So anyway, here's the post where I try to detail the project, for those of you who are contemplating it yourselves.
1) Part gathering: Mostly Ebay. Just spent a few months collecting '75-'76 GL1000 Goldwing bits including a front wheel, forks, triple clamp, and brake calipers. Bought a bunch of individual pieces rather than a whole front end as I was trying to save some money. Kind of ended up regretting it as I ended up having to buy some extra bits and just generally spending time and money figuring out what little things I needed like axle spacers, etc.
I also bought parts from various stores, including Ebay stores. I bought some new chrome clip-ons (37 MM), a used '97 VFR master cylinder, a new set of braided stainless lines for a '99 CBR1000, and a universal clutch perch/lever and push/pull throttle.
2)Preparation: so now we all know you have to have the clamp stem swapped. Grind off the welds from the bottom of the clamps, have the shop press out the stems and press the 500 stem into the GL clamp. (Apparently this requires at least a 12 ton hydraulic press. Don't bother going at it with the mallet. It won't work.) It may be possible to then use the clamp stem as-is, ie. no welding. For peace of mind I went ahead and had it welded back up.
There was also the trouble with the top clamp that I mentioned in an earlier post: the stock top clamps come with like 2.5" risers for the bars. As I intended to use clip-ons, I cut the risers off with an air tool only to leave a pair of big holes in the clamps. I ended up cutting out some aluminum covers to match the teardrop-shaped holes and JB welding them into place. This is an okay fix cosmetically, but fair warning: if you cut the riser clamps off too close to the surface of the top clamp, you're going to run into the cuts Honda made so that the fork clamps can be tightened. Then you get to go shop for another top clamp.
Beyond that, I simply did some cosmetic stuff like spray painting the clamps themselves, bead blasting the fork lowers, rebuilding the brake calipers, and cleaning, polishing, and touching up the head tube while it was accessible. This would have been a perfect time to replace the steering bearings with something fancy, but I'm 1) broke and 2) impatient. So after inspecting the original items I saw no reason not to reuse them.
3) Assembly: Mostly straightforward, but it was necessary to unplug some electrics in the rat's nest in the headlight bucket in order to get all of the wires out and the bucket off. I had a big flat cardboard box in the garage and I used it to gather and separate parts and also to make notes to myself about electrics. After the minor disaster with the triple clamp, things went back together easily. I used the original bearings and races after a thorough cleaning with gas. (I know, I know.) A thick layer of heavy grease in the lower bearing cup holds the loose ball bearings long enough to get them all in and the clamp assembled. You will need a hook-type tool to adjust the top bearing cup. A hammer and punch will work, but WILL eff up the adjusting slots. FWIW, you can use either the original CB500 chrome cap to clamp down the top clamp, or the hollow one that is used on the GL1000. The GL item requires the same hook tool for adjustment. Using the punch and hammer will make an ugly mess out of it.
Next come the fork tubes, which are 2.5 inches longer than the CB500 tubes. I cut one inch off the springs with an air tool and used an angle grinder to grind new flats into the top of the springs. Then I raised the tubes one inch above the top clamp, meaning that the front end now rides half an inch higher than it used to. (2.5 minus 1 minus 1 equals 0.5). I cannot see the difference in the way the bike sits, but the handling has slowed down just a touch. I plan on solving this by later going to an 18 inch front wheel. So far I have not noticed any ill effects from shortening the springs, but I have only ridden the bike for 30 minutes. Problems may still crop up. BTW, the GL1000 forks call for 200 cc's of 15 weight fork oil per tube. Also, if you buy tubes from Ebay, make sure you get the bottom axle clamps. A surprising number of the Ebay forks I saw didn't include the axle clamps, and I had to go searching for them after the forks arrived. (Ended up buying another set of forks as I found a pair for $25 including shipping, which is no more expensive than clamps themselves.)
