- OFF. Up from OFF is (3) the ON (ignition, horn, brake light, starter switch, neutral light functions) position. Next one, going clockwise (4), is HEADLIGHT ON (includes speedometer light and tail light). 

For domestic models, the #5 position turns on the little driving/parking light located inside the headlight reflector (non-sealed beam units). The last one (6) is for PARK, which turns the tail light ON and allows withdrawal of the ignition key.  Obviously, if you switch the bike OFF by turning the ignition switch key to the PARK position, the tail light stays ON until the battery dies. This is quite a common mistake made by new users of these models, so make a mental note of this if you are out hunting your first Benly or Dream.

US-model Benly and Dream bikes usually came with a 5-position ignition switch, as they all had sealed-beam headlights, so there is no room for a little driving light up front. You can substitute a 6-position switch for the 5-position switch here in the US, but for foreign markets, the 5-position switch option isn’t a good match. I do recall running across a very early Benly switch for a C90 or perhaps for a C70-75 which had no wiring for the electric starter function, which was not used in those 1958-59 versions. You probably won’t run across one of those switches very often, these days.

Dreams were not the only bikes with ignition switch options, as the CYP77 and CB450P Police bike editions had an extra ignition switch position for the patrol light function. I recently acquired a CYP77 switch which carried a 35100-282-000 part number. Ones for the CB450P models carry a -285- center code part number. These parts would seldom be found within the US, under most circumstances, although the twenty-five test unit CB450P bikes from 1965 did have limited parts support at AHMC. I owned one of those first 25 models, back in the late 1990s, and was able to order a new seat and luggage rack for the bike directly from US Honda warehouses. The CYP77 ignition switch, recently found, came down from Canada, where they did have a handful of Police models shipped for testing. When I built up my personal CYP77 Police bike, back in 2002, I was able to purchase several rare CYP77 parts from the suppliers in Canada, where the bike actually came from, as well.

Again, you can use the CYP77/CB450P switches in a standard street bike, however, you will wind up with a spare electrical switch position and wire terminal connection, unless you want to wire your phone charger into it. It is interesting that a quick search of eBay listings for Honda Dream/Benly ignition switches popped up some 6-position switches, for sale here in the US, with 202 and 271 code part numbers attached. One wonders if Honda chose to supersede the older 5-position switches with one “universal” switch, which could be used on any model. We have noticed that Honda’s release of replacement wiring harnesses for the 250-305s, all came with the “winker” wiring connections included, whereas the US-spec harnesses had winker wiring deleted originally.

S90/CM90-91 switches

A recent question, coupled with some actual hands-on experience, made me think to share some more switch information concerning the early OHC90 models.  Depending upon the application and what kind of dimmer switch is installed on the model, your ignition switch can be either a 2 wire or a 5/6 wire type. When the dimmer switch on the handlebars has just a Hi-Low beam function, the Lights ON-OFF function is controlled by the third position of the ignition switches. When the headlight dimmer switch has the ON-OFF-Hi-Low function, then the ignition switch only needs to be a two-wire type. The wiring harnesses are, of course, completely different in order to match the types of dimmer and ignition switches used.

Well, that is all there is to report on the “optional” ignition switches that you might encounter in your search for NOS electrical parts, for your Benly, Dream or S90 restoration projects.

Happy hunting and look at your potential purchases carefully.

Bill “MrHonda” Silver

The High Price of Free Motorcycles…

Having been a motorcyclist in some form or other for over 50 years, I have owned several hundred cars and motorcycles, but seldom have I had any given to me for free… until now.

In the past month I received a “free” Honda S90 (Super 90) which had been partially used as a dirt bike and was wearing a very unattractive yellow paint scheme. The engine was frozen and we had to cut the drive chain off so we could even roll it into my truck. The last tags on the old CA black plates indicated a 1970 registration date. The bike was given to the man I received it from after the owner was moving out and had to get rid of the poor little Honda 90, which had been sitting in the back yard for many, many years.

The bike was rolled off the back of my Tacoma and onto my new Harbor Freight bike rack for disassembly and evaluation. The bike still wore its speedometer and headlight, plus the stock air filter and carburetor setup. Only the exhaust pipe had been changed to an upswept design with the correct exhaust port angle. Honda made major design changes in the early years, including re-angling the exhaust port exit. Many of the “early” Honda S90 parts will not interchange with the “late” versions. See this site for some of the details: http://s90partspuzzler.blogspot.com/

Ordering gasket kits proved somewhat futile, as the complete kits are all for “late” engines. I eventually had to buy a half-dozen separate gaskets that were “early” model specific in order to rebuild the engine. And that engine build was not an easy task, as it took over an hour of serious work in order to get the piston, which was half way down the bore to come out the bottom of the cylinder. 

