Need Measurements for Seat pan, CB750K0 Sand-Cast for "Duck-tail" DOHC project


Been Around the Block
Hey there people. I was hoping that somebody would have a blank seat-pan sitting around from their SOHC CB750K/CB750F project, and that they could measure it out five or six different ways, and help me out with the major variables so that I can draw up a template of my own, to build up from fibre-glas. Well, okay if I am gonna use brand names, I might as well be honest, and say "Bondo". Ha ha. I'm looking to make YET ANOTHER fibre-glas seat pan for my '82 CB750F. I made one that worked out great, pops on and off the frame like a shoe, might not even need bolts. Anyway, now I would like to do another, because it occurred to me that what I want for a seat cover is one of those replica "Duck-Tail' seat covers for the Sand-Cast. Basically, I've been working on building a DOHC "Replica/Tribute to the Sand-Cast", (Next time I wanna try it on a Black-Bird or some such, ha ha.) Something not unlike the work that Whitehouse Japan has done with their new CB1100 they call the "K10" Check it out:

And, I hasten to add, I thought of it FIRST. Ha ha. I've been on disability for the past twelve years, and I "Nod-off" on my medication for at least half of the time. So if anybody ever wonders "Where the hell is this finished bike, then?" First of all, it's mostly been discussed, and what few pics I've done, over on the forum, as much as anything 'cause of the technical help available there, not to mention the fact that it puts a bug up the butt of a lot of "Super-F" builders to see anything remotely "Cafe-esque" on "their" forum. (Not to mention, Glenn doesn't censor word one of the whole set-up, and drama queens can't rally a cause around banning somebody. I very much admire that ethos. Or, PATHOS, as the case may be.) What I CAN tell you that it's something like half done, just held up by financial crap that's finally beginning to dissipate. Well, I did take a break in the middle there to focus on raising a kid as a full time Suzy Home-maker House-Husband type what with all of the twenty girl slumber parties, baking all of the cheese-cakes and decorating Kwanzaa cookies and shit. So, yeah anyway finally the damned bike is coming together. My other seat pan has been sitting for something like ... three or four years, so the thought of doing a custom sewn vinyl cover for my seat pan was kind of a pipe dream. Now I'm embracing the notion of a pre-fab build, where I can just grab a part here, a part there, and throw the whole thing together, rather than pretending to be some kind of crafts-man. Maybe I can use the old seat underneath another plate, bolt them together with rubber in between.... Ah, it would just be easier to make a good heavy pan of the right dimensions, bent to fit the DOHC top sub-frame rails of course, and then find a way to bolt that to the frame with rubber bumpers. Going for the slim-line low "Wrench-Monkees" style, much appology if somebody else thought of it first and Wrench-Monkees ripped off their idea ... psychically some-how, like that K110 bike....

You know, I don't wanna go off on a paranoid rant here. I will TRY to make this short, but that's not my forte'. I don't "Tweet". Ha ha. Anyway, yeah. You DO realize that there's a lot of demographic information being culled from all of these social networking sites out there. You don't fool yourself into thinking that the "What is your income bracket" and "Are you thinking of buying a car in the next six months" questions are completely disconnected from all of the other crap they ask for inexplicably? Do you still think your location information is collected for some vague legal distinction, such as if you're in China then they forward your e-mail to the state security apparatus? Well, that too. But as much as anything, while you would think that the people surfing your pre-teen daughter's chat-rooms would all be perverts, (well in a way this IS perverted) but there are probably a lot more lower level employees, interns and the like, of major advertizing firms ... not just the magazine types or the clothing designer people and all of that, but consulting firms that are hired by all of the above. And they're out there trying to figure out how your kid's brain works. I've often thought of enlisting their services myself! Ha ha. But yeah, now think about how people have always said "I sent an "Angry Letter Letter To The Editor" type of appeal to Honda or Kawasaki and the like, and yet they never listen to what people think? Well, how do the major manufacturers keep "abreast" of the cultural zeitgeist? Or rather, how do they come up with such a crappy interpretation of which, such that there are still so many plastic rockets out there, despite everything else that's considered tacky and out-dated about the mid-'80s to mid-'90s epoch, and at the same time have some very beautiful prototypes out there that never make it to the road? Obviously, the big four have gone from smally family run or family-like organizations that could show-case the brilliance and vision of a few talented individuals, and become mired down in the bureaucracy of the new corporate model. Anyway, I think it's entirely possible that people's ideas could be stolen off of the 'net, from these forums. At least, I sincerely hope so. Ha ha. Maybe then, with enough discussion, not only will Triumph and Moto Guzzi and Honda and Ducati and yadda yadda yadda come out with JUST ONE "retro" styled bike in their line-up. What I would love to see, is an option for every damned bike in every line-up. That's why I might just have to take the wire wheels and body-work from this project and stick a version of them on every cheap crotch rocket I could ever afford.

