I would think a far more useful way to put a matching pair of rims on these bike would be a conversion kit to put a standard wheel of some type onto the SHAFT DRIVE - so that people could use the typical three-spoke mags etc. Or maybe a wire spoked wheel, perhaps the GL1000 gold-wing rear hub would be a good choice. Either a conversion from shaft to chain, or a rear hub conversion to a common rim type....
Not that I'm Dissin' the build that Zero Engineering did! I've loved the twin-sixteen-inch wheel look since the first time I saw it, and I probably noticed theirs before I noticed it on other bikes. Okay, maybe not the old Harleys and Indians etc ... or '90s era 125cc race-bikes etc - but still, I've gotta give those Zero Engineering guys credit for that one.
In fact, I'm sort of ripping off the idea myself. Originally, I wanted to do it with the cheapo chromed steel chopper kit rims they used to sell for CB750 etc - used ones are practically free. But I wrapped my head around the fact that I wanted to build this bike for my lil' GRRL and I justified spending a little extra on the brakes. So instead of the KZ400S drum brake or even single disc, maybe even KZ650 hub with twin rotors etc - I went and got a GT550J four leading shoe drum brake. And then I found some great rims, New-Old-Stock Borrani 3.00x16 & NOS Akront 3.50x16 which was really light. Was using a '75 KZ400 rear hub & NOS belt drive. And one thing that was MOST inspired from the Zero Engineering Virago build was that I was putting all this stuff on the 1980 KZ440LTD! Ha ha. Clip-on bars, dropped front end, flat seat, rear-sets etc - I wonder whether people would recognize it as a cruiser. In a sense, it's become VERY COOL to fix up a neglected Japanese CRUISER. And it's projects like theirs that can take the credit for that. Whenever I see a cruiser based special that's pulled off with more panache' than their "standard" counterparts, it puts a smile on my face. And of course, certain cruisers are more difficult than others. Such as the Virago. Or any other shaft drive bike. The one major break-through which I'd wanna suggest to anybody doing this on a bike that's small enough, light enough etc - was that I was planning to use MAXI-SCOOTER TIRES in 110/70x16 & 140/70x16 - last year Michelin discontinued the DUAL COMPOUND RADIAL of which they had a matched pair in these sizes, but there are still a lot of really cool bias ply AND radial tires available. The only bike I can think of which used the tires and rim sizes of which I selected, was an Aprillia scooter - I think BV250 or BV500 not sure - I figured they're a good match for this KZ440LTD (stripped down of lots of weight, with the plan of going kick-start only with battery eliminator and spragg-clutch removed etc etc) but I'd be hesitant to use 'em on anything much bigger. Which is what makes it special in a way, that it's an idea you could/should/would ONLY do on a smaller bike, that the big fours and litre-bikes just don't get to swim in this pool. Yet it's still the deep end. Yanno?
Alas, just about everything for my 440 project, as well as my long-term DOHC Honda project which was getting the same treatment only with triple DISC wire wheels rather than triple DRUM brakes, and a Borrani flanged rim up front just like the 440 (sorta like a "mini-me" version ha ha) just about everything, more so than the bikes it was the $3000-$4000 worth of parts I'd stockpiled, not to mention all of the hand polished and nail-file modified parts such as home-made "lattice" rear-sets a grid-cut ventillated sprocket cover for the DOHC Honda, re-built polished switch-pots for clip-on handlebars for both bikes, etc etc - endless lists of stuff - I lost it all in a house-fire this past month on March 5th.
But I'm already re-purchasing the same parts. If you're reading this, please don't bid against me on that GT750 drum on eBay! I already put an OBSCENE maximum bid on the thing, so all you're gonna accomplish is jacking up my purchase price. Unless you're putting the same insanely high value on it ... I feel like an ass doing that but I've gotta have some indication that I can re-build, and that 4LS hub is the one part I was worried about replacing - though those NOS rims are also irreplaceable too. I thought the $300 I paid was a lot, I've since heard of the only other NOS Borrani 3.00 x 16 Record rims selling for $650 each in a private sale to a frame up custom bike builder. Probably won't see the Akront in NOS again, though it's on the Triumph Hurricane 900 - the Borrani's on a Guzzi 650 dirt-bike too - they SOUND like '60s parts but they're more like early-'80s to late '90s parts. Though I THINK they both were "available" to chopper builders since the late '60s.... Too much NOS stuff to list, but I'll find it again even if it's used this time 'round I don't care. Other than rims of course, as I need the spoke nipple seats to be as close to new as can be so they can be re-drilled for extra-heavy-duty spokes. That, and they're a bitch to clean up and polish when they're all scratched up. I've done that with other rims, and I think it's worth the money to avoid the extra work involved. Not that NOS rims are necessarily ready to plop on the bike without polishing, powder-clear-coat etc etc.
But yeah, since I'm in the middle of building a Japanese twin Cruiser bike into a Cafe-esque style with sixteen inch rims front and rear, and I've repeatedly said "Please don't steal my idea until I'm finished this build!" - I figured I'd give credit where credit's due and say kudos to you Virago guys, and especially Zero Engineering, for building such an awesome bike! A true original. By far better than the original Yamaha V-twin based cafe/standard. And what's better than that even is the inovative technical solutions in trimming that drum down.
