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I do not sell my motorcycles!
Whether you’re after a 1970 H1 500, a 1972 H2 750, a 1973 Z1 900, a 1978 Z1R, a 1979 KZ1000 MKII, or any other Kawasaki, I am a collector and the only thing you will get from any true collector is very good advice.

As a lifelong collector, I’m always pleased to offer advice to any beginner who shares the same enthusiasm. Here’s some guidance for anyone looking to buy a classic motorcycle.

Advice: It's 2025 and buyer beware has never been more relevant.
Scammers are increasingly sophisticated, and even sellers with excellent reputations and good reviews can mislead buyers. Always verify before you pay, a little caution can save a lot of regret.
It’s wise to remember the old saying: “A fool and his money are soon parted.”

Advice: Don’t take your bike apart unless you’re sure you will finish it.
Know exactly what you're getting into before you start.

There’s nothing worse than ending up with someone else’s “basket case”, The one they swear is “all there” in 5 crates, 2 totes, 18 zip-lock bags, and 4 coffee cans. Sure, it was all there, 15 years and 2 house moves ago.
In reality, about 90% of it’s there and none of it’s labeled. You’ll have no clue which bolt belongs to which part. Taking on a basket-case motorcycle is a substantially greater restoration challenge.

Advice: Know your budget before you buy a project, or consider buying a restored motorcycle instead.
Plan your restoration costs carefully, accounting for every part and expense. For tasks you can’t do yourself, like chrome or paint, call around and get real quotes instead of guessing. Don't forget to estimate the time frame for completing the project. Once you have your total projects cost estimated....double it. Once you have your timeframe estimated....triple it. No hobby restoration comes in under budget or finishes on time. Always expect unexpected costs and surprises when restoring a bike that’s been off the road for 25 years. Trust me, nothing ever goes 100% smoothly as planned.
Professionally restored motorcycles are very expensive, because they cost a fortune to properly restore.
In many cases, restoring a barn find motorcycle can cost more than buying one fully restored. For the majority of buyers, purchasing a motorcycle that has been professionally restored is the most practical choice. However, there’s no better feeling than rescuing a motorcycle that’s been neglected for decades and bringing it back to life with your own two hands. Of course, by “own two hands,” I mean hands that need thousands of dollars in tools, thousands of dollars in parts, and countless hours of time.

Advice: Knowing true value before you buy.
How much someone’s asking for a motorcycle isn’t the same as what it’s actually worth.
When one person lists a motorcycle for sale at a crazy high price, others follow suit. Soon, you’ll see several of the same model listed at insane prices, it’s the classic case of “monkey see, monkey do.”
Here’s how it usually goes: the first seller is a dreamer who doesn’t really want to sell but figures, “Why not list it for a crazy price? If someone pays me way more than its worth, I'll sell it. Maybe Jeff Bezos will take up motorcycle collecting and buy it” 
Of course, no one buys it, and that bike stays on the market forever.
Then Monkey See #1 comes along, spots that price, and thinks, “Whoa, my bike’s a goldmine!” So they list theirs for a similar ridiculous amount with no clue it’s totally unrealistic, months pass and they can't understand why it has not sold.
Before you know it, Monkey See #2 finds those bikes for sale, thinking their bike is suddenly a treasure, and lists it at a similar crazy price, also unaware it’s far beyond realistic.
And just like that, you’ve got a whole circus of overpriced bikes nobody’s actually buying.

The only way to get a realistic value is by finding recent sales of ones that SOLD in a verified sales or auction settings.
Kawasakis were mass produced in the tens of thousands, sometimes millions of certain models. They’re not rare like a Brough Superior. There was never a world war scrap drive that wiped out large numbers of them, like the scrap drives of WW2 where so many great classics were lost to aid in the war effort. The 1970s was not that long ago, and most of these bikes still exist, owned by regular people or in a private collection. Because they were mass produced, they remain plentiful and all models are sold in various conditions that come up for sale quite often.

Advice: If a seller refuses to provide clear photos of the frame and engine numbers, don’t buy it.
Any excuse they give for withholding this information is just nonsense.
No one can steal a motorcycle just by seeing pics of those numbers. It’s no different than parking at a gas station where anyone can see your engine number in the parking lot It’s not a social security number that should be kept secret, it’s simply an identifier that should be openly shared during a sale. Know What Genuine Engine and Frame Number Stampings Looks Like.
Sellers may advertise their bike as having matching numbers, but always take that claim with a grain of salt and see it for yourself to be certain. Knowing the difference can be thousands of dollars. Replacement frames or engines that have been re-stamped with the original numbers can look authentic to the untrained eye. However, any bike with a replaced frame or engine will have a significantly lower value. Being able to recognize a genuine number stamping is essential to protecting your investment.
It's also important to see the actual stamp, not just be told the number.
Many frames or engines have false numbers stamped on them. In cases where a motorcycle was wrecked, it was a common practice in the 1970s and ’80s to order a new frame. Since the new frame had no numbers, the shop would stamp the original frame’s number to maintain the bike’s title and registration. This was neither illegal nor intended to deceive.
However, nowadays, this practice is often done to increase value and deceive buyers.
For example, Z1s with replacement frames can often be purchased relatively cheaply. However, after a frame has been powder-coated, the thick coating can obscure the re-stamped number. This can lead to the bike being sold as an original, numbers-matching machine, artificially inflating its value.

