Rear wheel swaps - Changing to 18" rear on 11 & 12 -???


Technical information and Q&A applicable to all years and models of Goldwings
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SoyBoySigh
Posts: 4
Joined: Tue Oct 04, 2016 3:19 am
Location: Southern Alberta, Canada
Motorcycle: 1982 CB900F aka "CB900K0 Bol Bomber" - extensive mods with all sorts of 'WING parts, GL1100 vented rotors, GL1500 fork, GL1000 wire-spoke front hubs (putting one into a REAR wheel too) GL1000 master cylinder, etc etc - I'm working on a wire-spoke converted version of the GL1500 shrouded front brake, with the GL1500 hub cut out & drilled for spokes, but am thinking I'll use the PC800 Pacific Coast front hub.....

Rear wheel swaps - Changing to 18" rear on 11 & 12 -???

Post by SoyBoySigh »



For some time now, I've been dreaming of grabbing a 'WING as my next project, once my "CB900K0 Bol Bomber" and "KZ440LOL" are finally done with, along with the 'featherweight' DOHC-4 or perhaps instead of it. (Remembering I had only joined Gold-Wing forums 'cause of the GL1000 front end parts I'd used on my CB750F wire-spoke wheel swap etc) I'm OBSESSED with the idea, and yet this would be my first SHAFT-DRIVE bike, and I've been spoiled with the ease of wheel swaps - though from a chain-drive perspective the rear DISC stuff can still be a pain in the "rear end" (pun unintended) the shaft stuff is daunting - Which is why I've been so obsessed with it long before even finding the 2nd-hand BASKET CASE GL1200 to begin with (stripped NEKKID and with a front-end swap, seeking exhaust and carburetor changes, a new tank etc etc - Why get the whole bike in the first place?)

So ANYWAY, I've just had a bit of a break-through, and I figure I should copy & paste what I've just been posting to one of the "Darksider" threads:

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I'M far more interested in moving the cross-brace toward the pivot area, so that an EIGHTEEN INCH rear wheel would fit - Either a 2.75x18" Comstar using '81-'82 CBX1050 "Pro-Link" model's rear wheel, rebuilt with the GL Comstar shaft-drive type hub - OR a "WELD-UP HUB" mod ala the CB900C based wire-spoke CHOPPER built by one "6pkrunner" on the CB750C.com four-ums, a brilliant method involving a drum hub hollowed out side-to-side, some fillet welding - and ANY read carefully ANY type of donor hub, spooled down to a cylinder on a lathe - I've got some "drum-drilled" rims in 3.50x18" Super-Akront and 4.25x18" Akront TR profiles, as well as Harley pattern drilling on 4.25x17" & 5.00x17" 40-spoke Super-Moto rims, as well as 3.0x16" Borrani & 3.50x16" Super-Akront rims drilled to suit the Honda rear hubs - and a 3.00x18" Morad drop-center shouldered rim (ie Borrani style) that's un-drilled. Plus a couple of 2.5x18" rims from Harley XLH rear wheels which means they're drilled to suit the Honda FRONT hub - Several combinations in there for matched style rims in some VERY interesting sizes!

The GOAL of course, being a Doncque "DLF-1000" style race-replica, with a Beemer boxer-twin full racing fairing, ideally with the same twin headlight look & all that - Too bad we can't get a replica of the original Doncque frame, or even the Rickman/Dresda "WING THING" for that matter. But I figure the GL1200 is the better place to start, so that with the change in overall final-drive ratio & thereby GEARING, the feel would be like a GL1000 stocker, but with a couple of extra overdrive speeds for a higher top end and lower RPM on the highway, etc etc.

It only just occurred to me though, that the swing-arm needn't be STRETCHED with a longer weld-up drive-shaft etc - You wouldn't wanna lengthen the WHEEL-BASE in any case! No - what's REQUIRED, is that the cross-brace be moved forward, and a custom UNDER-BRACE be added, like the '82 AMA Superbike racers, Freddie Spencer's & Mike Baldwin's "CB750F" AHM 1032cc monsters, once had - it's like a whole 2nd swing-arm welded under the original - Well it needn't be THAT elaborate, but the cross-brace COULD be modified in such a way that the arm is actually STRONGER than stock - albeit slightly heavier overall.

