Just wanted to add, the KZ440LTD rear wheels are 2.5" not 3.00"
And I'd say go for the fork swap, for the stiffer front end, just don't go with too heavy of a fork either. The goal should be to make these bikes lighter, not heavier.
And toward that end, I'd say stay the heck away from the mag wheels - take KZ400 spoked hubs and lace 'em up with some affordable alloy spoke rims, Mike's XS has some great clearance items, and I like the look of the 2.5x16" even more than the 18" versions
On my kid's KZ440LOL I'm going with 3.00x16" vintage Borrani rims, these were often used on choppers etc. But I plan to use that one up front, I've got a couple of GT750J 4LS drum hubs, one for spare & tire changes etc - I've got a bunch of these rims and also a 3.5x16" Akront rim - had a "Super-Akront" in this size but lost it in a fire, along with everything else, have replaced everything, NOS belt-drives in 22:60 & 22:65, the 4LS hubs, the bikes, my CB750F is now a CB900F and I've got even better parts for it - but I still lament the loss of that Super-Akront rim it was beautiful and super ultra LIGHT.
So yeah the PLAN here is to use Maxi-Scooter tires in 110/70 & 140/70 - but the 2.50 rims from Mike's XS might just work with these same tires OR use say, 100/70 & 120-130/70 for a slightly lower load bearing range. Which would work better on a single-seat bike, lightened let's say you took the electric starter out or went with the 'S model which never had it, strip off the battery & use a battery eliminator, just use the kick-starter EVERYTHING you can do to shed weight from the bike from fiberglass fenders to a 2LS drum front hub (taken against the disc, hub, caliper, master-cylinder, lines, all put together not to mention if you were formerly using cast-mag wheels which are heavy as shit - and yeah that single puck single disc system on the KZ400/KZ440 was a crap brake anyhow - so take THAT against using say, the T500 Titan Suzuki drum or a CB77 (same as CB450 but 36-spoke to suit the alloy rims from Mike's XS, which the rear wheels suit a large drum and I think they've got front rims drilled for the XS1 drum version anyway....) AND if you keep that drum-brake in top-notch form, polish the fucker drill it for cooling put some air scoops on it take some fucking PRIDE in the thing and rebuild it a couple times per season and I'd bet it would kick ASS on the stock disc system and more to the point you could save a shit-load of weight. Just a suggestion that would help towards using 2.50" rims. Either way, he's ALSO got some good 18" rims you could use 2.15" front and 2.50" rear and use a narrower tire than absolute max, use stock KZ twin tires but with a straighter side-wall if nothing else THAT would help things even if the weight stays the same....
Some good light-weight rims should go a loooong way toward making the bike handle better, accelerate a lil' faster. And check 'em out at Mike's XS his prices blew me away, especially after spending so much on "period correct" vintage performance rims etc.
The thing about using drum brakes is IF you decide to go that route, just go with as powerful a brake as you can get. Consider if you will, the T500 is 80% that of the 4LS GT hub (though the GT hub with shoes made from modified T500 shoes should get a smidge more contact area) - I'm just saying, IF you're gonna build a new wheel whether you go with the OEM chrome rims or not, for the trouble of building it alone never mind the cost of spokes & rims - go with the bigger drum 'cause it's redundant to stick with the smaller 160mm or 180mm stuff when there are great 200mm drums available for cheap. You could use a smaller drum in the rear to make up for the weight, just so long as the rear drum is enough to use for ONE panic stop! Once you're riding like a madman anyway, you'll use your rear brake a lot less.
The thing about the 4LS drums, is unlike the later twin-disc systems which were made to add more power to the brake, the double-sided DRUMS were made to stabilize the front suspension by balancing the forces onto both fork legs, so as to avoid dumping a whole bunch of stiction into one leg and not the other. It seems that a good way to obviate this need would be a heavy-duty fork brace. And more to the point, a better fork. Even if you stayed with the 33mm tubes you should look at WHICH of the 33mm, 'cause I heard somewhere that certain of the KZ 33mm don't even have bushings in 'em. Or perhaps it was earlier 33mm? Either way, it seems like a 35 or 36mm would make much more sense.