Advice: Buy and collect what you love.
If you prefer a fully original bike, Cafe Racer, Chopper or Drag bike. The best bike is always what you like.
If you want to spend $20,000 building a drag bike, go for it.
If you’d rather pick up a barn find at a local auction and restore it back to its original glory, do it.
If you find a project on Craigslist and dream of turning it into a cafe racer, have at it.
Whether you choose to build something custom, restore it to factory original, or create something entirely unique, the important thing is that it’s yours and you love it.
The choice is yours when you do the work yourself or as a father and son hobby project.



My bikes are my bikes, please don’t ask to buy them, they are not for sale.
Now that is said, if you have a bike I want and you might sell it, I would
 be interested in buying it.
​Money I have, your bike I don't.



1973 Z1 900 Super 4
​
Frame Number Range: Z1F-00001 to Z1F-20000
Engine Number Range: Z1E 00001 to Z1E 20000
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The Z1 was produced from August 1972 to July 1973
Z1's made in August 1972 can have matching frame and engine numbers
All other Z1's have a Frame Number that is within approximately 250 of the Engine Number

Engine & frame production followed a sequential numbering system. Z1F for Frame, Z1E for Engine, 00001 to 20000

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​Z1 Engine Numbers are stamped on a 65mm by 14mm (2.5"x0.5") rectangular block on right side of engine.
Engines were painted black with polished aluminum fins and covers.

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The frame number is stamped on the left side of headstock
Frames were painted then stamped, frame numbers are stamped to bare metal not painted over.
This frame number is also printed on the white identification sticker.
This manufacturers conformity tag was required for US imports beginning the 1970 model year.
It has info including the date of manufacture in Month/Year format
This date reflects when it was made, not when it was exported, imported or sold.
The original sticker might show wear, but it will never come off unless intentionally removed.

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The Z1 colors: Orange on Brown or Yellow on Green (only available in Europe).
Official color names: Candytone Brown or Candytone Green. Kawasaki made no mention of Orange or Yellow.
​USA & Canada only received Orange on Brown, Europe had both color options.
The Z1 was made in Japan but it was never sold at dealerships in Japan. It was exclusively made for export.
Kawasaki's target market for the Z1 was the USA, receiving the vast majority of all Z1s produced.

The Z1 Speedometer & Tach have a wide space between mph & ND / x1000rpm & ND
ND is Nippon Denso the company that made them

​(The Z1A will have a close gap between mph ND / x1000rpm ND)
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Lights order NEUT FLASH BEAM OIL
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The tachometer font of the 7 changed in production of the Z1. Straight 7 was used first, later a curved 7.
The Position of the
speedometer marker at the 20 mph also changed in Z1 production
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Carburetors were Mikuni VM28SC. Carbs are marked 1470 or 147 with 2 or 3 under the 147
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Choke Lever has a black cap. The ON and arrow highlighted in red paint.
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Z1 uses 155mm long Kawasaki Tank Badges (122mm between the screws)
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Rear brake lining has NO wear indicator. All Z1A & Z1B has a wear indicator.
The last few thousand Z1's produced could have the updated casting as old stock ran out.

Those Z1s with the new casting would not have indicator arrow or useable range decal.
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No gear change pattern (1-N-2-3-4-5) embossed on the chain case cover near gear shifter.
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The last few thousand Z1 produced could have the updated casting as supply of the old cover was exhausted.
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Z1 & Z1A used a chain oiler, Z1B did not. The chain oil tank is under the left side cover.
Z1 used two style labels. Earlier being without the SAE 90.
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The plastic drain cap on the bottom of the tank changed from white to black. White being first used.
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Reservoir cap has "BRAKE FLUID" cast in metal
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Z1 Tail section document tray has 3 versions, the first label used has NOTE & engine oil capacity 3.7 qt.
This was changed December 1972, removing the word note and changing oil capacity to 4.2 qt. 
This updated label still had square corners, with the final version changing to rounded corners.
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The Z1 Frame Does NOT have a hole in the frame brace sheetmetal.
If a hole is there, the frame is a Z1A, Z1B or a replacement frame.
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The engine case has some subtle differences in the casting. For example the lower corner of the engine case.
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Just because the engine's painted black doesn't mean it's a first model Z1