Ultimately, the end of the rod wound up being bent and the cast iron sleeve pressed into the alloy barrel had a small fracture line in it from all the violence that occurred during the piston removal.

Fortunately, our local machinist wizard, Bruce Barker, came to my rescue in straightening out the bent rod and later straightening out a pair of fork tubes. Having a guy like that in the motorcycle community is indispensible for these kinds of repairs.

As the S90 came apart, I discovered a damaged swing arm as well as a broken off upper shock mount stud, so after disassembly, the S90 frame was set aside, along with a pair of rusty wheels and a box of other misc parts that were beyond salvaging. In the middle of this adventure, I recalled that a friend who specializes in quality auto body work had a CL90 bike that was pretty complete, but the engine was not repairable for a reasonable cost, so it sat unused for several years. I called about the bike and we struck a bargain where I paid for the bike and also a quick paint job on the original S90 gas tank. 

Slowly, the bike is turning into a hybrid collection of S90 and CL90 parts, melded together to make something out of nothing. Renewing  these small bikes is less costly than most, but when you buy a new piston kit, gasket kit, seal kit, fork seals/boots, handlebars, control cables, battery, petcock and carburetor parts, drive chain, sprocket/hub cushions, tires/tubes/bands, misc rubber parts, headlight and all the other dozens of parts that must be renewed, suddenly the “free motorcycle” has you in debt for $1,000 or more, not including many hours of time and parts chasing. Of course the bike had no title or paperwork, nor did it have a key. Leaving the ignition switch with a local locksmith shop to remove a broken key and supply two new ones left me facing a $50 repair bill. New aftermarket switches are less than $20, so trying to save the old switch wasn’t proving to be a wise move.

The front wheel on the CL90 chassis was covered with fork oil due to blown seals, which kept the front rim looking new, once the old oil was removed. The tire was an original and pumping up the old tube actually kept the tire fully inflated while the bike was on the repair rack. A cheap a/m tire from an eBay seller proved to be problematical as it had a 2003 date code, was somewhat warped from years of storage on the side and was partially full of dirt and debris, which needed cleaning before it could be mounted on the rim. The stock 2.50x18 tires are somewhat tricky to mount on rims, especially getting the valve stem inserted properly.

The engine’s cylinder head had a lot of water that had come up the exhaust port through the aftermarket exhaust pipe, so both valves needed replacing and the seats required re-cutting. In the past year, two different friends gave me misc sets of OEM Honda factory valve seat cutters to fit everything from 50cc to 450cc engines, so getting proper valve seats profiled correctly was easily done here in the shop.

The transmission required some mixing/matching of parts and pieces to get a good set of parts for the manual transmission function. Honda changed the root sizes of the shaft splines, so you can’t just swap on a late gear on an early shaft. Eventually, the transmission had one early shaft of gears and one late shaft of years, all being selected by an early style shift drum and forks.

The whole engine as a big ball of corroded aluminum, requiring full disassembly, then soaking in Simple Green to degrease. Then a nearly 100% straight phosphoric acid bath was used to neutralize the scale and aluminum corrosion. Several hours of gasket scraping and wire brush work was needed to get the parts close to original condition. All this work for a “free motorcycle”!

Oddly enough, the carburetor bowl was clean as a whistle inside, but the float was dented in so a replacement was ordered. The petcock was rebuilt with new rubber bits and all new seals and gaskets were used wherever needed.

The speedometer showed some 11,000 miles so there was little surprise to discover that the brake shoes were severely worn down. Honda used the same shoes for the little Cub 50s and the 90cc series machines, so the parts are readily available. Once the fork tubes were straightened out, new seals, fork boots and oil were used to freshen up the front end. Some cool aftermarket low handlebars were sourced from an eBay seller, which will go along with the “café” theme of the bike. An interesting metal front fender was on the bike when received and both fenders were painted a deep metallic burgundy color.

Hot on the heels of the S/CL90 project, a friend gave me a 1983 XL200R Enduro with a title (nice for a change), showing just 4400 miles on the dusty speedometer. It was another “backyard” bike that was rode hard and put away wet many years ago. The gas tank has a HUGE big dent in the side, the whole thing was dirty, dusty and all scratched/dented up from top to bottom. The rear tire was oversized and bald in the middle while the front tire looked almost unused. The engine, of course, was seized up solid, so a whole bike teardown was in order. The rear fender was sporting an old Suzuki tail light, mounted up on a bent-over rear fender. The fender assembly actually has a thin metal reinforcement below the plastic outer fender. The fender was disassembled and a decent used plastic fender section purchased on eBay. The inner fender support was taken to my friend Rob North for some welding up of the many small cracks and reinforced in the middle with a big flat washer.