People have just gotta win over the "haters" on the other motorcycle forums who will restore to one of these delicious bikes as "cafe gay", and I don't mean by distancing ourselves from the 1% to 19% to 100% (latent) homosexual demographic of the cafe scene. Not suggesting here that we do anything to mess with our unity here. But yeah, perhaps a few judiciously placed photos of Hayabusas being used as mini fast-mobile parade floats during Pride Week, piled up variously with inverse pyramids three stories high of drag queens dressed up as Vegas Show-girls or perhaps some kind of hard-core old school Harley chopper with a dozen leather-daddies contorted into an elaborate 69-96-1-3-69 tantric love orgy position, perhaps an overview of the parade showing how many people are wearing brightly coloured race leathers or even just tight fitting Alpinestars ventillated mesh jackets. Not to condemn, not by a long shot. I'm proud of those fellas too. What I am saying is, we need to show the world that ALL motorcycles are gay, not just the cafe scene. Maybe then people will stop using all of these homophobic epithets when they bash our whole aesthetic sensibility.

Oh, one thing we could also do a bit differently: I bought a copy of "cafe racer" when I was headed out for a four hour bus trip the other day, I was going up for some spinal injections, even if I was riding in the middle of summer I'd probably be best to go as a passenger on the way home.... But yeah, what I usually read is "Classic Motorcycle Mechanics" or "Motorcycle Classics", because they're the two main bike rags that show-case older bikes, without too much emphasis on the British scene, they have a clear preference for the Japanese bikes and the '60s to the early '90s era. While still being balanced, and having their share of British singles, twins and triples. Fact is, the very first copy I ever picked up, had a custom built Triumph "Quadrant" four cylinder on the cover. And consequently, I have spent enough dough to fix my bike ten times over, on those damned magazines. Not a waste though, I gave 'em to a good friend who's a brain-injured senior citizen, a former motorcyclist from the South of England in the '60s-'70s. I used to take him out for rips around town on my DOHC Honda, actually this time around I hope to have it completed before he dies so I can put him behind the bars. Probably not a good idea, seeing as I've been helping him out with some left-over pain meds. But then, being that I still take the majority of them, it's probably the safer option.... But yeah, anyway, I picked up a copy of "Cafe Racer" magazine, and I read it from cover to cover and thoroughly enjoyed the whole thing.