I've often though of these original modified Viragos when thinking of ideas I've had for other spare hubs I had from wheels I bought then didn't use - like KZ650 rear drums etc - I was thinking of large rear hubs like that, and the 4LS Suzuki hub (now an interesting puddle) and how they could make an interesting/innovative part on an electric bike, with rare earth magnets countersunk where the drum linings would be, and windings where the brake shoes are. Some kind of back-up brake would be needed, perhaps a portion of drum lining or magnets IN the linings etc - perhaps only modifying one side of the 4LS type and keep the other stock for back-up. But the modified half would be used for regenerative/recouperative electromagnetic braking. Possibly even as a primary motor in the rear hub or BOTH wheels for two-wheel-drive. It may or may not be an effective brake OR motor, depending on how much could be crammed in there. So again, I might be talking about the biggest of drum brakes being used on the smallest of bikes, simply because bigger EV bikes would need a seperate drive motor and belt drive, with disc brakes and regenerative braking through the drive-train, much like down-shift compression braking.
But yeah, I kept thinking of how those Zero guys milled down the shaft-drive/cush-drive side of the hubs. I've always wondered about two rear drum hubs cut down and welded together for a 4LS front hub too.... Most of 'em are around 180mm, but I put my KZ650CSR hub next to that 4LS GT hub and they appeared to be close, so maybe that's a 190mm drum or larger. Nowhere close to the 250mm & 260mm stuff that's out there - for a couple-three THOUSAND dollars. Cough-cough. But I mean, for the going price of a GT750 hub - a welded up hub from two rear drums would not only have more surface area on it's linings, the flanges could be slightly further apart for a stronger lateral stability - which would be a bonus on say, a side-car rig. It'd be a hassle to construct side-plates with correct geometry and yet light enough to match the weight of the original cast items, but perhaps with some thick billet plate and judicious cross-drilling they'd come close. A whole buncha large holes 90% through in a honeycomb pattern might be as strong as the cast webbing was, maybe even better. There's one case of a welded together rear hub I can think of, where a guy on the Honda DOHC Custom forum put a SOHC rear drum hub onto a spun-down hub from his shaft-drive CB900C - the effect looked very OEM very factory made. The point being, the hub held together under all the power of a hotted-up CB900 motor. Of course, this next time I bring a GT hub in to my machinist to spin down the drums - he'll be curious why I'm back so soon ha ha - I'll have to ask him what it would cost to make a hub just like it from Billet. I wonder about the linings. Bolted/Riveted in, like on Oldani/Grimeca/Fontana Magnesium stuff? Nickasil linings, like you see in modern engine cylinder bores? Gotta wonder. I THINK some of the old iron linings were heat-stretched/freeze-shrunk into place - my melted down example shows that the drums in this particular hub used a series of ridges on the outer circumferences - maybe the linings could be re-used ha ha - pretty sure "Vintage Brake" does re-lining. Shoes at least. Maybe drums too. But yeah, at the prices they're going for, at least somebody's gotta be looking at a replica of the GT hubs. The Fontana/Grimeca etc are getting reproduced now, albeit with original methods and authentically etc - and the Smith-Kanrin is a MODERN version of a drum hub, beautiful and powerful though not "period correct" - there are folks making linkage arms for the Yamaha TZ drums - maybe they'll ALL be available soon. But if a person could sink a lot less money and a lot more time and ingenuity into a composite welded up hub made from the under-valued rear drum brake hubs that are out there, it might just wind up more powerful than any of those other options. I know that your project was intended to produce matched wheels front and rear, given the odd design Yamaha chose - and that a single disc brake was the best way of going about it. But perhaps on a smaller bike, similar methods could be used to produce a dual-sided drum - even with only single-leading-shoe plates on each side, using original rear shoe plates, this would be almost as effective. There's an advantage to the 2LS/4LS brake but it's only a small percentage somewhere in the region of 10-15% and even then only on that one trailing shoe per pair! So it's not as significant as you might think. And of course, so long as the two linings of a dual-sided drum only add up to the width of the lining in a single-sided drum of equivalent diameter, with shoes adding up the same as well - it's the same damned thing, and the dual-sided version only has the advantage of balance and strength in it's casting, with possible weight benefits there-by. (It just LOOKS so freakin' cool!) I figure diameter has gotta be the largest factor, and even then the most important part is how much of that diameter is actually in contact with the shoes themselves, in use when braking. Same as with the swept area of a disc vs the size of brake pads and the caliper's piston diameters and number of pistons. The same caliper on a wider diameter disc is an improvement, true - but a bigger caliper and pad is of greater effect. Same goes for the drums, so those existing rear shoe plates would be just fine. Anyway, the Zero Engineering guys and subsequent Virago customizers went with the disc and that was the totally correct way to go with that build. Me I've caught the "Drum Bug"....
-S.
