Year: 1978
Make: Kawasaki
Model: B3
VIN: KZ750B-25701 <-> 033033
Engine: KZ750BE025701 <-> 033074
Colors: Luminous Dark Green, Luminous Dark Red

Characteristics that distinguish the ’78 model years from the ’77:  Color, pinstripe layout/design (4 pinstripes; 3 green and one gold, merging at the top rear of tank, hidden behind seat front), front brake caliper re-located from the front of the fork leg to behind, new angular front master cylinder, modern stator/generator type (3-phase dynamo changed to single-phase in ’78), needle bearings in swingarm (instead of bushings), combination regulator/rectifier (changed from previously separate units), slight design tweaks in the output shaft assembly, recommended fork oil level, and there is some uncertainty about the recommended spark plug (B6ES/B8ES) between model years as dictated in the Kawasaki Service Manual.

Other model characteristics can be found in the Kawasaki Service Manual.

Here are some pictures to illustrate some of the important noteworthy model identifiers…

I believe this pic below was originally in a magazine review (not sure which):

This is a near-new specimen that shows the green color, the new '78 front master cylinder, the U.S. seat, U.S. rear fender, and U.S. turn signal position

This pic below credited to Garret of KawasakiMotorcycle Dot Org:

This pic shows how the '78 tank pinstripes disappear behind the front of the seat; of course the bike has a removed rear fender and replacement exhaust, but you also clearly see the U.S. - style seat, handlebars, and rear turn-signal placement

I believe this pic below comes from Kawasaki, perhaps from a manual or bulletin:

This pic shows the Euro-style seat strap, longer rear fender/guard, lower handlebars, and rear-most turn signal position; as well as a glimpse at the rear-mounted front caliper

But first, a few points:

• I know many people like clear fuel lines because you can see through them for troubleshooting fuel flow;  I even used to like them for the same reason.  But now I never use them because over time they get hard and brittle, and easily loose their seal when jostled, sometimes at the side of the road, sometimes just while riding.  Even if you take the extra insurance step to use mini clamps, the seal can fail in time.  On the other hand, if you use a reputable brand rubber fuel line you will not have these problems, and you won’t need clamps.
• I change my fuel lines and filters every year when I return the bikes to use for the riding season.  But even if I lived in a year-round riding climate, I’d still change them yearly.  It only costs about $10 to replace it all, and you don’t have to worry about clogged filters, rotting lines, etc.
• Never use paper-element fuel filters.  It’s not a lawn mower.
• Plastic inline fuel filters get softened by fuel over time, and can bend to the point of restricting fuel flow if you’re not careful.  So be careful.

Supplies list:

• 1 early model KZ750 Twin
• 1 package of 1/4″ x 24″ fuel line (Good Year, Prestone, or whatever is at your local auto parts store)
• 2 inline 1/4″ brass-element mini fuel filters (I get them from z1Enterprises.com whenever I’m ordering something else, but you can probably get them at any bike shop)

When the KZ750 was designed, apparently the engineers never thought we’d have to worry about fine rust particles in the tank or inline fuel filters to compensate.  Silly engineers.  As a result, if you run without inline filters, installing fuel lines is an easy, intuitive breeze.

However, since this is the real world, most of us do have to worry about rust, and we do have to use inline filters.  And because of this, we have to do crazy, creative things in order to have room to accommodate the filters… and not cause them to bend and shut down fuel flow as they soften from extended contact with fuel… or melt from contact with the back of the engine.

And this is why I’ve written this post;  My goal was to find the best way to run the best fuel lines with the best fuel filters.  Oh, and for me, “best” means “best possible at the least reasonable expense”. 

So we start with my garage plan chicken-scratch drawing on the back of a dirty envelope to help convey my design layout:

Pathetic Diagram of Petcock, Fuel Lines, Filters, Carbs

So, we start with one package of reasonable brand fuel line.  I’ve always used Good Year line in the past, but this time AutoZone had Prestone.  Whatever, it’s 24 inches of 1/4 inch inner-diameter standard fuel line.

Package of Reputable Brand 1/4" x 24" Fuel Line

As the design drawing above indicates, cut the line into four pieces as follows: 4″, 4.5″, 5″, and 10.5″ (or whatever is left).