The hair and make-up was impeccable. The costume, superb, a real authentic period historical drama in the vein of "The Scarlet Pimpernel". I wouldn't actually say that it's the guys themselves who pull off the whole vibe. There's nothing definitively flaming about their whole style of dress. Other than, perhaps their slavish devotion to detail, colour co-ordination, and accessorization. And this is coming from a dude who carries a "man-purse" (it was a GIFT) and paints his finger-nails and toe-nails while sitting at a "tea party" with his daughter and her friends. (Well, at first it was a "tea party" with the stuffed animals and shit, but now that the girls are a lot older, it's more of a "tea party" if you catch my drift. I always said that I would trade the kid's highschool purchased weed with the medical grade compassionate aid society stuff, because I didn't want her to get dusted with PCP, as happened to me and my close friends back in the '80s. Of course, this being in Calgary, it's all high test stuff now, and what the kids were packing around blew my lid off....) But yeah, I'm not going after anybody's dress style here. Well, not the dudes. And now I am really going to channel the spirit of the art students who raised me, many of whom were lost in the first wave of the AIDS pandemic, and I will be truly harsh and un-flinching in my critique of the hair-styles worn by the chubby girls who hang around the scene. Yes, what I am saying is that the women who hang around the whole cafe racer scene and try to pull off a "pin-up" look, just come off looking like a bunch of "Fag Hags". And hey, it's an affectionate term. I've even dated a few of them, one of whom I am her only ex boyfriend who didn't switch teams after we broke up. Ha ha. But yeah, my first wife we used to go out thrift shopping for fabulous fifties clothes. Let's just give you a picture, though I had a bald head (no wait, I am now remembering the horrible "Roman" looking hair she made me wear while my hair-line receded, and how I did wear my head shaved for a time while we still dated, but how much she hated it ... good riddance!) despite she being the only one with the long hair, we still had a semi-matched pair of ex beauty-school Betty Rubble and Wilma Flintstones looking hair dryer chairs, you know the ones with the big dome over-top so that you can properly dry and set your "Bee-Hive" hair-do? Yeah, this didn't go so well with her little green metal flake Bell helmet, with the green aquarium suction cups holding old '80s "deely-bopper" antennae (in yet ANOTHER Flintstones reference) she would wear her hair up in a full-on B-52's "What's that on your head? A WIG!" Bee-Hive, and we didn't just go off the crate full of vintage Mutoscope cards I found in a warehouse at work back in '90-'91, we went to the Library and rented all of the old movies, especially Doris Day musicals - we even wore our flannel pajamas while singing along to "The Pajama Game" (Seven and a half cents doesn't buy a heck of a lot. Seven and a half cents doesnt' mean a thing!) That's enough for me to get an automatic washing machine" At first it seems to make a joke of Trade-Unionism, with it's half-hearted display of Taylor-ist factory practices where people still had time to dance around without having a limb chopped off because they broke the pace of work.... But the real mockery is the enlightened self-interest that's become of the unions today. Just don't be put off by the movie, it's actually pretty good. But then, I like most of the old movies, while some are such gems that everybody should be forced to watch them, I'm willing to sit through any kind of fluff just so long as it's shot in techno-color, even the collected works of Elvis Presley.