What would be AWESOME, is if we were to take the later era CROTCH-ROCKET swingers, like people are always modding onto their "STARBUCKS RACER" style crotch-rocketry .. ahem, "gentrified" (((as in the old "greasy spoon" CAFE has been replace by a Starbucks - get it?))) fugly-fied (once-were-) CLASSIC SUPERBIKES - UGH. -

A swing-arm like that could be put to FAR far better use, if swapped onto a GOLD-WING, wherein you'd remove one side and weld in a huge thick-walled hollow alloy TUBE - with a flange on the end to bolt the PUMPKIN onto - the flange and the rubber boot seal at the other end would be about the most EASY mods you could feasibly DO to a swing-arm, certainly easier than making late-model adjustable CHAIN-TYPE axle mounts - Heck even the flip-side could have the fixed small-bore axle clamp fitted, rather than worrying about an adjuster slipping loose. The whole damn thing would be ALUMINUM, far beefier looking than the OEM swing-arm, but lighter weight I'd bet, and possibly even stronger - though strong as OEM is more than sufficient and so if weight savings were the only goal I'd still regard that as a massive success!

For a more PERIOD-CORRECT version, it could be built from the CAL-FAB unit from my "CB900K0 Bol Bomber", or the reasonable facsimile which was fitted to the Suzuki Katana some four or five years later. You'd wanna be choosy about which of the later model crotch-rocket swingers you'd fit to the 'WING, 'cause the goal would always be to do a PERIOD-CORRECT style race-replica, not another "STARBUCKS RACER"!

Honestly though - just moving that BRACE seems like SUCH a simple mod by comparison! Just a bent hoop of tube around the size of a CB900F swinger, bent just tight around the fat 18" new wheel, and welded to a point equidistant from the axle and swing-arm pivot tube. Now THAT could make for a really decent under-braced set-up, and it might even weigh less than stock!

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I think it could really work! Still - just a brain-fart. Thought I should bounce it around off of YA'LL to see if there's something I'm missing?




-Sigh.


SoyBoySigh
Posts: 4
Joined: Tue Oct 04, 2016 3:19 am
Location: Southern Alberta, Canada
Motorcycle: 1982 CB900F aka "CB900K0 Bol Bomber" - extensive mods with all sorts of 'WING parts, GL1100 vented rotors, GL1500 fork, GL1000 wire-spoke front hubs (putting one into a REAR wheel too) GL1000 master cylinder, etc etc - I'm working on a wire-spoke converted version of the GL1500 shrouded front brake, with the GL1500 hub cut out & drilled for spokes, but am thinking I'll use the PC800 Pacific Coast front hub.....

Re: Rear wheel swaps - Changing to 18" rear on 11 & 12 -???

Post by SoyBoySigh »

Whaddya think? Would it be feasible? Seems like the width would be there, that it's just down to the clearance up FRONT, and that some triangulation of some sort SHOULD replace the stiffening the original cross-rib does.....

I think it would kick ass, an 18" rear on GL1200 - either 140/70-18 Pirelli like I've got on the "Bol Bomber", on a 3.5x18" or 160/60-18 bias-ply OR the 160/60ZR18 which fits the same rim width - supposedly the 150/70-18 will fit either of these rims, and I suppose I'd be hung up over the extra weight, but then again my later "TR" profile rim has bead retention ridges (darksiders know what I'm referring to) while the earlier "Super-Akront" "skinny" rim doesn't have 'em - therefore the wider rim could be sealed up TUBELESS with aquarium silicone......

The "Weld-Up HUB" mod from the "6pkrunner" bike seemed like the GL1100 rear hub "core" and the hollow CB750K rear drum were a perfect MATCH - Nevertheless I'd be tempted to try any other smaller 40-spoke hubs, or a 36-spoke for that matter IF that's the type of rim I had on hand - or even something drilled for still MORE spokes for that matter, if there's a custom drilled rim from a blank, a dimpled (gotta be dimpled for the proper period-correct look) could be done in 48-spoke and use flanges from a Kawasaki KZ650CSR rear drum - OR custom flanges I suppose, where you'd be able to pick something weird like 44 spoke or thereabouts - 48 spoke is probably about as strong as it would need to be - But 40-spoke standard Honda drilling is about all we're ever gonna find in a PERIOD-CORRECT custom aftermarket alloy rim, let alone in the sizes we'd be looking for. The point being, ANY of the rims which could be found for it, they'd work on the conversion probably even a conical type original hub 'cause a new flange could be cut with whatever hole spacing was required.