During the engine removal process, I managed to drop the entire engine on the big toe of my left foot, which was wearing Crocs at the time. It would have been so much easier and safer to just have put a jack beneath the engine cases, but somehow I thought I could just wrangle it out of the frame with one hand.

With the engine sitting on the ground, I was able to disassemble the top end for inspection. Despite a full air filter assembly in place, somehow water had worked its way down the intake port and into the cylinder, sticking the piston in place, mostly in the down-stroke position. There was a lot of rust, carbon and other debris on top of the piston which was vacuumed off at first. A good spray of the WD-40 penetrating oil product helped to lube things up I guess, but to my surprise a couple of medium whacks with a brass drift knocked the piston loose and the cylinder slid right off the engine with little effort! That doesn’t happen very often!

A .75mm oversized piston kit was procured from an eBay seller as well as a top end gasket kit which was ordered for this model, but a KX80 kit showed up instead. The seller finally replied to my pleas for the correct kit and it was dispatched forthwith. The cylinder was taken to my reliable machine shop buddy, who called back the next day saying that there was still some staining on the cylinder liner and “Oh, by the way, I dropped the cylinder on the floor and broke off a fin.” I might have been more upset if this was a Concours machine, but as an old beater dirt bike I wasn’t too concerned.

A proper-sized rear tire was purchased through the local dealer and installed while I waited. A new chain and battery await the reinstallation of the engine. The carburetor cleaned up okay and a new aftermarket petcock purchased to bypass the non-repairable OEM unit.   

Current status 9/21/16:  After wrestling with the engine installation for way too long, I finally realized that I had mis-installed the two engine mount bolt spacers, which are about a ½” difference in length. Once that little “correction” was made, the engine bolts all started to magically line up as they did when the bike was built at the factory! Duh! Anyway, the bike is about 80% reassembled now with prayers for an actual start-up event in the next few days.

The S/CL90 project is awaiting some throttle pieces and point plate cleaning and installation.

Meanwhile, my pride and joy 1965 Mustang 2+2 fastback, which has been pretty reliable all summer, suddenly belched up about a quart of ATF on the driveway. Crawling underneath revealed little in the way of a source and it wasn’t actively leaking when inspected. A call to the transmission shop that had done a service on it a few months ago mentioned that when the cars are not run regularly (and parked nose uphill) the torque converters will drain back into the transmission case, overflowing out the vent fitting! Barring any leaks at the speedo cable drive fitting o-ring, that is the probable cause of the leak. The shop has been busy, but thought they might be able to squeeze it onto a lift for Thursday morning.

Bill “MrHonda” Silver

Vintage Honda Tips, Tricks, Tests and Troubleshooting

An wide array of vintage Hondas have shuttled through Casa De Honda since the first of the year and with each one there is the gift of knowledge to be learned and shared. Understanding the basics of how mechanics and electrics all work on the older machines is a sound foundation to work from, especially when the bikes try to pull a fast one on you. Despite owning hundreds of bikes over 50 plus years, there is always something unexpected to discover.

I started out the year with a couple of CB92s, one a race-kitted 1960 model and a 1961 bike with an odd provenance. The 1960 bike had a California assigned engine sticker on the motor apparently due to an engine change, perhaps because of a blow-up moment. While the top case was correct for the year, the bottom case was actually from a CA95, which has different muffler mounts cast into the part. These were not compatible with stock CB92 exhaust parts, so they were removed to aid in proper fitment of the megaphones. The 1961 bike was a mystery, in that the original MSO paperwork from American Honda showed the bike as a CB92R model, which comes with all the factory race-kit parts. The MSO was sent to a dealer in MA, where the dealer sold the machine to a young woman. The bill of sale showed a note about the inclusion of stock mufflers in the deal, but the only problem seemed to be that the bike was NOT a CB92R. Apart from an add-on tachometer mount, the bike was a stone-stock CB92 street bike. There was no sign of CB92R parts anywhere else on the bike. I sold it to a local friend and wound up rebuilding the engine and it was all stock inside.

On the other hand, the 1960 bike did have YB92 pistons, which require side-cap spark plugs because the domes are so tall that they interfere with the normal spark plug gaps. The valve spring retainers were alloy parts on both engines, which apparently were stock for the first 2 years. The intake port had been hogged out to fit a larger carburetor, but the original 18mm mixer was replaced with just a 20mm CA95 unit which was later done at the factory as an upgraded part. I expected to see a YB mark on the camshaft, but it appeared to be a stock unit. The engine was freshened up and sounded like a mighty mite when it was fired off in the back yard. That bike was sold to a man in Indonesia.