Okay if that is seeming really really gay, let me just say, the one line from "The Pajama Game" which she sang best was "GIVE IT TO ME EVERY DAY FORTY HOURS EVERY WEEK" ha ha. Mmmmm. "That's enough for me to be livin' like a king." Heh heh. And though I may have been a stand-in mannequin for my high-school's beauty culture class, I used it as my own personal rub-and-tug massage parlour, and the hair and nail work was often done by my first "wife"'s best friend, (aka the towel girl, aka the ballast on the other side of the human see-saw) just to keep up the appearance that I was unwillingly compelled to submit to having my hair coiffed about and my cuticles buffed, etc etc. Never mind the fact that she looked just like an old school movie-star, a bit like a Marilyn Monroe, (and her friend looked a bit like a TV witch) actually she looked a heck of a lot like Doris Day in "The Pajama Game", especially in plaid flannel. Not like Doris "Stockwell" Day, from Canadian conservative politics. But yeah, what I am saying is that the realy red-blooded hetero-archetypical hero of your whole cafe racer sketch NEVER goes for the bad girl. He goes for the most preppy little blondie from the cheer-leading squad. If you really wanna go for the 1950s thing, you could play like Jerry Lee Lewis, and ride with your fourteen year old cousin on the back seat of your bike. In which case, you are gonna LOVE the calendar I'm gonna put together when my bike is done, and all of my daughter's friends whom I practically raised single-handedly from age six or seven through junior high school. I figure the bike will be done by the time they turn sixteen or seventeen, and I won't get into any trouble over distribution of the pictures. Ha ha. Gonna do a whole "Mods Vs Rockers" thing with my girl's scooter, my old C70 Passport scooter, and the cafe I'm making from my old KZ440 plus the DOHC Sand-Cast. It should sell like hot cakes. It's not gonna be anything pornographic or anything, gawd no. It's just gonna show-case all of the hair I have cut and dyed and styled over the years, the help I gave them with their make-up all the way since they first started wearing the crap. Over the years I've seen a lotta make-up, but when I was a teen the whole "invisible" look, and the "less is more" sensibility really took hold. So as much as anything, I helped them to not cake the crap on like stage-craft grease-paint. (Something which a lot of the "pin-up" chicks nowadays could really benefit from.) Okay, now you've gotta be wondering. I ran my own little beauty school? Good Lord. Or baking all of those cookies for slumber parties, (so many damned slumber parties that it cured me of my fetish for plaid flannel pajamas AND dirty panties being that I had to pick up and then wash about a zillion of each) at this point you must be picturing me in full drag wearing a blue cotton button down shirt and khaki dockers, with a blonde shoulder length wig on my head, styled "just so" aka "Martha Stewart Drag". "It's a good thing." Ha ha. But no that's just the role that was thrust upon me by a workaholic girlfriend, which I just picked up and ran with. BUT, that's how come every little chicka in about three different high-schools "owes" me a modelling session when the bike is done, 'cause I've slaved over their hair when I should have been doing the bikes.... But yeah, don't expect anything like that beautiful calendar put out every year by that Forrest Lawn Vietnamese bakery, the one they refuse to even talk about with white guys because it's got nothing but naked pics of all of the prim and proper Asian ladies that work as bank tellers and shop-keeper in the local community.... One of my bosses hooked me up with it, years ago when I was working in "Chinatown". It would blow your mind what those guys have going on down there. Damn. Ha ha. But yeah, MY calendar will be much more family show. But as time moves on, and the bike winds up in "The Horse backstreet choppers" magazine (some pretty good cafe bikes, and often as not the rough looking chicks in the pictorials actually ride the bikes, they're not just sent there by their agent as a rest between porno shoots) there will be about fifty different girls to model on the bike. And then I won't be able to read it, (not so much because they'd be scantily clad, I've had that image burned into my retinas over the years all the way up to accidentally busting in on their furtive make-out sessions with a whole generation of young men who will now have my face next to the word "cock-blocker" in their mental dictionary. No, more because I'd break down as I attempt to recite the last pages of Louisa May Alcott's "Little Women" from memory. "They were no longer little girls. They were little women." ( ) and then I would probably cry and bawl "They're all grown up now! Boo-hoo-hoo!"... but all the same, "The Horse" would be good publicity, even if it does seem sometimes like you just need some half naked young girl and you can get pictures of any Horrible monstrosity of a back-yard chopper into it's pages.... Ha ha.

But yeah, that's my theory about why people always say "Cafe Gay". 'Cause they're waay in the back of the closet, buried in a pile of their mother's clothes, about their OWN bike scene's gay-ness. But more than that, because the chicks in the Cafe pictorials, who go all out for the retro-pin up style, they don't use the proper reference materials when they're throwing together their look. They just shop at that same damned little boutique where I go with the girls to buy all of that damned hair dye. Hey, at least it's not permanent. Back when I was their age, and I was dying my OWN mohawk, if you messed up with the dye you might as well have drawn on top of the stain and pretended it was a tattoo... Ugh. That said, it's still a pretty damned cool magazine. Right up there with a lot of other fashion magazines I have enjoyed over the years. For instance, my sister bought every copy of Andy Warhol's "Interview" magazine, (you wanna talk about the cultural zeitgeist) with it's early coverage painters such as Jackson Pollock, of the photography of Annie Lebowitz not to mention that of Robert Mapplethorpe, Pee-Wee Herman, and blue porn "actor" Jeff Stryker - Come to think of it, I think the main thing that connects these two magazines is that they're so damned gay....

