The factory service manual I ordered from Yamaha Canada turned out to be a spiral-bound photocopy of the original along with a new laser-printed cover suggesting that the contents apply to the model years 1982 to 1985. In fact, the manual is specific to the 1982 CV80J. I know because later I found an original service manual on eBay and compared it to the reprint. Nevetheless, my service manuals helped with some of the details listed below. The Yamaha USA website and other sources provided additional information. But there are still plenty of pieces missing from this puzzle. As you can see, I have yet to dig up details for some model years. Nor have I resolved why there were apparently two versions of the CV80E, in 1981 and 1982, or why parts catalogues available on Yamaha's US website indicate two primary ID numbers for some models—without explanation.

To further confuse matters, Yamaha evidently had different serial numbers for specific geographic regions. A service manual for the CV80J that was published for the European market in English, French, and German refers to starting serial numbers 13Y-000101 in England and 14E-000101 in France (no mention of a number for what was then West Germany). And from a source in New Zealand I found a supplementary service manual that indicates serial numbers on CV80Js for Oceania started with 14J-000101. Oddly, the same manual indicates 14X-000101 for territory that was "not Oceania."

By the early 1980s, Yamaha USA adopted the VIN system to identify frame numbers. I'm not entirely sure what happened elsewhere in the world, but I suspect that IBM numbers continued to influence Yamaha's identifying conventions to some extent. (IBM numbers were used for parts specific to a particular year, so for example a wire harness assembly for a CV80K is listed as 13T-82590-20-00. But many parts for the J, K, L and other models should be interchangeable. In fact, many parts on my CV80J are stamped with "5G3"—a number given to previous models.) The supplementary service manual I found in New Zealand is identified as part number 14J-28197-20. Compare that to the part number for my service manual, 14M-28197-70, or the number for the multilingual manual referred to earlier, 13Y-28197-80. That said, in the charts below I suppose I could simply list known country prefixes (and part suffixes?) and let users fill in the blanks for specific part numbers. But I am not yet convinced that my hypothesis (regarding Yamaha's use of IBM numbers for identification purposes) has been sufficiently tested. Nor do I have enough country-specific numbers to justify the exercise by suggesting it will make the charts any more legible.

One other remark concerning manuals: at one point Yamaha introduced a "LIT" prefix for numbering its product-related literature, but the system was not maintained in all markets. I was informed at a local dealership that Yamaha Canada, for example, has not used LIT numbers to identify manuals for over 20 years. However, Yamaha USA continued to use it—perhaps with too much enthusiasm. I can't explain why I have found multiple LIT numbers for some manuals.

For all that, as far as I can tell Yamaha did not change the CV80 very much from year to year—at least in North America. A significant exception was the type of Mikuni carburetor used. Variations of a "Mikuni VM13" are found and some Yamaha promotional material indicated the CV80 shipped with a Mikuni VM16. In any case, with different carburetors there were also slight differences in the way the bimetal control valve attached to the manifold, which might have affected the way hoses connected.

And of course, in Japan and for the European market CV80s were equipped with integrated front and rear turn signals, or "winkers" as they are called.

I will continue to update details of specific models as I receive new information. Note that where a VIN is used in the chart below, the 9th digit—a check digit that varies according to the production (serial) number at the end (last 7 digits)—is shown in parenthesis. The 10th digit of the VIN is the year code: 1981=B; 1982=C; 1983=D; 1984=E, 1985=F; 1986=G, 1987=H. Many letters, such as I, O, Q, U, and Z, were not used to avoid confusion with numbers. There's at least one anomaly in my accounting, as the sharp-eyed reader will soon see. According to the system, the initial frame number shown for the 1986 CV80S must be incorrect.

Feel free to contact me if you have additional information, comments, serial numbers or parts numbers you want to pass along to help shed additional light on Yamaha's CV80 models.

Yamaha USA has put parts catalogues for its scooters—including the CV80s—online. If you want to purchase a hard copy of an owner's or factory service manual, try a local Yamaha dealer first. In the US, you can order some manuals directly from the Yamaha Motors website. But expect to pay a hefty price: US$30-$60 depending on the manual. Other sources include:

• www.speedandsportinc.com
• www.repairmanual.com
• www.motorcyclememories.com

Of course, you should always keep an eye on eBay. Sign up and make "Yamaha scooter" one of your favourite searches. That's how I found an original CV80J service manual in very good condition for a good price.

The following notes are adapted from the Yamaha USA website:

What information is contained in an Owner's Manual?
The Owner's Manual, also called the Owner's/Operator's Manual, is intended to provide a good basic understanding of the features, operation, and routine maintenance of the machine. Owner's Manuals contain important safety information, and should be read by everyone who plans to use the machine.

What information is contained in an Owner's Service Manual?
The Owner's Service Manual is intended to provide a good basic understanding of the features and operation of the machine. It has important safety and operation information that should be read by everyone who plans to use the machine. Experienced mechanics can use the technical information it contains as a reference during service and repair of the machine.

What information is contained in a Service Manual?
The Service Manual provides technical information to use as reference during service and repair of the machine. The manual is intended primarily for trained mechanics at Yamaha dealers. It is not possible to include all the knowledge a mechanic needs in one manual, so anyone using this manual should have a basic understanding of mechanics and the techniques to service and repair the machine. Repair and maintenance work attempted by anyone without this knowledge could render the machine unsafe and unfit for use. Your Yamaha dealer may also have received additional service information not included in the manual, so check with your dealer before servicing the machine.

What information is contained in a Supplementary Service Manual?
The Supplementary Service Manual is intended to provide technical information the original or previous manual does not provide about new features or changes to existing components. You need both the original manual and the supplementary manual to do service and repair work because the supplementary manual provides only the new or different procedures or specifications needed. Your Yamaha dealer may also have received additional service information not included in the manual, so check with your dealer before servicing the machine.

What information is contained in an Assembly Manual?
The Assembly Manual contains information required to unpack and assemble Yamaha motorcycles correctly prior to delivery to the customer.

The following information was obtained from a microfiche for the CV80J and compared with details found in my parts catalogue for the K and L models.

The codes are handy for more than simply matching when doing touch-ups. You can use them to determine if a part you find listed on a website, for example, will suit the model you own (and save you writing to ask, "What colour is it?"). The parts catalogue provides multiple numbers where appropriate, as shown by the listing for the instrument panel upper cover:

Now, to confuse matters, the Color-Rite Master Paint List for Yamaha differs somewhat and doesn't even acknowledge the existence of a "Crystal Silver." Here's what I found on the Color-Rite website:

Go figure.