Motorcycle VIN Decoder: Bike and Dirt Bike VINs, Year Chart

A motorcycle VIN decoder reads the 17-character vehicle identification number stamped on a bike's frame and turns it into the maker, model, engine size, model year and plant. Every street motorcycle built for the US since model year 1981 has one, usually on the side of the steering head, and you can decode it free against NHTSA's vPIC database.

This guide shows where to find the VIN on a motorcycle, what each character means under federal rules, the manufacturer codes for 10 brands sold in the US, and a full worked decode. For the general rules that apply to cars too, see our guide on how to read a VIN. To decode a bike right now, paste its VIN into our free VIN decoder.

What a motorcycle VIN decoder tells you

Motorcycle VINs follow the same federal standard as car VINs, 49 CFR Part 565. Manufacturers file their VIN-decoding data with NHTSA, which publishes it in the vPIC database. A decoder looks up each block of the VIN against that data.

When we queried NHTSA vPIC in October 2026, a typical motorcycle decode returned:

• Make and manufacturer, for example Harley-Davidson Motor Company
• Model and series, such as Street Glide (FLHX)
• Body class, such as touring or sport
• Engine: displacement in cc, number of cylinders, and often horsepower and cooling type
• Model year and plant city and country
• A check digit result that tells you if the VIN is internally valid

What a VIN does not tell you: mileage, accident history, liens, theft or open recalls. Those come from separate checks, covered at the end of this guide.

Where is the VIN on a motorcycle?

On most motorcycles the VIN is stamped into the frame on the side of the steering head, the short tube behind the front forks that the handlebars pivot on. Turn the bars fully to one side and shine a flashlight on it. Kawasaki's own customer support FAQ states this plainly: "On all motorcycles it is stamped on the side of the steering head."

Federally certified street bikes have a second place to read it: the certification label. Under 49 CFR 567.4, a motorcycle's label must be fixed to a permanent part "as close as is practicable to the intersection of the steering post with the handle bars." The label must show the VIN and the month and year of manufacture.

The engine number is not the VIN. It identifies the engine only, and engines can be swapped. Titles, registrations, recalls and theft records all key off the frame VIN, so always read that one. Off-road machines put the VIN in other places; our ATV VIN decoder guide covers quads and side-by-sides, and our VIN location guide covers cars, trucks and trailers.

The 17 characters of a motorcycle VIN

Part 565 splits every VIN into four sections. Most rules are the same for cars and motorcycles, but three details differ, and they matter when you decode a bike.

Positions 4–8 for motorcycles. Table I of § 565.15 lists what the vehicle descriptor must make decipherable for each vehicle type. For a motorcycle it is "make, type of motorcycle, line, engine type, and net brake horsepower." Cars must encode body type and restraint systems instead; motorcycles must encode horsepower. The rule adds that encoded horsepower must be within 10 percent of the actual figure, with a special case for bikes of 2 horsepower or less. Bikes from model year 2009 and earlier follow the older Subpart C rules, whose list for motorcycles leaves out make. The manufacturer chooses which characters carry which attribute, so the codes differ by brand. That is why you need a decoder rather than a universal chart.

No alphabetic seventh character. For cars and light trucks, position 7 must be a letter on 2010-and-later vehicles. That rule does not apply to motorcycles. It has a knock-on effect on reading the model year, explained below.

Four numeric characters at the end. Cars must end in five numbers. Motorcycles, like all other vehicle types, must end in four.

Allowed characters. Every VIN uses only capital letters and digits, and never the letters I, O or Q.

Motorcycle WMI codes for major brands

The first three characters tell you who built the bike. These are WMIs that NHTSA vPIC lists with vehicle type "Motorcycle" for each brand, from our DecodeWMI and GetWMIsForManufacturer queries in October 2026. Most brands hold several; the ones below are the main codes for each.