Simultaneously, a nice, original-looking CL72 popped up on eBay, portrayed as a 1964 model; however the tail light was a “short-lens” unit which made me think that it might be an earlier model. It turned out to be a late 1962 machine, confirmed once I was given the serial numbers. Few people were aware of the fact and I was able to buy it at a reasonable price. Both the CL72 and CB92 purchases were done in the dead of winter and the bikes were located in New Hampshire and Montana, so cross-country transport seemed out of the question for immediate delivery. However, the U-ship system managed to contact some willing drivers and the bikes did arrive within a few weeks of purchase.

The Scrambler had most all of the original patina and only needed few air filters/tubes and a general going-over to be serviceable. On a couple of occasions, the bike was hard to start and the float bowl on the right side was found to be empty despite a freshened up petcock and a half tank of fuel. Flipping the float up and down didn’t seem to affect it, so I blew into the fuel tank opening and suddenly the fuel was flowing once again. The bike ran well after that, so whatever little blockage seemed to have worked itself out.

I had a “time-out” in February for knee surgery, but was back in the saddle within a month. But in the interim before surgery a derelict CB77 popped up on the local Craigslist. The bike had low miles, but had been poorly stored for years and at some time, the bike had been lying on its side causing the protective oil film to be lost from much of the engine’s internals. The engine was “stuck” and the transmission wouldn’t shift. After a laborious disassembly most of the engine’s internals were severely rusted with the shift forks and drum basically a single, unmoving unit. Lots of time was used to clean parts and replace the whole transmission and shift drum with good used parts. I had a spare top end that was mostly NOS parts and had been used sparingly on another engine build, so the whole original top end was replaced with later model parts.

I don’t advertise doing repair work, but people do find me by word of mouth, so various interesting repair jobs show up. One was a hard-starting XL350, which indicated that power was coming out of the stator coils, but there was no spark at the plug, even after replacing the coil and condenser. In the end the stator’s primary coil was somehow defective and a good used one fixed the no-spark problem.

Something that shows up often is hard-starting, poor performance due to poor battery function or maintenance. At least four bikes have arrived lately with lead-acid batteries that were basically dry inside. Recently a cherry, Scarlet Red Honda S90 with 2500 original miles was brought by for poor throttle response, but would start and idle okay. Everything was set to specs by another shop, but apparently they failed to check the battery voltage and condition. Even with about a cup of distilled water added to the battery, it only showed 4 volts available. After a few hours on the charger it came up to 6 volts and once installed the bike ran great. There was a little hesitation off-idle that was eventually traced to a low float level coupled with the needle clip being in the wrong slot. With a fresh battery and carb adjustments it ran perfectly, but ALL of the light bulbs were blown out due to the engine running with a dead battery.

A nice-looking Z50A came to the shop due to “not shifting” problems. The bike had been stored for years out along the coast, but inland a mile or so. The whole history was unknown, but the owner got it up and running, then discovered that it wouldn’t shift gears no matter what he did.  He did mention draining the oil which looked terrible and then refilled with ATF to try to flush out the old gunk inside. He drained it again and brought it over for a diagnosis. Once the clutch cover was removed, the “high water” line where the old oil had been sitting spelled more than just another oil change in order.

Most of the internals were pitted with rust and there was an eighth-inch of sludge at the bottom of the cases.  Rust attacked the shift drum, just like the CB77 had suffered, locking the shift forks in place. The camshaft lobes were pitted, as were several of the transmission gears. Even the crankshaft bearings had rust on the ball bearing races and retainers. The cheapest way to address most of these problems was to just replace whole units. There were killer deals on eBay for a complete cylinder head ($61 delivered), a four-speed transmission for $155 and a couple of crankshaft main bearings for $22. The camchain was replaced, as well. The cylinder was still on STD bore size and the piston was still a good fit. Fresh rings brought the end gap down to specs, so a good honing was all the machine work needed. A local shop just opened offering wet blasting of the engine cases, so the main motor castings went to them for a good scrubbing and the whole motor looked pretty nice at the end. In the end, this engine repair ran to over $900. 

When replacing clutch covers on any of these engines using gaskets, it is always wise to start all of the screws in a few turns before cranking them down tightly. Gaskets have a tendency to shift around enough to where one or two of the screw holes are not matched up with the cases without a little massaging of the gasket while the outer case is still loose. Get all the screws started, then you can go to town in tightening up the fasteners.