I fitted up the controls next. (Remember to slide the clip-ons onto the fork tubes before running them into the top clamp! Unless, of course, you intend to affix the clip-ons to the extended portion of the tubes above the clamp, which then obviates the need to shorten springs...) As I'm running the bike kick-only, no horn or turn signals, and as the new handlebar position makes mirrors utterly useless, I elected to ditch all of the stock controls and fit aftermarket stuff. Most dirt bike shops carry simple clutch perch/levers with or without mirror mounts. These bolt right up but are a bit junky. I broke the first perch by overtightening and had to shell out another five bucks. A bit of creative clutch cable routing is also called for, but isn't too difficult.
I fitted up the VFR master cylinder. I can't get it in exactly the right position as the reservoir interferes with the fork tubes. In order to rotate it down enough for the lever to be in a comfortable position, the whole thing has to be slid down the bar (outward) until the end of the lever sits far past the end of the bar. I compromised between perfect fit and decent looks. I really should have waited until a remote reservoir master came up on Ebay, but after a month I'd seen nothing under $100. The brand new brake lines fitted perfectly and came with a set of banjo bolts and washers, also for the CBR1000. No problems at all there, although again, you have to fool around with routing until you're happy. The VFR master, BTW, has a pair of male blade connectors for hooking up the brake light. I haven't done it yet, but Radio Shack carries the appropriate female sockets and a bit of soldering should get it sorted. I've been using a banjo bolt with a switch built in, but the added internal space makes bleeding a bit trickier and reduces feel just a touch, IMO. I mention this stuff because I bypassed all the intermediate hose/brake switch junk when I bought the bike. Just two lines directly from the master to the calipers, so you have to figure out a way to activate the brake light.
I replaced the throttle with a universal push/pull from the motocross shop. Splicing out the headlight controls is simple. On the 500 at any rate, the headlamp just needs the green (ground) wire plugged directly in to the green wire in the rat's nest, and the white into the black with white stripe multiple connector. This results in "low" whenever the ignition switch is in the run position. If you want "high", just substitute the blue for the white. I briefly toyed with the idea of installing a switch in the headlight bucket, which would have been very straightforward, but in my neighborhood there is simply no use for the high beam. Bypassing the ignition cutoff is equally easy. Black to black/white. (BTW, if your bike isn't running perfectly, check your cutoff switch. I had suspected it was causing some troubles and bypassing it proved me right. I had a slight miss at idle that is now gone. As that was the last remaining imperfection in the way the bike ran, I couldn't be happier.) At any rate, the universal throttle is compatible with the existing cables and was easy. Just a bit of fiddling with positioning and figuring out which cable goes where (it won't let you hook it up incorrectly) and you're in business.
The brake calipers are standard GL1000 items. Make sure that when you get them they come with the aluminum mounting brackets; they aren't as simple as CB500 brakes and won't mount up without the brackets. I notice about half of the calipers on Ebay don't come with brackets, and I saw one Ebay seller answering a question about his bracketless calipers by claiming that there are no brackets, never were any brackets, and don't need any brackets. Caveat emptor. The calipers I got needed rebuilding (Count on having to rebuild ANY calipers you buy from Ebay, IMO) but all the original parts were functional, just filthy. As I say, the GL calipers ARE more complicated than the SOHC items, but not terribly so. Make notes as you take them apart and they'll go back together again without difficulty.
Okay, now the front wheel, which is kind of a #$%*. It's still a 19 inch rim of essentially the same width as the CB500, but it's a nice D.I.D. alloy job instead of the nasty chrome. Make SURE when you buy the axle -- whether it comes with the wheel or not -- that it comes with the little half inch spacer. Mine didn't -- most of them don't, if you're buying from Ebay -- and you'll want it. FWIW, the axle is a three piece affair: the axle with the right side clamping section as one piece, the left side clamping piece/area which threads on, and the little spacer. You will also need the speedo gearbox if you're going to run the stock speedo. I have no idea if it's compatible with the SOHC speedos but I don't think the SOHC gearbox fits either. You may want to buy a GL1000 speedo if you like analog. I bypassed the whole sorry mess by running a bicycle computer, which presented a problem in that the gearbox is part of the axle spacing system. I bought a short length of galvanized water pipe from Home Depot -- half inch I.D.? -- and made some spacers out of it with a hack saw and my angle grinder. FWIW, if you go sans gearbox, you'll need the stock right side spacer with an additional .250" spacer, and a .400" spacer for the left side. If you don't feel like fussing with homemade spacers,you could probably use stacked washers, but it won't look very neat, IMO.