I'm using the CB900F 39mm, just 'cause I had a spare one laying around. I'd try out a 37mm if it would shave off much weight. I weighed a burned out (in a fire) 37mm and it seemed close enough to the same weight, so I've abandoned the search for a 37mm.
But yeah, a SLIGHTLY better fork, but one still light enough not to turn the bike into a slug. A Fork-brace but not just a cheap PLASTIC one. A good large-diameter 2LS drum, an alloy rim preferably new production with the ridge for tubeless rims, & strip the pounds off the bike where you can. Date a chick who rides her OWN bike, it's counterintuitive but this is far more intimate than wrapping her around you like a knap-sack!
I think the KZ440 has some untapped potential. Lard knows, if I had my druthers I'd go with a Honda 'cause I'm a DOHC Honda guy - it would be cool to build a CB500T for the kid to go along with the "CB900K0 Bol Bomber" I'm building for myself. But Kawasaki was VERY forward thinking in using a belt-drive on these bikes. Albeit the belts of the day weren't as strong as we have NOW, where current belts are as strong as a chain in like widths (Gates Industries' "Poly-Chain GT-Carbon") - but they STILL save drive-line mass, un-sprung weight on the rear hub, and transmit a greater percentage of crank horse-power to the rear wheel. If shaft-drive is supposed to be the least efficient, dumping 15-20% in driveline losses, and a chain is slightly better at 10% losses, well a BELT is that much MORE effiecient, something like 5% losses to the drive-line. And a smoother power delivery meaning less need for a huge cush-drive in the rear hub hence even MORE savings in un-sprung mass etc.
That was brilliant stuff. Other than Kawasaki, WHO was doing this? It behooves one to show what all this could mean, especially when the bikes are no longer encumbered by all of the dead weight boat-anchor type of shit the styling department put on the bikes. Like the mag wheels.
Think about it - Sure an alloy cast mag wheel can weigh a little better than a steel wheel, and when it's got it's disc & caliper off the rim I'm sure it's even lighter than a new drum hub with steel rim etc. The key word being NEW drum, 'cause using a spun-out drum means a thinner liner, and though you'd have to shave your shoes down to suit it, this could glean performance dividends. Seriously though - compare a wire-spoke rim with an ALLOY rim on it, and even when you're at the same mass, the wire spoked wheel has more of it's mass toward the center of the wheel, while the cast mag wheel carries more in the circumference. This is because an alloy WIRE wheel is extruded and butt-welded, engineered to be supported every 1/36th or 1/40th, while the mag wheels are cast very thick to span across unsupported sections. On the KZ these spans are only 1/7th but they're still cast just as thick as on a wheel with only 5 or even 3 spokes.
It seems like Kawasaki was gravely concerned with how their wheels would perform in an IMPACT, as they're sooo much more over-built than even those rims built by the other manufacturers. Yeah, I realize they picked up the designs from Morris Mag who supplied rims for their first mag wheel models (take a look at Jim Goose's bike in "Mad Max" - in those high speed sequences you can clearly see his rear wheel has a bolt-up cush-drive, which was integrated into the casting on later Kawasaki-built rims!) But they're NOT "Mag" as in "Magnesium". More like Mag-NUM ha-ha.
Another big fail was the spoked rims Kawasaki put on the KZ-CSR models. My original "cost saver" plan for this 16" wheel set was to use KZ1000CSR & KZ650CSR rear rims - I had dug up specs claiming a 3.5" rear on the 1000cc - they both turned out to be 3.00, and the 1000cc rear hub was so damn heavy it'd be better to use pretty much anything else, so I didn't even keep THAT for my CB750F project - I was thinking the 48-spokes per wheel could be adapted to drilling 12 more holes in a 36-hole hub, drill out the rim for larger spokes etc - I dunno WHAT I was thinking, but I hadn't hit on what other alloy rims were out there in 16" yet. ANYHOW - the big fail wasn't the 48 spokes themselves, it could make for a very strong rear wheel, it could make for a 6x6 spoke lacing pattern which is super cool - no it was what they did to ACCOMODATE the higher spoke count - due to the lesser gap in BETWEEN the spoke holes, in order to avoid more frequent cracking between spokes (as is common on off-road rims in between the valve hole & adjacent spokes - & on the 'CSR what with the tiny 16" rim the spaces were equivalent to just that same issue, PLUS they also had their own valve-hole along the center-line ... as opposed to a 45-degree off-set valve which was common on 16" rims) to avoid cracks they had to build the rims really really THICK, and the weight goes up in concert with this. As such, though you might THINK it's an improvement to stick the alloy 'CSR rims on your bike, they'd probably perform no better than a comparable chromed-steel firestone 3.00x16" Harley rim which were the rim of choice for cheap chopper conversion in the '70s, ie they were heavy assed garbage! It's a pity. I'm sure the THINKING was for long-term indestructability, or more to the point impact resistance - but there are many many KZ1000's out there sporting 40-spoke lightweight alloy rims whether Borrani or Akront or Super-Akront, and those wheels put up with all sorts of road-racing abuses, DRAG racing abuses, even off-road abuses. So why overbuild the shit out of 'em?