Filters and Fuel Lines, Cut To Size

Assemble the parts so that the natural curves in the hose works in your favor, so that when assembled, the filter will be stressed as little as possible.  I’m not sure if you can tell from the pic, but the curves are opposite.  Here is the assembly order:

Left: Petcock -> 10.5″ hose -> filter -> 4″ hose -> Left Carb

Right: Petcock -> 4.5″ hose -> filter -> 5″ hose -> Right Carb

Assembled Fuel Lines And Filters

Assembly Step 1:  Connect the right line to the right carb.  I hope you have small hands, it’s tight in there.  You may have noticed in the pics that I have the tank sitting up on a wooden block for space.

Step1- Right Line To Right Carb

Assembly Step 2:  Complete the right line connection to the right output of the petcock.

Step2 - Right Line To Petcock

Assembly Step 3:  Now feed the left side line assembly in from the right side, around the throttle cables and connect.

Step3 - Left Line To Petcock

Assembly Step 4:  Finally, bring the line around and behind the other right side line, to connect to the left carb.

Step4 - Left Line To Left Carb

Here’s a finished view.  Note that the filters are spaced offset from each other, they are not bent or stressed, and the lines and filters are not touching the engine.  And hey, don’t hassle me about how dirty the engine/carbs are, or that there are old hornets nests that I’ve never cleaned out…  It’s a working man’s bike and that’s how I like it to look… 

Final View

One additional caveat though…  If you use the original stock ’76 – ’78 side covers, you will have to cut away a bit of the cover to accommodate the fuel line running where it was not intended to be.  But if you do it with a nice, smooth arc, it doesn’t look out of place.

Side Cover Cut-Away

I hope that helps!

I needed replacement intake air ducts, because I had one good intake duct and one off of something else.  As I’m sure the rest of you 750 people know, the ducts are very hard to come by.  Frankly, I wasn’t all that pleased with the design anyway, so I stopped hunting for one and came up with my own.

Moog mod, side view, on bike

Here’s what I used:  Rack and pinion bellows for a Prizm.  You can buy them right online from O’Reilly….

MOOG – R/P BELLOWS (93-83 LEXUS/TOYOTA)
Item No: K9321
$26.99 per Box (at this writing)

Moog R/P Bellows

Bought two new ones and cut them to fit.  Works great.  Has some give, so it will handle the vibration.  Much easier to connect to the carbs, and seals better than the originals I think, too.  I haven’t put the carb clamps on yet because I don’t have any.  I’m working on that next but it’s such a nice snug fit I almost don’t think it’s necessary.  It’s automotive grade rubber so it should be okay with the heat.

Did all the work on it while the air box was still in the frame too which was no small feat I might add.  Still retained all the original components (except the ducts).

Here’s a shot of the business end.

Moog mod, inside airbox view

Here’s a shot showing the bellows are actually sandwiched in between the clamps.  The seal is impervious to water.  All the air must pass through the air box opening and the filter.

Moog mod, bellows-clamp view

Note from Biquetoast:  Please note that I have not done this/these mod(s) myself, so I cannot validate any of the claims here, nor do I know the models for which this will work.  Although if you’re a 750 twin rider like me and AtLarge, you will likely face the need to find replacements like this someday too.  So if you ever try this, please let me know and I will update this page if I ever do this as well.  Good luck!!

The O-Ring(s)

Unlike *normal* motorcycles, the KZ750 Twin requires a crazy figure-8-shaped o-ring for the oil chamber cover.  The hands-down best thing for this is to get an N.O.S. o-ring for this, since nothing else fits as well.  But in a way, you have and alternative, giving you 2 main options for replacing the o-ring:

1. Kawasaki o-ring Part # 92055-084, which I’ve seen listed for anywhere between $10-$20 in various places around the ‘Net
2. The o-ring included in Fram Filter CH6014 (see below)

The Filter(s)

I have always read (and you might have too) about quality challenges in certain manufacturer’s oil filters.  But I’m not going to spend big bucks for expensive filters either.  So, I have decided to mitigate any concerns, and regularly alternate oil filters between each change.