With today’s alcohol injected fuels, it is imperative to run the bike regularly or drain the fuel out of the float bowls, using stabilizer to maintain what is still in the tank. The alcohol attacks the old-school rubber carburetor parts and the float bowl gaskets invariably will swell up once they are removed from the carburetor body. Best defense against this problem is to have duplicate float bowl gaskets on hand. Once the alcohol dries out of the old gaskets, they will shrink back to normal size after a day or two and you can reuse them once again.

For owners of the 250-305 engine series machines, there are a lot of tips to help keep the bikes running well. Fresh fuel is a must, and be sure that the gas cap vent holes are open and clear. Check your ignition timing with the engine running, using a dynamic automotive timing light. Static timing doesn’t take into account for weak advancer weight return springs and side-play in the point cam, where it turns inside the right side camshaft. Over-advancing the spark timing will cause engine seizures under full-throttle. The CB77s seem to like running #140 main jets on the new fuels vs. #135 stock sizes. Check your wet-cell battery levels at least once a month.

If you are assembling the top end of the 250-305s, a trick to help keep the cams steady is to loosen up the valve adjuster screws while the camshaft is being timed to the crankshaft. The right side cam lobes are on OVERLAP (not compression stroke) when the camshaft is being timed, so both valves are slightly open on that stroke. Turning the adjuster screws in slowly by hand will allow the spring-loaded rocker arms to put pressure on the lobes. The adjuster screws can be manipulated back and forth on the intake/exhaust sides to a point where the camshaft sprocket is dead level with the cylinder head. The left cylinder exhaust rocker arm must be backed off as well, but the intake valve on that side is closed so no affect on the cam timing. You will find that the camshaft is rock steady once you have it centered with the RH side adjuster screws. Attach the camchain when the right side piston is at TDC (T mark on the rotor) and your engine cam timing is perfectly correct.

Honda’s rectifiers can be replaced with little Radio Shack bridge rectifiers or some companies now offer solid state regulator/rectifiers which allow the charging system to run full blast all the time, but still regulated to keep from overcharging the battery. Honda’s system only adds in the last leg of the stator when the lights are turned ON. The new solid-state units rout all three AC legs into the control unit all the time and then it decides how much voltage to allow into the system to keep the battery fully-charged.

Remember to use Honda GN4 engine oil which is specially formulated for motorcycle engines. We “old-timers” always remember using Castrol GTX car oil in our bikes back in the 1970s-80s, but it really doesn’t do the job for long, due to the shearing forces in the transmission gears. Use a motorcycle-rated oil in your motorcycle for long life and best results! Always take a moment to check the oil level, tire pressures, chain adjustment and fuel levels before you ride out on your vintage machine.

Bill “MrHonda” Silver

MrHonda moves to Blogspot

After 4 years of cranking out stories for little compensation on the old Examiner.com site, they went defunct and are off the web altogether along with my 400 stories.

After taking some time off, mostly getting buried in new projects I decided to search around for a new place to park my words.

Ironically, I have often been referred to as the Honda Guru, so I discovered MrHonda.guru as an new identity so there you go....

Current projects are a "free" 1983 XL200R bike which now has a new piston/rings after 10+ years of poor storage after the poor thing was beaten to death...  A "free bike" story is in the works...

Before the XL200 came a "free" Honda S90, early model version which uses a lot of unique parts that were changed out in later editions. The chassis was pretty badly corroded, but I recalled that I had disassembled an engine for a friend's CL90 Scrambler, so contacted him, bought his remaining parts and am marrying the CL chassis to the S90 engine, using the S90 fuel tank and CL90 seat. Wound up with WAY too much time and money into this thing and it doesn't have any paperwork at all, since the last tags on the CA black plate are 1970... another backyard sitter for too many years.

Seeking some good used S90 parts from my friend Ron Smith resulted in me owning a 1964-5-ish C110 Sport Cub project!

A call from a Honda enthusiast in OR, yielded a road trip for him to bring down a domestic C72 Dream engine, complete with rotary gearbox feature. It is all apart now, awaiting cleaning, new rings, gaskets, seals, a few internals and a vapor blasted and polished finish.

The man who gave me the XL200 also has a 1973 CB125 that he takes out to the desert for slow trail rides, along with his CT90 which was recently here for a little tuning. The CB125 engine has a somewhat ominous knocking sound inside, so the owner wants that one torn down for evaluation and repairs.

In the previous month, I had a CL77 here for a top end job, followed by a CL72 needing a bottom end transmission overhaul. It has been a busy couple of months!

Bill "MrHonda" Silver