Now, I'd advocate skinny 18" or wider 16" for the KZ305/KZ400/KZ440 or other comparable twins - maybe some vintage Borrani 2.15x16" for pinched bias-ply balloon tires, or even 2.50x17" for some '90s era rubber from a 125cc road-racer etc there were very interesting 2.15x17" & 2.50x17" rims in that era sporting lower profile 17" Bias tires that were only as wide as say 120 130 max - THAT might be an interesting permutation for a middle-weight twin with performance less than a Honda VTR250 etc - I suppose a lot of them '90s racers had wider rims than that but there were a few with "skinny" 16"/17" rims which would be damned interesting to replicate with odd-ball '60s-'70s Borrani rims - I'm at a loss for what all else one could do with a 2.15x16/2.15x17" rims other than I've seen some old BMW's fitted with 'em, vintage Harley clincher rims were 2.15x16" etc - but several '80s Sport-bikes like VF750F used a 2.15x16" front wheel, & if that tire could match to a skinny 2.50x16" on the KZ without mismatching the rubber, it would certainly be interesting! It's important to note, yeah those same bikes often switched to 2.50" width within a year or two, even THAT was pinched compared to tire manufacturers' recommended rim widths, and so it's just one of MANY oem tire/rim combos which are out of spec! For instance, the same rubber I'm going with is a common size, upgraded for better longevity, frequently used on the Buell Blast 500cc single, but it's pinched 'em onto 2.50x16" & 2.75x16" rims - surely then the same degree of "pinch" could be applied to other tires in the same series, such that if the 110/70 & 140/70 combo fits 2.50 & 2.75, ergo 100/70 & 130/70 should squeeze onto 2.15 & 2.50"x16" rims from Mike's XS, or equivalent vintage Borrani/Akront etc. Still, it's the odd-ball "skinny" 17" sizes which elude me, as I know there were 130/80 tires for CB750A/CB750K8, GL1000, CB750KZ & CB1100F rear 2.50x17" rims, I don't know of many other tires in the middle ranges between the 1.20x17"/1.40x17" rims from Honda CUB underbone models, there were some CZ Puch & MZs that used 1.60x17" and so too there were some early Honda CB72 & CA72 models which used the same or even 1.60x16" rims - none of these are suitable for KZ400/KZ440 - but then again I was never all that much into the late-'80s early-'90s track-bikes, & I know there were some wheels in the range of 2.15-2.50" in both 16" & 17", even some rather odd 3.00 & 3.50" widths of 15" rims used on stuff like the Honda 250 Rebel, for which there are these modern Maxi-Scooter radial & bias tires made in some weird diameters such as 15", 14", & even 12" - meanwhile several off-road mini-bikes used 12" & 14" rims albeit very skinny in comparison. And here too there are some very odd spoke counts incompatible with hubs you'd want on a KZ twin. But STILL - there are some odd-ball rim & tire combinations which I haven't seen done, albeit most of 'em would only be suitable for a scooter in any case.... Looking at the range of wheel sizes people use on '70s-'80s Superbikes, there's something to be said for a visual proportion between the size of bike & engine, & it's wheels - I'm not suggesting the same long spindly forks with little wheels at the ends, so perhaps I'm suggesting something be given up in cornering clearance. But then, my kid said she wanted a bigger SCOOTER, & this is why I went in this direction with the KZ, I fully expect the end product to be more scooter-esque than mirroring the lines of a classic '60s racing twin.... And I AM leaning towards a side-car. A leaning side-car that is. Heck, if you get into the square-profile side-car tires, there's a lot of stuff made for utility trailers which you can find at the likes of Crappy-Tire (Canadian Tire for the uninitiated), Princess Auto, etc - odd-ball sizes which I can only speculate would make some awesome wire-spoke wheels if only the rims could be found. For a long time, I ogled a single pair of Borrani wire-spoke 3.00x12" rims on eBay, presumably made for some antique car, they had a weird spoke-count and obviously intended for a conical Borrani auto hub, but DAMN were they cool, I could just SEE 'em on a vintage side-car! Mmmmm......