I’m sure there are other filters than the ones I list below, but I’ve arrived at a certain pattern of use over the years, and for better or worse, here it is…  For me, there are 3 basic options:

1. Fram CH6013 – $7.28 – This is the filter that is listed for the KZ750 Twin on some parts sites.  It does fit.  It does work.  It includes 2 o-rings: an o-ring for the oil bolt that you *can* use, and a large round o-ring that you can fling at your buddy, or toss right in the garbage.  It does *not* include the figure-8-shaped o-ring.  I typically do not buy this model.
2. Fram CH6014 – $6.95 – Same filter as the CH6013, and the same small o-ring for the oil bolt, but this one *does* contain what I would call an “attempt” at a figure-8-shaped o-ring that you can actually attempt to use.  Being frank here, you can make it work, but it is not easy, because it is not perfectly shaped.  But you can get it in place and get it sealed with a little patience.  And it may just be the last hope to find the figure-8-shaped o-ring when I have bought up all the N.O.S. ones from eBay…  Did I just write that…?  I typically buy these and alternate them with the Emgo ones below…
3. Emgo 10-24400 – $3.80 – No o-rings.  And you’ll like it.  I typically buy these and alternate them with the CH6014 above.

I have bought these in the past at various places, including the links I provide above, as well as some of the places I list on my “Misc. Vendors” page.  Then there’s eBay, of course…

By the way, I’m not affiliated with any of the links provided… and make no promises regarding them… and prices were valid at the time of this post.

Good luck!

Year: 1977
Make: Kawasaki
Model: B2
VIN: KZ750B-016101 <-> KZ750B-025629
Engine: KZ750BE016101 <-> KZ750BE025652
Colors: Diamond Navy Blue, Diamond Brown

Characteristics that distinguish this model year from the ’76: Common, indented right sidecover (changed from non-indented in mid-’76 model year, and would remain indented for the rest of the “B” model run), starter lockout switch, color, and the ’76 tank pinstripe is rounded at rear, whereas on the ’77 the pinstripe comes to a sharp point at the tank side rear.

Characteristics that distinguish the ’76 / ’77 model years from the ’78 / ’79: Round front master cylinder, front brake caliper mounted in front of the fork leg (mounted behind the leg in ’78), 3-phase dynamo (changed to single-phase in ’78), separate regulator/rectifier units (changed to combo in ’78), and bushings (changed to needle bearings in ’78) in the swing arm. In ’78 there were also slight design tweaks in the output shaft assembly, recommended fork oil level, and there is some uncertainty about the recommended spark plug (B6ES/B8ES) between model years.

Other model characteristics can be found in the Kawasaki Service Manual.

Thanks for KTOF member Loic, here are some great images from a French brochure for the European version of the ’77 B2. Note that the only real obvious differences are the longer rear fender, the rear turn signals moved to the rearmost position, metric “clocks”, the “z750″ naming, the seat strap, and some lighting tweaks for local standards. The best part is that you get a real good look at the stock colors and equipment.

Click on the picture to see the full size image. C’mon, you know you want to….

Page 1 - Here you can see the Euro-style seat strap and blue color

Page 2 - The red color, and a good look at the longer Euro-style rear fender/guard

Page 3 - Note the '76/'77 style front-mounted front caliper

Page 4 - One other important Euro-style attribute is the high, rear-mounted rear turn signals

Page 5 - Here you get a good look k at the Euro-style lighting controls

Page 6 - It's a beaut, isn't it?

Year:  1976
Make:  Kawasaki
Model:  B1
VIN:  KZ750B-000001  <->  KZ750B-014947
Engine: KZ750BE000001 <-> KZ750BE015032
Colors:  Diamond Red

Characteristics that distinguish this model year from the ’77:  Early non-indented right sidecover (changed to indented in mid-’76 model year), no starter lockout switch, color, and the ’76 tank pinstripe is rounded at rear, where the ’77 comes to a point

Characteristics that distinguish the ’76 / ’77 model years from the ’78 / ’79:   Round front master cylinder, front brake caliper mounted in front of the fork leg (mounted behind the leg in ’78), 3-phase dynamo (changed to single-phase in ’78), separate regulator/rectifier units (changed to combo in ’78), and bushings (changed to needle bearings in ’78) in the swing arm.  In ’78 there were also slight design tweaks in the output shaft assembly,  recommended fork oil level, and there is some uncertainty about the recommended spark plug (B6ES/B8ES) between model years.

Other model characteristics can be found in the Kawasaki Service Manual.

