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A friend of mine sold me his 1980 CX500 Deluxe before making a cross-country move, but had already been partway through the engine overhaul so what I've got is a frame with wheels on, a partially assembled engine, and two tubs of miscellaneous parts. At least the teardown is (mostly) done!

To get it running, I've got to:
-Finish cleaning the head that's off, and put it back on
-Replace the alternator stator, install the Rae-San Hall System 12V conversion kit I've got coming from Oz (Still not sure if I can use the original coil packs with it or not, but I've got them!) and reassemble the engine block
-Dissassemble, clean, and rebuild the carbs
-Decide if I want to change plates in the gearbox or not, and reassemble/reattach it
-Rebuild the front brake caliper, change the final drive oil and replace the rear brake pads
-De-rust and repaint the fuel tank
-Replace tires (super dry rotted!)
-Figure out the wiring for and hook up the aftermarket gauge cluster the previous owner had bought, since the stock gauges (included!) are beyond repair - it doesn't seem to have any writing on it of any kind though, and no manual with it either...
-Suspension is still an unknown - it's working well enough that the bike sits correctly, but I have no idea if the fork oil /seals need to be replaced (probably) and haven't had a chance to inspect the rear shocks yet either
-Replace the exhaust system - the H-box is rusted through to the point where it's missing a chunk
-Reassemble everything, including figuring out the lights/cables/turn signals etc

I'd also like to
-Give everything a good clean and polish (I'm a car detailer as my side job, so I'm good at THAT sort of thing!)
-Source and paint side panels
-Redo or restore the seat cover
-Source and apply badges/decals as needed

I'll be taking a year off work starting in September (hopefully) [I work for an airline, and they're providing some once-in-a-lifetime incentives to take some time off] and intend to finish my degree, so the goal is to be able to commute the 10-miles each way or so into campus; I go to Auburn, where motorcycle parking is SIGNIFICANTLY better-located and more available than car parking. If I can graduate in spring, I'd like to take my remaining 3 months off and road-trip it cross country. I'm 25 and might not get this much time off with partial pay again until retirement, so I intend to make the most of it!
 

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Welcome , and enjoy your project, take lots of pictures. Hint! don't hurry, better to pace yourself and do it right the first time then to do it over.
PS be brave and ask many question.
 
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Welcome to the forum and welcome to the world of antique vehicle ownership (they own us, not the other way around). Your bike is 4 decades old and aside from what your friend did the Previous Owners may or may not have done the maintenance necessary to keep it safe & reliable so it is highly recommended to download the Factory Shop Manual for your model (available through the CX Wiki - link in my signature) and go through all of the service procedures, regardless of whether your bike has reached the specified mileage. The FSM will also help you figure out how it goes back together, including drawings of where the cables should be routed.
I also recommend looking on all rubber parts with suspicion because rubber does not age gracefully. You mentioned replacing the ancient tires (should be done anyway if they are over 5 years old no matter how good they look & feel because old rubber simply cannot flow around the irregularities in the asphalt well enough to grip, especially if it is cool or wet) but don't forget things like the rad hoses (both can be cut from a single car heater hose) and the rad cap (rubber valves)(another item best sourced as a car part). If your bike still has the original rubber brake line(s) (should be replaced every 2 or 3 fluid changes = 5 or 6 years) I recommend shopping for modern stainless braided ones (they last practically forever and double the life of the fluid).