The first character is the region code, so J is Japan, W Germany, Z Italy, S the UK, V Austria and 1 or 5 the United States. The WMI identifies the manufacturer, make and vehicle type, not always where the bike was built. Position 11 identifies the plant, which Part 565 defines as the plant where the manufacturer affixes the VIN. Kawasaki is a good example: full VINs starting JKA or JKB can decode to its Lincoln, Nebraska plant for off-road models and to Akashi, Japan for sport bikes. Our brand guides go into each maker's codes: Kawasaki, Yamaha, Honda motorcycle VIN decoder, Suzuki motorcycle VIN decoder and KTM VIN decoder.

A worked motorcycle VIN decode

Here is a full decode of a real VIN pattern. It comes from NHTSA recall report 24V-672, which lists a range of 2024 Harley-Davidson touring bikes beginning 1HD1KB71. We replaced the serial with 100001 and recalculated the check digit, giving 1HD1KB716RB100001. vPIC decoded it as follows in October 2026.

Note the horsepower figure. It is there because Part 565 requires net brake horsepower to be decipherable from a motorcycle VIN. For the rest of Harley's code system, see our Harley-Davidson VIN decoder.

How the check digit works

The check digit lets anyone catch a mistyped or altered VIN. The method is set out in § 565.15(c):

1. Convert each letter to a number: A=1, B=2, C=3, D=4, E=5, F=6, G=7, H=8, J=1, K=2, L=3, M=4, N=5, P=7, R=9, S=2, T=3, U=4, V=5, W=6, X=7, Y=8, Z=9. Digits keep their value.
2. Multiply each position by its weight: 8, 7, 6, 5, 4, 3, 2, 10, 0, 9, 8, 7, 6, 5, 4, 3, 2.
3. Add the 17 products and divide by 11. The remainder is the check digit. A remainder of 10 becomes X.

For 1HD1KB716RB100001 the products are 8, 56, 24, 5, 8, 6, 14, 10, 0, 81, 16, 7, 0, 0, 0, 0 and 2. They add up to 237, and 237 divided by 11 leaves 6, which matches position 9. If a seller's VIN fails this check, either it was copied wrong or something is off with the paperwork or frame.

Reading the model year on a motorcycle

The 10th character is the model year. The codes run A for 1980 through Y for 2000, then 1 to 9 for 2001–2009, then start again at A for 2010. So 2024 is R, 2025 is S and 2026 is T. Our VIN year chart lists every code.

The catch is that the letters repeat every 30 years. On cars and light trucks, Part 565 settles which cycle applies: a numeric 7th character means 1980–2009 and a letter means 2010–2039. That rule covers passenger cars, MPVs and trucks only, not motorcycles. So an R in position 10 of a bike's VIN could mean 1994 or 2024, and the VIN alone does not say which.

vPIC flags this. Our decode of the Harley example came back with the note that "the Model Year decoded for this VIN may be incorrect," and the vPIC API documentation recommends always sending the model year with a decode request. In practice the model, engine and styling usually make the answer obvious. When in doubt, check the year on the title and the month and year printed on the certification label.

Motorcycle and dirt bike VIN year chart

This chart works for every brand, including Harley-Davidson, Honda, Yamaha, Kawasaki and Suzuki, and for dirt bikes that carry a 17-character VIN. Each code has two possible years. Pick the one that fits the bike.

The letters I, O, Q, U and Z and the digit 0 are never used for the year. A number in position 10 is the only case with one answer, because digits 1 to 9 cover 2001–2009 and are not reused until 2031. Remember this is the model year, which can differ from the month and year the bike was built. The certification label shows the build date.

Suzuki and other Japanese brands. A Suzuki VIN starting JS1 with an L in position 10 is a 1990 or a 2020 model, and the engine and bodywork make it obvious which. The same reading applies to JYA (Yamaha), JKA or JKB (Kawasaki) and JH2 (Honda).