This picture below (owner unknown) features the earliest version of the B1, with the original un-scalloped sidecover.  The bike appears to be fairly true to stock except for paint/stripes, missing grab rail, and an exhaust from a later model (perhaps a G1):

Early B1 with first version of sidecover

This B1 below (owner unknown) has the later ’76 sidecover, with the carved-out spot for the kick start lever at rest.  It appears fairly stock except for a MAC exhaust (with stock headers and cross-over),  and a re-upholstered (and over-stuffed) seat:

Later B1 with scalloped sidecover and stock paint

This B1 below is a U.K. model (owned by “Peter” from many forums, R.I.P.), featured here for the subtle U.K.-specific differences such as a mid-seat seat strap, the “z750″ badge for the everywhere-but-U.S. model name, and rearward-mounted rear turn signals.  Oh, and note the early non-indented sidecover again.  Of course, it is re-painted, has custom-made exhaust (stainless steel, if I remember correctly), case guards, chrome gauge/clocks covers, and stainless brake lines:

U.K. Model B1

NOTE: If you know (or are) the owners of the bikes above, please let me know so I can credit you correctly.

On one 750, I had a complete stock exhaust system, with rotted out ends.  This bike pulled like a freight train; waaaaaaay better than the other 750 that was otherwise identical except for a non-crossover system with Jardine Classics (that breathe very well).

So when I replaced the rotted stock system, I made sure to retain the stock headers and crossover, but replace only the rotted mufflers.  Unfortunately, I didn’t take pictures or notes of that work on that bike.  However, I finally got sick of the power difference between the two bikes, and decided to add the crossover to the other bike as well…  And *this* time, I got pics…  So here we go…

First, the parts.  Besides a complete stock exhaust system to be cut up, you need a few things:

Replacement mufflers…  I chose some MAC tapers, that I got from Dennis Kirk “Scratch and Dent” for chump change:

Optionally, fiber wrap (because in my case, the pipes are cosmetically challenged):And the stainless steel straps to hold the wrap in place:And the high-temp paint to 1.) paint the pipes after sanding and before wrapping and, 2.) paint the wrap after it dries (from wetting during application):And of course, muffler clamps (again, from Dennis Kirk)…  you don’t want your mufflers to fall off do you? Or leak…:First, you have to cut the stock mufflers off the stock headers.  Inside the pipes, underneath the chrome and the outer pipe of the double-wall pipe, there is a gap between where the inner-wall of the header pipe and the baffle in the muffler almost meet up.  This is where you cut.Looking inside the now-cut-off muffler, you can see how close I cut next to the baffle pipe, just catching the edge of it:Here’s the whole carcass:But now here’s where you approach the main catch of this whole thing.  At this point, you have to clean up the left-over bits of the muffler that are still welded to the header pipe.  But, once you grind all that off, you have to keep going; because the clean pipe is actually about 1 9/16 inches.  This means that your 1 1/2 inch slip-on does not yet fit.  So, grind, grind, grind, and let me tell you; this pipe is no soft metal…  Here’s what it looks like ground down to about 1 1/2 inch:Then, if you haven’t already at this point, it’s time to optionally apply the fiber wrap.  You need to sand the pipes, paint them with the high-temp paint, let that dry, apply the wrap (wetting it along the way), let the wrap dry overnight and/or in the sun, and then paint the wrapped pipes again, this time to seal it from the elements.  Here’s a look at the wrapped, but as-yet un-painted headers:…and a close-up of the top strap in action.  Note that I started at about the place where the pipes clear the head; you don’t want to start to close to the beginning, or you can’t get the header clamp in place.  Also note that at the start of the wrap, you wrap it *under*, so the loose end is not exposed: …and here’s the other end, where you really need to fold the end of the wrap under before strapping it down… I did a sloppy job, but it won’t be visible… :Okay then!  So in summary, here’s the requisite “before” pic, with the rusty, non-crossed-over headers, and Jardine Classics:And here’s the “after”, with the picture taken right before the first ride:And Did I mention they smoke like CRAZY when you do this?  Oh yeah… make sure that when you take your first ride, you stay in motion, or you will be bathed in the rising noxious smoke of the baking paint and fiber… Anyway, here’s the “after” taken right after the first 15 minute ride, with the freshly wrapped pipes still smoking… :And a little closer view of the pipes:And another pose:And finally, once from the rear:

My Stock '78 Side Cover

It has always seemed to me that the ’80 “G” model sidecovers were a perfect “tweak” in design.  And since they are almost the same bike underneath the minor cosmetic differences, I had always hoped they sidecovers would be inter-changeable.