  • "Still not sure if I can use the original coil packs with it or not, but I've got them!": Rae-San products are made by forum member Rayman and he is very good about answering questions like that if you contact him through the forum.
  • "Dissassemble, clean, and rebuild the carbs": Larry's carb book (available from forum member LRCXED) is a good reference and many of us have had good results with Randakk's carb kits - expensive but top quality.
Note: If you get your carb kits anywhere else don't use any of the metal parts. The 40 year old originals are probably just fine and the ones included in kits are rarely adequate quality (not to mention often the wrong size).
  • "Decide if I want to change plates in the gearbox or not, and reassemble/reattach it": What exactly do you mean by that? "Gearbox" usually refers to the transmission which is inside the engine, not attached.....
  • "Rebuild the front brake caliper, change the final drive oil and replace the rear brake pads":
--- It is absolutely critical to get the groove where the rings that seal the piston sit surgically clean. Also, don't try to re-use the old rubber parts because even if they seem nice & flexible it is probably much harder than new. This would also be a good time to either replace or rebuild the master cylinder (some replacements cost about the same as a kit) and replace that rubber brake line I mentioned above.
--- Most of us use 80W90 hypoid gear oil (the single grades specified in the manual are hard to find but most places carry 80W90)
--- Examine the original brake pads before you order new ones. They tend to last a long time. It is a good idea to disassemble the brake plate and clean & lube the cam's shaft and the bore it runs in while you are at it.
-De-rust and repaint the fuel tank": If it is particularly bad some have used electrolysis. You might also consider epoxy lining the tank to keep the rust from coming back (most here recommend the POR15 kit but follow the instructions EXACTLY).
  • "Figure out the wiring for and hook up the aftermarket gauge cluster the previous owner had bought, since the stock gauges (included!) are beyond repair - it doesn't seem to have any writing on it of any kind though, and no manual with it either...": Do you know the make & model of the instrument (if not, post a pic and someone may recognize it)?
  • "Suspension is still an unknown - it's working well enough that the bike sits correctly, but I have no idea if the fork oil /seals need to be replaced (probably) and haven't had a chance to inspect the rear shocks yet either": Fork seals aren't expensive. I'd take the opportunity to disassemble them, flush out all the old gunk and make them as good as possible. You might also consider adding preload spacers. BTW, Honda specifies ATF in the forks; Some will recommend a specific grade of proprietary fork oil but I use a 50:50 mix of engine oil and ATF, which allosws you to adjust the viscosity at a much lower cost.
  • "Replace the exhaust system - the H-box is rusted through to the point where it's missing a chunk": If you need mufflers you can usually get original Harley ones from most HD places cheap because so many people have them replaced with louder ones before they take delivery. There are replacements for the H box on the market but most of us use Murray's "Quick Build" mid pipes (available from forum member Murrayf).
  • "Reassemble everything, including figuring out the lights/cables/turn signals etc": The FSM will help with that. While you are in the Wiki get the colour wiring drawing for your model and the Honda Wire Color Codes chart too. And don't be afraid to ask questions.
Oh, and we like pictures so
202517
 

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Discussion Starter #4
To clarify, what I meant on the gearbox was reattach it to its spot on the engine housing. The previous owner removed and partially disassembled it so it needs to go back together and into place. I'll take a couple pictures when I get home of both that and of the aftermarket gauge.

Thank you for the great tips! I was eyeing Murray's aftermarket carb too (though I think it would be cheaper to rebuild). Thanks for the heads up on the metal parts and all the other information! I'll look into the electrolysis thing, the gas tank is pretty bad. The previous owner gave me a bottle of POR15, and luckily I have some 89W90 already (as well as oil and ATF) so that'll save a couple bucks.

Finally, here's a picture the previous owner sent me of the bike before he started tearing it down. Pretty rough!
202518
 

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Make sure the sharp edges of all steel plates face the same way.

You'll see what I mean if you inspect and feel the edges.

They are stamped, one side of the edge is sharp, the other rounded.
 

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Discussion Starter #7
Any ideas for getting a proper torque setting on the small bolts with the engine off the bike? I got them all to around 4 ft-lb before the transmission started rotating around.
 

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Discussion Starter #9
The whole front cover (and back cover) are off.
 

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If you're only torquing the 4 small bolts to 6 - 9 lb just stick a folded rag in the primary drive and let it wind in between the primary drive and clutch gear.

This is bad practice on higher torque bolts like the large special nut behind the lifter plate but 9 lb of torque will hurt nothing here..
 

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I hate to ask ..... but were you winding them all down sequentially moving from one to the other so they went down evenly without loading one more than the other?

I go about 1/3 a turn each. No science. it's one wrist rotation holding the ratchet.

Next question.

Have you broken the bolt - or the clutch post?

Another question.

What size drive on your torque wrench?
 

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There's a fix for that if you search it. It's basically putting a bolt through from the back I think.

Google is your best bet. Tack CX500 forum onto the end of your search term.

You'll now need to remove the clutch special nut and you'll need a better method of preventing rotation.
 

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Discussion Starter #15
Last plate is now dished in. That can't be right, can it? Luckily I have a spare of that at least...
Evenly dished all the way around. I think I need a new torque wrench.
202611
 

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Discussion Starter #18
I think my torque wrench must have failed in some way.
 

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There's a fix for that if you search it. It's basically putting a bolt through from the back I think.

Google is your best bet. Tack CX500 forum onto the end of your search term.

You'll now need to remove the clutch special nut and you'll need a better method of preventing rotation.
See post #16 here Weird clutch problem
 
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Discussion Starter #20
Thanks for your help guys. I was able to get some screws installed in the clutch back plate. I'm buying a new low range torque wrench on Monday.
 
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