If you want the cheapest rear rims out there for a KZ1000 or thereabouts, I found some 4.25x17" & 5.00x17" 40-hole alloy rims, albeit drilled for Harley, on eBay for $39.99 - the guy probably still has some of 'em. With a re-drill job for larger diameter spoke nipples, and custom spokes to suit - then a 36-hole front hub from GT750/GT550 wrapped up in a slightly more expensive 3.00-3.50x17" Supermoto front rim, or more to the point a 2.50x18" front rim which are cheaper (I scored some Harley unmarked Borrani used rims in 2.50x18" for $50 with delivery, & by that I mean delivered to Canada - Harley rear hubs are approximately the size of KZ front hubs & with the same 40-spoke count - this would net a rim set comparable to the new Triumph Bonnie etc - but ME I'm not into that type of thing on a classic Superbike & I've bought a set of 2.50x18 Harley + 3.5x18" Super-Akront AND a set of 3.00x18" new production clone knock-off flanged non-drop-center, ie looks like an old WM3 but much wider - and a 4.25x18" Akront rear - two sets one "period correct" & one for smallest width of Radials in 18" for correct view from the side, stance etc.) There are TONS of good rims out there for bigger bikes!
But the KZ with it's stock 1.60x18" front and 1.85x18" rear, there are TONS of old rims in these sizes that nobody's bought. Many not even drilled yet. Meanwhile 2.15x18" & 2.50x18" are being reproduced for decent prices, the price going up with the width. One ideal outcome being that the new production in 1.85" (probably the smallest they even make) & 2.15" would not only be the cheapest, but new ones would have the tire bead retention ridge & hence would be suitable for a silicone tubeless fix, AND they'd run stock ie lightweight tire with a straighter side-wall for better line-tracking etc - THESE would be the lightest wheels you could put on the bike. (Unless my 16" wheels squash that whole concept with lesser rolling inertia?)
Seriously though, even WITH stainless steel spoke nipples (would a KZ twin get away with chromed-brass nipples? Just a thought!) AND the steel or stainless spokes themselves, there isn't nearly as much weight in the perimeter. It's concentrated in the hub, where it produces less rolling inertia. Which is a GOOD thing. To paraphrase Martha Stewart.
Yeah, I do realize I'm talking about spending more money than a lot of folks are comfortable with. And to THAT I just say ... suck it up and stop smoking, stop going to the bar, eat a little more ramen noodles, or even move back in with your parents if you have to. 'Cause NONE of that shit is gonna make you as happy as a good set of wheels & tires on your bike!
Trust me - that girl you're dating who would dump your ass if you moved back into your parents' basement to save up for wheels? Yeah - get rid of her NOW, before she does any more damage than necessary. Find yourself a chick who wants to build her OWN set of cool wheels, who doesn't need to spend a shit-load of both your paychecks on garbage knick-knacks from IKEA just to express her "nesting instinct" - trust me, you might get blue-balls but you'll be happier in the long run.
And let's assume that I AM talking to a bunch of 20-somthings here. Yeah - get rid of your fucking VIDIOT GAMES while you're at it! Get rid of your TV at the same time, then you'll have more money AND time to work on the bike. Nix the cellular telephone. Me I like an "old fashioned" rotary 'phone. Hipster chicks might even dig that so much that you'll be getting laid again. But if they don't like your dumpster sofa or your bike sitting in pride of place in the center of your living-room, heck even if she wants to bring a fucking kitty-cat into the place which would piss all over your new wheels? GET RID OF HER. There are better women out there. And that thing she does? Yeah ANYBODY can do that. It's nothing special. Don't be so easily manipulated.