Plenty of weight would be ditched off the OEM rear wheel, and more yet if the rotor were swapped out -the 5-bolt Comstar hubs seem like they'd work with the ZRX1100/ZRX1200 discs 'cause of their 100mm center hole & 120mm bolt circle - might still need an off-set spacer but at least the basic pattern is spot on! Don't like the LOOK of a later crotch-rocket thing though, I'd really rather shoot for a proper '70s-'80s look, with the RCB/RS1000 as a template for any Honda WORKS spec chassis & running-gear design - ideally non-shouldered/flanged/valanced rims polished as much as possible to look like the STREET version chromed-steel D.I.D. rims, well either that or some widened lightened COMSTAR wheels with Akront "NERVI" rims on 'em - 43mm TRAC fork using '96+ ST1100-ABS Pan-European components - as much as possible of an OEM design ethos/pathos, as "Retro-Fried" as humanly possible ie single-puck calipers even if it must be aftermarket like AP-Racing CP2696 or better yet the GRIMECA stuff which was done to the exact same pattern. OEM '75-'76 REAR calipers, left and right handed versions, cut & drilled to fit the forks etc etc - IF at all possible, that is....

I picture it using a BEEMER BOXER Endurance Racer fairing for those huge bulges easing out to the relief holes for the heads & pipes, suitably relieved for an uber-sexy over-sized RAD, it goes without saying.

Ideally the front hub would be the CB750P7-II Canadian/Filipino FIVE-bolt dual-disc wire-spoke 40-hole front hub - VERY rare Unobtainium,
SoyBoySigh
Posts: 4
Joined: Tue Oct 04, 2016 3:19 am
Location: Southern Alberta, Canada
Motorcycle: 1982 CB900F aka "CB900K0 Bol Bomber" - extensive mods with all sorts of 'WING parts, GL1100 vented rotors, GL1500 fork, GL1000 wire-spoke front hubs (putting one into a REAR wheel too) GL1000 master cylinder, etc etc - I'm working on a wire-spoke converted version of the GL1500 shrouded front brake, with the GL1500 hub cut out & drilled for spokes, but am thinking I'll use the PC800 Pacific Coast front hub.....

Re: Rear wheel swaps - Changing to 18" rear on 11 & 12 -???

Post by SoyBoySigh »

The whole point of the FIVE-bolt front hub, would be to utilize the GOLD-WING correct rotors - you could use this hub on '75-'77 GL1000 and if you fit the '77-'78 CB750A Hondamatic front discs, you'd have the same look as the originals (okay well the Hondamatic like 'K-bike discs were 296mm and GL1000/CB550 dual discs were only 276mm, but you could always cut 'em down, replace the outer rings by drilling out the rivets etc etc - the point being you'd get that whole '69-'76 SOHC-4 'K-bike & early 'WING aesthetic) but it would WEIGH substantially less, first of all 'cause the CB750P7-II front hub is a thin & delicate Yo-Yo shape whereas the regular 6-bolt hubs are hollow - More to the point it's the 5-bolt vs 6-bolt thing AND they're shorter threaded bolts rather than full-width through bolts, so the hardware's probably ditching an even greater proportion than the cast alloy center itself!

But beyond THAT whole CR750 replica lightweight version, there's also the 296mm version of the DISHED one-piece rotors off the CB1100RB for a '78-'80 GL1000 & some GL1100's kinda vibe.

OR there are the double-thick vented rotors from GL1100A Aspencade, CB1100RC/CB1100RD - or their silver-centered counterparts from GL1200's

OR one could rebuild the spiral-pattern center carriers from the 276mm composite rotors (CB1100F/CX650T/CX500T GL1100/GL1200 & VF750F/VF1000F Gold Boomerang rims etc etc - Rebuilt to a 296mm diameter or even larger!

The 43mm TRAC fork from '96+ ST1100-ABS have a 316mm stock rotor diameter, so whether it's rebuilt with two RHS legs for a double-sided TRAC anti-dive mechanism, OR just used stock for a GL1100/VF1000R vibe from the 1/2-TRAC set-up & the stock black paint - the double version would be a perfect replica of the NS500/NSR500/RS500 racing forks from mid-'80s works bikes - the big orange "SHOWA" stickers are available from the dirt-bike crowd, too.

But whatever is done with the 43mm TRAC fork it's a fantastic upgrade for even the 41mm stuff, and considering the AHRMA limits "forgotten era" racers to 43mm max, I'd keep it there rather than jump up to 45mm stuff ala early Yam R6 etc - Besides it's all about the TRAC thing, 'cause that's some solid '80s HONDA tech - right?