Thanks to a quick note of confirmation from fellow KTOF member Steell (who had also swapped his covers), I was soon regularly searching eBay for a set.  He confirmed that although they fit, they leave one mounting grommet exposed, since the old covers used 4 mount points and the ’80 type uses only 3.

So I finally got a set for like $10, removed the “750t LTD II” badges, painted them satin black, and here’s how it looks now…

'80 Cover with Exposed Mount

What to do with the exposed mount and grommet?  Install a garage door opener?  Move your ignition key there?  Mount an LED side running light?  Or do nothing to them (like I intend)?

However, I think I will probably try to find a spare set of ’78-style badges to fit there to fill the holes in the covers and finish off the look.

So, just to recap, here’s my ’78 B3 at a full view before…

'78 KZ750 With Stock Sidecovers

And here it is after replacing the stock covers with those from an ’80 “G” after…

'78 B3 With Sidecovers from an '80 G

Truly a minor cosmetic tweak, but I think it looks better!

Want *real* stopping power from the front brake on your old KZ750 B or G model?  Want double-disk performance without breaking the bank?

Fortunately, you don’t need to replace the wheel, there are provisions for the second disk on the stock wheel.  But there are a few other components you will need to add or swap out.

The stock single disk is thicker and heavier than dual disk brake rotors, so you are best off to replace your one single rotor with two from a bike with a dual-disk setup (77-80 KZ1000, maybe 78-79 KZ650 but check diameter).

So you want killer brakes on that bike?

• 77-80 KZ1000 12″ brake rotors
• 83-85 GPz750 calipers
• 95-96 GPz1100 master cylinder
• Stainless steel brake lines

It will stop you on a dime and give you change back… 
I just described the brakes on my ’79 750 twin (specifically: rotors are 79 KZ1000, calipers are 83 GPz750, master cylinder is 96 GPz1100), so I know it works.

The same calipers are used on other models, same thing with the master cylinder, I just don’t remember what models/years used them.

Speaking of budget, I thought I’d post my parts/shopping list for the upgrades as I do them.

For my first 750, I decided to try building the stainless lines myself from components, instead of buying pre-built sets.  I found a site that had a good reputation and price (mgcycle.com, a Moto-Guzzi specialist shop), and contacted them with some questions.  The proprietor was a bit surprised when I told him I do not have a ‘Guzzi, but he was kind and helpful nonetheless.

Together (over a few emails), the salesperson and I came up with this list, made up of “Earl’s Brake Line Components”:

• 8 Copper crush washers, $0.75 each = $6
• 2 #600503 30 degree adjustable banjo fitting – 2 x $16.50 = $33
• 1 #600803 30 degree non-adjustable banjo fitting – $12.25
• 1 #600703 straight non-adjustable banjo fitting – $10.50
• 3ft #6000031 clear plastic covered braided stainless steel brake line – 3 x $7.75 per foot = 23.25

….for a grand total of $85.

Believe it or not, he ended up sending me enough excess line that I have enough to probably do the rear brake… someday.  Be forewarned though, that the “Earl’s” brand is sold as individual components; meaning you cut the lines (here’s a tip, wrap it in masking tape when you go to cut with a sharp hacksaw), you assemble and crimp the ends (another tip: use some heat-shrink tubing for a professional look), and you get poked alot in the fingers by tiny little sharp stainless wires.  Okay, it’s not that bad, considering the savings…

I have since found a couple other great vendors for stainless brake lines.  For instance, z1Enterprises.com started selling pre-cut/crimped lines in various lengths (the kind that has a swivel that you screw together), so I used those on my KZ400 with great success, for even less money, believe it or not.

HEL Performance has special pre-built kits labeled/indicated as for the 750B models, and the Y models.  Though they cost a bit more than doing it your self, it looks pretty convenient.  I’d like to hear from you if you’ve used these!

Also, Spiegler sells separate kits for the front (S-KA0080, $109.95) and rear (S-KA0079, $56.95), labeled as designed for the ’76 B1.

Remember, as always, I don’t endorse any of these vendors, I’m just passing along what I have seen out there…  Anyway, I will update you all later when I get around to doing my other 750…