Cough. Yeah - as I say, it IS possible to stick some nice rims on your bike. It IS possible to have a couple of bikes and to treat 'em like never ending money pits. It all depends on what all else you're willing to give up toward that end. This would be a good way to show that young lady that you DO have "commitment" - just don't risk having yourself committed to an ASYLUM to prove it to her, & make your commitment to something WORTHWILE. Such as a bike, instead of some vapid young twit (aka twet, twot, twut, twyt or ____) who screws around with YOUR life, YOUR psyche - simple because she doesn't know what to do with her OWN self. Turn that argument around on it's ass - say something like "Well I don't see YOU building an awesome café racer Missy! What are YOU building?" - give her a chance to respond and say "Yeah but I don't give a SHIT about interior decorating! All of that crap just comes out of a catalogue anyhow! How about you do something CREATIVE, and make your knick-knacks with shit people throw out? Like this lamp over here that I made - check it out, one empty Chianti bottle one candle, voila!" - lather rinse repeat. If she doesn't see reason, she's not a keeper.
Or how about your asshole friends who spend all their money at the pub, drinking beer & smoking cigarettes just to look like they're DOING something, on the off chance of hooking up with a female? Worse still, the ones who drink beer that costs four times as much down at the nudie bar. Give 'em a home brewing kit, a bag of candy, and directions to the local high school. Whatever you do, DON'T get sucked into their activities. This is NOT an effective use of your time nor your brain cell destruction quota. Not when there's carburetor-cleaner to be inhaled. Alcohol consumption is the antithesis of riding a motorcycle, and not only 'cause never the twain shall meet. Riding a bike is about jacking up the flow of your own endogenous opioids. Whereas drinking crappy pre-packaged light beer is only a tip of the hat to the proper type of Chinaski-esque self-destruction which so many young men aspire, as manifestation of their closet homo infatuations with the likes of Ernest Hemmingway. If you feel the need to "take the bull by the horns", pretend while you're holding the handlebars of your KZ. The self-destruction will inevitably follow due to inadequate protective gear, you won't NEED to do it deliberately nor ineffectually. What's more, it's good for the EARTH, vis-à-vis global warming, urban traffic congestion, smog, what have you. Never MIND that my kid's Yaris gets better fuel economy than my CB900F - the point is that we have to motivate society to put the style of classic motorcycles back into production in concert with everything that's been learned along the way of producing engines like what powers that little jelly-bean of a hatchback.
I could go on at far greater length, but suffice it to say: I feel that riding a classic mid-displacement motorcycle might just be the thing which could save us all. Even if each of us have to take several couch-potatoes under our wing, and run all of their errands for them, back & forth delivering pizzas & soda pop, electronics & other consumer goods - even if we wind up towing a wheelbarrow behind our bikes so that said couch-potatoes can move from point A to point B, it is incumbent upon us that we promote classic motorcycles & classic motorcycling until every last Hummer2 is converted into a static home for a family of one, & more to the point until major motorcycle manufacturers start building COOL bikes again.
I even see the use of over-sized drum-brakes as contributing, 'cause some day I see the same aesthetic applied to regenerative-magnetic braking for electric bikes - which don't look like plastic shit-boxes anymore - which dump this heady "futurism" for a return to the past & classic industrial design principles.
We need to get out there on light-weight classic mid-displacement twins and embarrass the SHIT out of all those sows on their hogs, ride circles around 'em, until mainstream society begins to see REAL motorcycles as a practical and enjoyable mode of transportation again, one which doesn't require that we play dress-up in order to play a part in somebody else's narrative.....
Ahem - YES. And in order to do so, one needs to put some decent wheels tires & brakes on their KZ400/KZ440, and make use of the belt-drive wherever possible.