Bleeding the brake system was a bit difficult. I used a mighty-vac tool to pull fluid from the resevoir down the lines and into the calipers, and it seemd to take forever. Never got to the point where I wasn't pulling air from the lines. Eventually quit and tried bleeding the old fashioned way, opening and closing the bleed screw in synch with squeezing the brake lever. This seemed to reveal no air in the system, so WTF? At any rate, the lever pull comes up fairly hard; harder than stock for sure, but probably not as good as on a modern bike. Dunno if this has to do with the old-tech GL calipers or the possibility of air still in the system. And to be honest, I'm not sure I'm getting as much pad retraction as I'd like: there's a bit of pad drag and with 50 HP on tap, I'm not thrilled. I think there's still air in there somewhere. And it may be that the VFR master isn't perfectly happy with the GL calipers. More experimentation is in order.
I attached the headlight bucket with universal chrome arms from J.C. Whitney. As the new forks are spread a bit wider than the old, it was necessary to use stacked washers to get the fit right, but the stock bolts in the bucket worked fine. The stock gauges don't fit with the CB500 mounting plate, and I didn't buy the GL1000 plate, assuming there is such a thing. There are two mounting holes on the GL clamp; I used a chrome steel plate that came from a J.C. Whitney tach to mount up the CB500 tach. The other hole is empty thanks to my bicycle speedometer.
I haven't fitted the front fender yet. I'm using a fiberglass CR750 fender from AirTech and it won't fit the GL forks. I bent the stock CB500 bracket to make it wider, which seemed like it would work until I realized that it was now too low/close to the tire. Will either look into a GL1000 mount or just fab something up out of sheet. It may be my imagination, but I think handling is a tad spooky without that mount acting as a brace.
And I think that was it. I've tried to be thorough, but may have missed something while writing this. Be glad to answer any questions.
Parts list (including shipping unless noted):
Forks: $35, Ebay.
Triple clamp: $15, Ebay.
Front wheel w/tire: $20, Ebay. (No shipping, local pick-up. Shipping's a #$%* on bulky stuff.)
Calipers: $25, Ebay. (This was a screaming deal; most of the calipers I saw went for 50 bucks minimum, and some of those looked like hell even in the little tiny pics.)
Aftermarket throttle: $25.
Aftermarket clutch perch and lever: $11.
VFR brake master: $40, Ebay. Another good deal as decent masters seem to go past $75 and even $100.
NOS chrome steel clip-ons, 37mm: $50. Expensive, but half the price of everything I saw except crashed old junk.
New Galfer braided lines for CBR1000, including banjo bolts and crush washers: $40. Another screaming deal, as this stuff retails for like $120. "Buy it now" for $40 including shipping; don't ask me why.
Miscellaneous crap like spray paint, tubing for making spacers, etc.: maybe $25.
Charge for pressing out and pressing in steering stems: $40. Probably less if you live, well, pretty much anywhere else in the country.
Charge for welding: $25. Ditto.
Labor: probably 15 hours, not including the down time waiting for the aforementioned pressing/welding, or the months of collecting parts.
Total: $325 plus whatever I pretend my time is worth.
Worth it? Maybe. The brakes are definitely several hundred percent better. The handling, well, I don't know. I like the Ducatiesque stability and turn tracking ability, but I do think that the lack of a fork brace has made things a little wobbly. Assuming the fender mount/brace can be done without too much trouble and improves the handling, then yeah, I'll be very glad to have done the project.
Hope this all helps!