Okay, so maybe we could keep the girls with the over-done scarlet lip-stick with the horribly done black eye-brow pencil for lip-liner ring around it, maybe we can even keep the horribly done cheap looking "Sailor Twink" tattoos with their inch thick out-lines, maybe we could even keep the pompadour "Quiffe" rooster-hair, just so long as we DO also include some very preppy looking little blondies in bee-hives and pink "Edward D Wood Jr" cashmere poodle-sweater cartigans, high heeled pumps, etc. All safety coniderations aside, if you wanna achieve that certain look, then the hag on the back of your bike should look like she was just serving up burgers and milk-shakes at the drive-in restaurant, and she would still be wearing her roller-skates. Preferably riding side-saddle, in a fashion indicative that she did not get onto the bike willingly, that you sort of scooped her up and you're blasting off to look-out point for a little bit of date-rape. When you've got your honey done up in matching his-and-hers leathers and pudding-bowls, and she's got that garish war-paint on with the faux eye-lashes on, (often times one of them blown by the wind onto the lower lid of the opposite eye so she looks like "Your Humble Narrator" from "A Clockwork Orange") it just looks like she's your sister and she's come along to stick up for you if anybody tries to gay-bash you. Hey, I don't make up the rules, I'm just telling you like it is. Maybe I ought to write this little appeal to Cafe Racer magazine themselves. Ha ha.

But yeah, that's my thinking behind getting something more Cafe-Racer-esque from the major manufacturers. The Euro-trash scene is so well entrenched that the folks who rubber-stamped the Guzzi V7 cafe racer were tracked down at one of those "bubble party" raves, so I doubt they were hung up about it. It sure would have been nice though, if they could have seen fit to do that with the V11 California, instead of pumping out a bore-out V-50 Monza with laughable aspirations of performing anything like a Telaio Rossa, something which should be no problem for a modern bike, even a decidedly already retro twin like a Guzzi. Why didn't they do this project on one of their super-bike chassis? What a bunch of twits. Same goes for Triumph. They should have done a treatment on their Speed Triple, and gone in for a T-160 Trident replica, instead of the Bonnie they did. Even my 'F should have no problem blowing those things away. Especially once the 1123cc engine get's built. I'm thinking that pretty soon Cycle Exchange is gonna start rebuilding the DOHC. Probably gonna need a lot of aftermarket parts, if they're gonna make very many 1100 or even 1000cc shaft drive bikes, 'cause there weren't a lot of those bikes made, and they need to be preserved in any case. Still, Cycle X has been coming out with more and more great parts for the DOHC, it's very promising. If NOT, well the 'F-orum is a great resource, and there are lots of good engine builders out there on it's boards. Just sayin', the new retro bikes won't be able to handle the real classics that are coming up on the Cafe scene now, the only sensible thing to do will be to build a proper modern superbike as a TRUE Cafe, wire spoked wheels etc, or they're just gonna get stomped by the old stuff which is coming up now and is gonna be a lot more common than your typical Ducati Sport-Classic or Triumph Bonneville, and then you can forget about them continueing to build bikes that are just flat out trumped like that. Which is a bad thing, and at the same time a good thing. Depending on what side of the fence you sit on. It won't be as easy for people to just grab an off the shelf "life-style" without paying dues by whipping up their own custom builds.

Whatever. Sorry about the long rant. I was just hoping that somebody take a tape measure to their seat ... ha ha that sounds bad ... so that I can whip something up the same size, and then wrap the whole thing up in tight black vinyl like a pictorial from Eric Kroll's "Fetish Girls" ( ) ... that is to say, a seat PAN from an old Diecast or Sandcast or equivalent. I'd just like to be able to use an off the shelf reproduction seat cover and have it fit "just so". It's a good thing.

I might just add, there was a dude on fleabay a while back, was making cool custom covers for any seat, you send him your ratty old one and he'd sew up a new cover in the same sizes, and they were mostly listed for twenty-five bucks. Dunno if this service is still available or not. They were a really cool late 70's looking thing, all poofy like those down filled vests with the horizontal bars of stitching. VERY authentic to a '70s custom, I think the whole method comes from an article that every body got his girl-friend to copy from, 'cause I remember seeing a lot of this type of seat on all hand-made bikes badk in the day.