Either which way, the 5-bolt hub option would be THE way to go for any wire-spoke Honda conversion of '80s persuasion - Including any DOHC-4 CB750K (-'Z/'A'/'B/'C & 'LTD versions that is) to upgrade their single 276mm disc with a dual 296mm in a 39mm fork - just about an ideal package for the 736cc stocker, imho - well, that AND a smaller lighter rear drum hub ie CB500/CB550 type of deal, IF you could fix the damn cush-drive design that is, perhaps the KZ400 40-spoke rear drum would be a decent substitution. But yeah - an upgrade chassis & running-gear package for the DOHC-4 CB750K would ROCK - the key being to keep the original aesthetic. Alloy wire-spoke rims in 2.5x18" & 3.5x18" -

OR, for any & all of these bikes, a decent COMSTAR wheel would be to rebuild the early CM400 1.85x18" "SILVER" 1979 style non-"reverse" 5-point Comstar wheel - it'd need the dual-disc hub preferably early type with the full lip on both sides, and an Akront "NERVI" rim in 2.5x18" from Morini Excalibur, which should be anywhere from 35%-50% lighter than the stock D.I.D. brand rim in the same size - it lacks the hollow double-wall shoulder of the OEM item, just a thin wall single-thickness rim just like the regular Akront "TR" profile but with the addition of a central flange/ridge "nerve" or "nervio" in Spanish and/or Italian - The TRICK would be to dig up another such rim in a decent size, although there IS an example in 3.0x16" from that very same Morini cruiser - Would make for one hell of a lightweight pair on a CB750C based featherweight racer, or a GL1100A retro-fried - with a 3.50x18" or 4.25x18" Akront "NERVI" rim, it would be one hell of a pairing, heck even just a 2.75x18" from '81-'82 CBX1050 rear wheels for that matter, would make one heck of a wheel-set for a '78 CBX, '77-'78 CB750F2, '79 CB900FZ or CB750FZ etc etc - Or more to the point a later year GL1000 - There's a D.I.D. brand center-flange rim in 4.0x17" from the Yamaha Super-Tenere with some spoke holes in it sure but it SHOULD work out with the 10 holes of the Comstar wheels - Would be nice to use the 3.0x16"-er on a BOOMERANG wheel, or 6-point VF1000R/NS400R Comstar wheel, what HAVE you - this is the same rim used on for instance, the Ducati "SUPERLIGHT" special edition Super-Sport from the '90s that is - VERY much a proper top-shelf high performance racing spec rim -

If only we could get the MORAD people to start churning 'em out again! Picture how that would change things for the COMSTAR clad Honda owners, in much the same way that alloy rims for wire-spoke wheels have changed things for the earlier models - It would be a GAME CHANGER!

And of course, THEN you wouldn't need to bother with the "weld-up HUB" conversion, ala the "6pkrunner" wire-spoke CB900C based wire-wheel CHOPPER - just swap the "spokes" if you want a more retro-fried aesthetic, but above all else swap out the rims for a lightweight rim set in just about any width or diameter you could dream up! With a low aspect tire suited to a wider rim, you might not even change much about the actual dimensions (unless that is, you wanted to modify the SWING-ARM, like I was sayin') just a wider rim and lower shoulder in more or less the exact same (nominal) SIZE of tire - I'd rather like to think of a super fat 18"-er, 160/60ZR18 radial on 4.25"x18" rim - whether that's a wire-spoke version OR the Akront "NERVI" or for that matter, perhaps even a weld-widened D.I.D. type Comstar wheel, like KOSMAN INDUSTRIES used to do, before they went defunct - the 17" & even 16" stock wheels could be welded to a larger diameter wheel - One of the craziest weld-widened rims I've ever SEEN was a "SUPER-AKRONT" brand, "inside & out" or so to speak, with the more common chopper-esque 3.50x16" center laced to a Harley rear hub, with the 3.50x18" version split & welded onto it's sides, for a full width of a nominal 5.75x18" but the most enormous "DEEP-drop-center" you could imagine - the trick would be in finding an INNER-TUBE to work with such a beast! Perhaps you'd want to add a bead-retention-ridge so as to seal 'em for tubeless tires? EITHER way, it's an awesome looking rim, and period-correct as all get out - Thing is, back then you'd only have access to huge square-shouldered DRAG racing tires, 200-spec with "GOOD YEAR" in raised white lettering etc - But NOW there are these awesome new 180/55ZR18 CROTCH-ROCKET RADIALS -