The cylinder head has a few variations, the most obvious is the 903cc marking.
Z1 cylinder heads have the 903cc cast on a raised block, the Z1A Z1B and kz900 do not.
There are two versions, one having a gap between "903 and cc"
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Z1 Exhausts were welded together (muffler to header) then chromed
Z1A/Z1B were chromed then welded together, you will see a large band at the muffler connection covering the weld
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There were 2 versions of cast aluminum Lower Front Fork legs.
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Headlight fork ear brackets have a smoothed seam, the Z1A & Z1B have visible seams
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The font brake caliper mounting bolts have 3 variations.
Earliest has a small hex star inside the mounting bolt. Then came a larger star, finally no star.
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Z1 had 2 brake splitter variations.
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2 Variations of the Engine Oil label were used.
The 1st label has 3.7 quarts (3.5 litres) & 'MS'
This was revised November 1972 to 4.2 quarts (4.0 litres) and 'MS' was removed
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Only 1 label was used for chain warranty on the Z1. Label was changed late Z1A adding 3,000 miles printed on the label.
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The Petcock has 2 variations.
1st version has aluminum outlets for the fuel lines, 2nd version was brass.
​The lever was also modified to add a o-ring to stop potential leakage.
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Only the Z1 has a throttle friction screw
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4 versions of the owners manual exist, with slight variations.
​August 1972, November 1972, March 1973 and June 1973
The first edition manual printed August 1972, has a 3D font for "Z1" and owner's manual is printed in smaller lettering.
Other countries had manuals printed in their language such as Italian, French & German
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Some March and all June 1973 printings are slightly smaller in size.
Very early 1974 Z1A models were given the June 1973 Z1 owners manual.
Part number 99997-800


Z1's have 32" wide handlebars with a 5" rise and 7" pullback.
On the right side of the frame, there is a welded bracket to add an adjustable steering damper.
The frame has pre-made holes for adding an optional engine oil cooler. Riders who lived in hotter climates or areas with heavy city traffic could opt for this add-on to prevent overheating of the air cooled engine.
Rims have 40 spokes.
The original 12 volt battery was a Yuasa 12N

Original tires were Dunlop Gold Seal, Front 19" F6 B / Rear 18" K87 MARK II M

The Z1 was sold worldwide, but some countries were excluded. Surprisingly one of those countries was Japan.
Various countries had different regulations for motorcycle manufactures to comply with.
Slight variations exist from country to country since Kawasaki had to conform to specific regulations.
European models featured a seat strap for a passenger, Long rear fender, km/h speedo, fixed foot pegs, reflectors were not required and not used. Frames for Germany and Sweden have steering locks welded on the left side of the headstock. Australia and Germany used a Metal riveted tag on the frame instead of the white sticker used for US models.
Some countries such as Italy has a (*) added to the frame number.
​

The factory produced 4,846 Z1's August 1972 to the end of December 1972.
January 1973 thru July 1973 produced the remaining 15,000 Z1's.

The 1974 Z1A was also made in July of 1973, which can cause people to mistakenly believe they have a 1973 Z1.
Some people will falsely assume they have a 1973 Z1 
because the identification tag shows a 1973 production date.
If the frame or engine number is above 20,000, (higher then Z1F-20000) its not a 1973 Z1. 
In fact, Kawasaki made more 1974 Z1A models in 1973 than they made 1973 Z1 models!

Z1 Specs: 903cc Engine, 82hp. Top speed over 125mph. 1/4 mile: 12 seconds.
Weight: 506 pounds (no oil or gas)

If you don't see a white sticker on your frame headstock... You probably have a replacement frame.
Replacement frames do not have a white Identification sticker. MADE IN JAPAN is visibly stamped in the frame.
Remove the gas tank, you might find a replacement part number tag on the center frame tube, only found on replacements.

There are a few slight variations of replacement frames that were available.
One version has KHI DMG13235 0M Stamped in the headstock (this is NOT a frame number).

​Faint impressions, crooked numbers, variations in font and size, are all clear signs of a replacement frame.
​A replacement frame or engine will significantly lower the value of any Z1.

1974 Z1A info w/pics
1975 Z1B INFO W/PICS
SELL YOUR Z1

​​If you have an estate to liquidate or non Kawasaki motorcycles here are websites that might be able to help you. https://www.weekendestatesales.com/  https://www.wantedoldmotorcycles.com/

For the best Kawasaki reference guides, click below:

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  • Home
  • Kawasaki Z1 900 Info
  • VIN Identification
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  • Kawasaki H1 500
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  • How the Z1 Was Made
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  • Kawasaki Z1 900 value guide
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  • 1972 1973 S2 350
  • Z1 Buyers Guide
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  • KZ1000 Z1R