Oh, I should also mention that I am also looking for the scrap passenger peg "triangles" that ya'll keep cutting off of your SOHC frames, as I wanna weld them onto my DOHC frame, so I can get rid of the big alloy plates that cover the swing-arm and everything, on these Super-Sport models. Magni made a custom frame for the CB900F, where they were just welded steel triangles, much like you see on the DOHC CB750K. But I am picturing something more like the Sand-Cast again here, possibly a larger loop off a 500 or 750 SOHC to locate my passenger pegs, and maybe some tiny little ones off a CB350F or CB400F, to use for my own rider rear-sets. Of course, when I find the right sets I want, I'd be happy to pay for them, and shipping of course, beer money for a drink while you package it up ie shipping AND handling, etc. Or, maybe I have something to swap for it, we'll see. I already posted a new thread for that in the Rear-sets forum, so we'll see. Anyway, thanks for taking the time to read my too-long of an obscene rant I just posted here.

P.S. "Post-Script Standard Disclaimer": Sorry if anybody interprets any of the aforementioned rant as homophobic, 'cause believe me, it's a "term of affection" when I borrow a loan-word or two from Hate Speech. In this age of deconstructionism and empowerment the language of the oppressor blah blah blah blah...



Been Around the Block

COME ON, people! I just need the measurements of a SOHC '69 CB750K seat pan! PLEASE? I don't wanna have to start pestering people one by one....



holy shitbegone.
longest post i ever saw.

didn't read it but helping you bump it up.


Been Around the Block
Aha. well how very astute of you to figure out that it's a "BUMP" as it were. I would, and I could, but it would probably fuckin' kill you. Dilaudid. 40-80mgs per dose, (though typically 40mg 'cause I'm trying to dry out a little bit) usually every four hours for a small one, maybe enough to knock me out and I'll make seven or eight hours. I hurt my back pretty horribly back in '99 - and this was after a life-time of what people call a "bad back".... Anyway, at this point maybe I WOULD be willing to get busted for dealing drugs just to get the information I was asking for in the first place: What are the fucking dimensions of an early Sand-Cast/Die-Cast, 'K2 'K3 etc CB750??? Jeebuz these forums can be useless sometimes!



Over 1,000 Posts
SoyBoySigh said:
What are the fucking dimensions of an early Sand-Cast/Die-Cast, 'K2 'K3 etc CB750??? Jeebuz these forums can be useless sometimes!


Not for nothing, but this is NO way to get an answer around this place. I dont have an answer for you, even if i did, i probably wouldnt help ya out with that kind of attitude.


Been Around the Block
Oooh SNAP! Oh, but what a minute. I'm not sure just where you're coming from right there. I can't tell if you're admonishing me for offering drugs OR for NOT offering drugs, in exchange for information. OR whether you're nattering nettiquette, Niss Nanners, netcetera.

Honestly though, I've asked the same question around here a half dozen times. My normal 'F-orum is full of all sorts of good advice, even when it's not solicited.... But here I thought there'd be SOMEBODY around who's done a seat on a bike without jumping on the after-market Cafe-Kit bandwagon, or going the NOS route, just SOMEBODY who'd have a mind for replacing their stock seat pan with fibreglas rather than steel at least. I mean shee-it, there's gotta be a huge pile of rusty old seats where you guys toss 'em when you put on your Carpy seats.... No, wait - I've already found that it's called E-bay. Ha ha.


Facta, non Verba
Try heading over to, they can probably help you with this specific answer. There aren't going to be too many on this site that will know the dimentions you are looking for, let alone even have a seat pan for a sandcast to measure.

Also if you have asked this question "half a dozen times" here and still haven't gotten an answer, chances are it isn't that it is being ignored, it's that nobody has the information to share. Would you rather havbe everyone just chime in with a "good questions, I have not f'ing clue"?


Over 1,000 Posts
Didnt even read the OP at all. Dont have the time
The web/forums is not a help desk, remember that

Sandcastonly is another site that might know, but most of those guys are also on the sohc site too.

What is it you want to know? The pan from a sandcast is not really all that different then the K3-K6, the "ducktail" part is in the foam and not the pan.
So what the hell are you trying to do again?

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