You can see the latter on the "Van Geert" CBX over in Holland, on a rebuilt Akront "NERVI" type Comstar, fitted with 3.00x18" & 6.00x18" rims, both of which I let slip through my fingers while hoping something BETTER would come along - ignorant of the new 180-width tires, hovering over whether to buy the 2.5x18" or 3.0x18" for a front wheel when I should've bought 'em BOTH..... Ugh. Well - if the CBX builder had followed MY plan, his twin-shock CBX1000 could look just like a '78 vintage introductory version, with 296mm dished rotors up front, perhaps a rear dished rotor cut down to 276mm max more like 260mm preferably - With a '78 style CBX1000 and parts like THAT on hand, there's nothing to do but shoot for the Pebble Beach BEST IN SHOW award - a project like THAT could certainly garner attention from the likes of MORAD - and then WE'D all benefit from the trickle-down!

Well - maybe in another life? Ha-ha. In the mean-time, I'M just gonna have to try and build that FRONT wheel for the time being - gonna grab the 3.0x16" too, if I can get it for cheap - beyond that I'll be looking for a nice un-dimpled Akront TR profile rim in the right size, to have a flange WELDED into the center of the damn thing, machined down to the correct thickness & absolute concentricity - A pain in the ass to fabricate something like that, but there's at least a chance of pulling it off, rather than just praying that the "wheels of fate" would land an actual "NERVI" rim in one's lap.....

But yeah - I'M gonna build the FRONT wheel - if for no other reason but that the aforementioned "CB750P7-II Canadian/Filipino front HUB isn't forthcoming, and the 2.5x18" rim in an equally lightweight non-shouldered period-correct style to match the 3.50x18" "Super-Akront" rear, isn't exactly forthcoming either -It'll be weird to build my daughter's 'featherweight' DOHC-4 750, "offspring" if you will of my "CB900K0 Bol Bomber", with a MIS-MATCHED pair, Comstar up front & a drum hub wire-spoke wheel on the back - BUT - If I stick to the plan of a DIY dust-bin fairing on that one (huge block of styrofoam and just lay up the glass over TOP of it, smooth it down afterwards with a whole buncha sanding & "surformer" rasping etc etc) it won't be all that obvious what's going on with the front wheel. If it's REALLY well hidden, I suppose I could even throw together another 16"-er just like the Bol Bomber gets (3.50x16" Super-Akront front & 4.25x18" rear, got a spare set of these rims for an eventual SHAFT-DRIVE build, either GL1200 ideally OR perhaps a V65 - ideally a shaft-to-chain conversion, Sabre based "FWS1000" aka RS1000RW "Water Whale" pseudo-replica OR a Magna based "CZ860K0 Sand-Cast" homage to the '60s Czechoslovakian Grand-Prix racer the "Cezeta CZ Type 860" - Down the road it'd be nice to whip up another Czech style Honda from an MVX250F in the vein of a Jawa Type 673 - But even with THOSE temptations hovering in "the mind's eye", it's the GOLD-WING project which beckons me out of the DOHC-4 zone - always has, always will I suppose - The Gold-Wing would be a nice upgrade for me, just let the kid take over the "CB900K0 Bol Bomber", juggle things around - whichever pops up on the local market first I suppose, thought the DOHC-4 750 has a heck of a lot more upgrade parts not just the wire rims themselves but practically a whole bike really, just needs an engine rebuilt - A 'WING on the other hand, same goes for the V65 for that matter, well - just about ANY of these bikes I suppose I'm only looking for a rebuilt or low-mile survivor ENGINE, and a frame - MAYBE a swing-arm on the 'Wing, maybe not?

Well - WHATEVER the next project turns out to be, it's of the Honda four-banger variety - two-smoke triple MVX250F/NS400R hybrid at the very outside edge, CBX if it's landed in my lap - Gotta be a HONDA though, 'cause I'm so fixated on this '80s Honda tech, the COMSTAR wheels the TRAC forks, etc etc.

I suppose the 2.5x18" "Silver" style COMSTAR wheel could be useful on just about ANYTHING which fits that description.

Even if not? I just wanna BUILD the damn thing - as a "Technology Demonstrator" - to take weights and measurements, see how it compares to contemporary racing wheels & wire-spokes etc etc. Maybe throw together a BLOG about that, an APPEAL if you will, to engender support for a new production run of "NERVI" rims in ALL shapes & sizes.... If and when MORAD takes notice, or another suitable rim could be sourced from something else like the Performance Machine "PMFR" composite wheels, what HAVE you - it might just hand on my wall as a piece of ART until a suitable match could be found - But it's still gotta be BUILT in order to get there.




-Sigh.
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