Dirt bike VIN decoder: what changes off-road

A dirt bike VIN uses the same 17-character layout as a street bike, and a modern motocross or enduro bike from Honda, Yamaha, Kawasaki, Suzuki or KTM will usually decode. Three things work differently.

Where to find it. On most dirt bikes the VIN is stamped on the steering head, the same place as on a street bike. Mud, number plate backgrounds and fork guards often hide it, so clean the area gently rather than scraping. The engine number is stamped separately on the crankcase.

What the decoder returns. Off-road-only bikes are not built to the Federal Motor Vehicle Safety Standards, so vPIC usually adds a warning that the vehicle is not a certified motor vehicle. That warning is expected and does not mean the VIN is fake. Our ATV VIN decoder guide explains the error code in detail. Off-road-only bikes are also not required to carry the federal certification label that street bikes have near the steering head, so the VIN stamp and the title or MCO are your sources for the year.

State rules on off-road VINs. Some states read road and emissions status from the VIN at registration. California's REG 31 instructions, for example, say a 2003 or newer off-highway vehicle with a "3" or "C" in the 8th position of the VIN is non-complying, the class California registers with a red sticker. California also says an off-highway motorcycle cannot be converted to street use unless it was manufactured as dual-purpose. Our California VIN verification guide covers the paperwork.

Free dirt bike VIN checks. Before you buy a used dirt bike, decode the VIN, confirm the year with the chart above, and run it through NICB VINCheck, which is free and searches theft and salvage records reported by participating insurers. A VIN that is ground off, restamped or does not match the paperwork is a reason to walk away.

Pre-1981, custom and low-volume bikes

Pre-1981 motorcycles. NHTSA says vPIC "is intended for use on Model Years 1981 and forward," and vehicles from before the 1980s VIN standard are not decoded. Older bikes carry frame and engine numbers in formats each maker chose for itself. A modern decoder will reject them or return nothing. For these, rely on the title, the manufacturer's historical records and marque clubs.

Low-volume builders. For model year 2010 on, Part 565 defines a low-volume manufacturer as one building fewer than 1,000 vehicles of a type a year. These makers put a 9 in position 3 and use positions 12–14 as the rest of their identifier, so only positions 15–17 are a serial number. vPIC lists six-character motorcycle identifiers like this, for example 1Z9247 for a small US custom builder. Custom and kit bikes may also carry a state-assigned VIN rather than a factory one.

Replacement frames. Because the VIN lives on the frame, a new frame raises the question of which number the bike now carries. Manufacturers generally will not stamp a fresh VIN. Kawasaki's support FAQ, for example, says it "does not issue duplicate VIN or frame numbers" and sends owners to the state where the vehicle is registered to get a new VIN for a replacement frame. If you are looking at a bike with a state-issued VIN, ask for the paperwork that explains why, and expect a decoder to return little or nothing for it.

VIN checks before you buy a used motorcycle

A decode confirms what the bike should be. These checks tell you what has happened to it.

1. Match the VINs. Read the VIN on the steering head and the certification label and compare both with the title character by character. Ground-off, restamped or mismatched numbers are a reason to walk away.
2. Decode it. Run the VIN through a decoder, such as the free one on our home page, and confirm the model, engine size and year match the ad.
3. Check theft and salvage records. NICB VINCheck is free and shows whether a member insurer has reported the VIN as stolen and not recovered, or as salvage. Our NICB VIN check guide explains what the results mean.
4. Check open recalls. Under 49 CFR 573.15, any maker that sold or imported 5,000 or more motorcycles in the US in the current or prior calendar year must offer a free recall search by VIN. You can also use NHTSA's recall lookup, which searches the major car and motorcycle makers. Our guide to recall checks by VIN walks through both.
5. Get a history report if the price justifies it. A paid report can add title brands and past registrations that a free check will not show.

For a dirt bike, quad or side-by-side, the same steps apply, but vPIC coverage and decoded fields vary for off-road models, so confirm road-use status with the manufacturer and your state. The ATV guide linked above covers those machines.