I am looking for a Honda Service Bulletin that would have gone out in 1971 or 1972...Concerning shifting problems with the 1971 CB500 Four...It would have announced a 'kit' that replaced certain parts to correct or minimize the problem...I
understand that the Service Bulletins previously posted here have all been taken down, so I'm asking for a link or a copy of the Bulletin involved.
I bought a CB500 Four back in 2006, and I'd like to see what serial numbers got the 'fix' from the factory (before the redesign that was reflected in CB550's), and how dealer-applied 'fixes' were identified...Maybe with a stamp somewhere that
would be obvious to a Honda mechanic...
Here's the story...Feel free to go on to something else, as this is rather long, and I did post a thread on it years ago...
I was stationed on Okinawa in 1971, and first saw the then-new CB500 Four in a Ryukuan cycle shop. I really liked it, and when I was discharged in Dec '71, I decided to get one ASAP. Getting settled took me a few months, but by about March/April '72 I had the money [about $1600 IIRC]. The local Honda dealer, Honda Village in Niagara Falls NY had several new unridden CB500's on the display floor. A salesman (co-owner it turned out) named "Whitey" showed me several floor models. I chose a Garnet Brown model. I installed a couple accessories to it, like a finned oil filter cover and a triple-tree ignition switch mount.
I rode it cautiously for the first 500/750 break-in miles, and then felt ready to try it out. IIRC it would do 105mph top end. I rode it for about 6 weeks, and one day while leaving my GF's house, shifting from 1st to 2nd, the entire drive train
locked up completely. Caught me by surprise, and I barely kept it upright while skidding to a stop. Not very fast, maybe 10-15mph. I poked at the shift lever while rocking it back & forth, and finally got it into a gear. It started up normally,
and I drove away, thinking it was probably my fault.
About another 5 or 6 weeks later, it happened again. 1st to 2nd shift, everything locked up. But this time I had my fingers on the clutch lever and disengaged the clutch, and rolled to a stop, engine still running. I was once again able to shift up
& down until I got a gear, and was then able to shift normally and ride it home.
I subscribed to a motorcycle newspaper/tabloid thingy back then (called "Cycle News" I think), and shortly after my 2nd shift episode, I read of a problem with 500 Four shifters/transmissions, where they selected a 'false neutral', and that dealers
had been alerted about this problem and a dealer-installed 'kit' to fix it, under warranty. The next day, I took my 500 Four to the dealer and explained what happened. "Whitey" told me it only applied to 1971 500 Fours, and mine was a 1972 model and already had the new parts installed at the factory. I was told my problem was not covered under warranty and that if I wanted my 500 Four torn down for inspection, it would cost me $75 [IIRC in 1972] just to disassemble it. I didn't have that kind of money right then (I was back in college), so it never got 'dealer torn down/inspected'.
About a month later, it happened again - but this time going from 2nd to 3rd, and I was doing ~35mph...Again I pulled in the clutch, and drifted to the shoulder of the road. In all this time, I had not put a lot of miles on it; no trips, no daily commuting; just pleasure rides.
Fall was here, and I put the Honda away for the Winter (I'm just North of Buffalo NY, snow capital of the world). Spring of 1973 I sold the cycle. I didn't trust it anymore. I bought a Triumph Daytona [500 dual-carb twin] and later sold that &
upgraded to a 650 Triumph Bonneville.
About a year later, I got a letter from a law firm inviting me to join a class action lawsuit against American Honda Motor Company. It stated that my 500 Four VIN was identified as one that the lawsuit alleged was involved in a fraudulent scheme by AHMC to re-register certain unsold 1971 models as 1972's. AHMC had asked dealers to send in the VINs of unsold cycles and AHMC would send an 'updated' Certificate of Origin stating they were 1972 models. Since mine was one of the VINs identified, I joined the lawsuit. About nine months later, I was informed by letter that AHMC had settled out of court, and I received a check for [IIRC] $65, which was explained as the difference between resale value of a '71 vs a '72.
That was the end of my involvement with that particular Honda 500 Four, but I've always felt I had unfinished business with that model. So when a 500 cropped up in 2006 (no 550's available here at that time), I bought it.
I'm hoping this one has the 'fix' already applied to it, either by the factory or a dealer. I'm hoping the Service Bulletin identified what VINs were affected, and how the 'fix' was marked.
Thank you all for your patience!