Whaddya think, if a person were to dig through the Gates Industries catalog, would they actually FIND an applicable belt that would work with the stock pulleys? Probably. And if not, one would THINK that Gates could manufacture a belt to suit, which could be sold for less than the price of a new chain. At which point, all of those rusty pulleys on eBay for $5 a pop could take a coat of Rustoleum & test out the belt longevity. There's nothing to lose from such a proposition, & everything to gain. Yanno, the KZ twins forums should put together a plebiscite to send to Gates, "we the undersigned" being anybody who'd be willing to pay the same as a chain for a cheap belt built to the same specs as the late '70s early '80s Kawasaki tech. Even better still, if they could be built a lil' better, and you could take that same pulley set and file it down to the width of a sprocket. Okay, so that's a lot of work. So be it. Gates has a catalog full of pulleys, the make collets to fit 'em on ANY splined shaft - you would think they'd start offering belts for more than just the Harley primary & secondary drives, or the Zero-S electric bikes ... & do they make Ducati timing belts? You'd think so. But yeah, when you think of how bike CHAINS come in pretty standard lengths, it's a wonder how they don't just sell pulley kits & collets for specific bikes, plus a line of chains in a standard range of tooth counts. There's a reasonable set of numbers - for instance I've never heard of a bike chain with say ... only 22 links on it. Maybe some old fashioned primary drive from a 1900's Velocette? But yeah, it's only reasonable to assume the range of belts would hover around 50, maybe 70 different belts - they shouldn't have to make 'em in 525 & 530 & 630 etc. The point being, once the belt is made to a certain tooth count it can be cut to any WIDTH that's suitable. And then you'd have ratios - It's reasonable to assume you could come to within two decimal points of ANY given drive ratio AND staying within the given range of length (especially given the far lesser range of adjustment required over the life of a belt) by making front pulleys in a small range of tooth counts and rear pulleys in the same.
Seriously - if you look at what all they make for the industrial power transmission engineering set, it would be NOTHING for these guys to take over the entire motorcycle final-drive industry, & drive the chain people straight out of the biz. & given the fact that it's an improvement on existing rear-wheel horsepower, you'd think that ALL bike people would be clamouring for these new belt systems.
Still - even if that doesn't take place. The Kawasaki belts were taken from a given industrial design. It is VERY likely that belts are still made to that existing specification, even if it's just to support whatever application those belts were originally built for. It would be ridiculous to assume the belt people would court the KZ twin belt market - but I'm sure that if nothing else they've got a box in a warehouse full of NOS ... I dunno, agricultural tractor/combine belts. Or perhaps it was for some institutional size dough mixer for commercial bakeries or potato peelers for galley use on some naval vessel? What else? A ventilation fan for old pig barns? Alternators & water pumps for some obscure Fugly little '70s sub-compact car? (I LOVE cars like that!) Somewhere there's a stack of these belts. And you'd better bet most of those eBay pulleys were only ever run with their first belt. The pulleys were supposed to last for three or four belts! Now, ME I got lucky - yeah the first set I bought, I paid too much for NOS pulleys & didn't have a belt, was looking at buying a used one. But then I got "lucky", which is to say I spent the better part of last winter using an eBay search for NOS belts for KZ as my internet home-page, refreshing it over & over - you can't calculate the dollar value of that ha-ha. But then I got my belts & pulleys for as cheap as chains & sprockets. Snapped 'em up within minutes of their being posted. So yeah, I got "lucky" ha-ha.
But somebody ELSE is gonna bring us ALL some luck at some point, when they dig up WTF else these belts were used for. I have half a mind to mail one to the Gates people, see if they can identify the type. Heck - even a crapped-out USED belt would suffice for that. Though far better to measure from the NOS belt to get an accurate tooth profile.....
Seriously though, NOBODY else has this on a '70s/'80s twin. Just the KZ305/GPZ305, the KZ400/KZ440, and the KZ750 twin! Plenty of bikes switched to shaft during this time, in the hopes of building in less maintenance etc - meanwhile they sacrificed performance & efficiency, they introduced shaft-jacking - just an all around crappy trade off when compared to the belt-drive option. The only reason it didn't catch on was it had to wait for the composite materials tech to catch up, and it finally has.
Whatever else you say about the KZ twins, this was a unique technological leap-frog. As such they're every bit as "deserving" of being restored, improved, invested in - as any of their "competitors". I'm not saying they can't ALSO be treated as cheap economical transport. Or somewhere in the middle. But why cheat yourself out of that better performance?
-S.
