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Discussion Starter #1
Finally starting the build thread - I picked up a free (and free range) CX a few years ago that was missing a handful of parts (no carbs, tach and speedo, etc) After admiring it in my shed for a few years and moving twice, I finally got it running with the assistance of you fine folks and a lot of foolish questions. Now that it runs, Im tearing it back down to the frame, shooting for a quadruple bypass as well as a valve job, the millennial frame hoop chop job, fork and caliper rebuild, and Rae San instal. My goal is to bring this bike back to life so that it can wander for another 30 years. Let the resurrectin' begin.

Not mechanically/electrically savvy, expect mishaps!

First question - I did a compression test prior to tearing down and got 135 in both cylinders, which I know is below spec, since the motor is already dropped should I consider doing piston rings as well? Are there any other things worth inspecting/replacing while the motor is fully disassembled? I was not able to do a leak down test and am hoping the valve job brings cyl. pressure up a little.

**This is a learning project for me so please chime in with any "that was dumb" or "here's a better way to go about it" information, its greatly appreciated.

Cheers yall!

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135 on a cold engine that has not run in many years is OK.
After is has been run a while, the compression may come up to at least 150.
But a true test of the integrity of the engine would be a leak down test.
Your lower reading may be valve seal issue rather than ring seal issue.
Redoing the heads with valve guides and seals and lapping the valves is way less expensive than having to source crank and rod bearings (shells).

I personally would wait on that until you have a chance to ride it some and then test again after at least 100 miles of hard riding.
 

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Discussion Starter #6 (Edited)
Made a little progress tonight. Should I be concerned about the amount of corrosion/gunk in the tubing around the water pump? Any tips on removal/cleaning? I did a white vinegar flush when I initially got the bike, before I changed the coolant and got it running.

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Motor is nearly ready for a deep clean and for me to pull the heads, overall everything appears to be in good enough shape. All bolts and parts are ziplock bagged with labels and notes on installation, Ill still probably muck it up somehow on reassembly.

Now to read about removing stuck fans...I tried pulling it with the front axel as the puller bolt but no luck and I didnt want to damage anything so I hit it with some penetrant and called it a night.

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Clutch cable housing has some gnashes through exposing rusted cable, and the tach cable is severed in the middle. Is it worth replacing the clutch cable or just lubricate the cable and patch the housing?
 

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Replace the clutch cable, both inner and outer.
Get a proper bolt for pulling the fan. Not enough threads on the axle bolt engage with the threads on the fan hub. Usual result is a stripped fan hub.
Why are you planning on pulling the heads? If you do pull the heads use OEM Honda head gaskets. If you must use aftermarket head gaskets be prepared to re-torque the head bolts several times over the first few hundred kilometers (or miles)
 

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Discussion Starter #8
Pulling heads to do a valve job - low compression. The bike was at a point were it ran but had so many projects (leaking fork seals, failed stator, sticking brakes, broken tach cable, etc.) that lined up with me having rented garage space along with some cosmetic/personal changes that I wanted to make, that I opted for the complete rebuild.
 

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The fan mounts to a tapered stud end of the cam shaft and the bolt is torqued to hold it in place but it will stay without one unless there is excessive vibration.
If you are not saving the fan you can use a bearing puller (2 or 3 leg) but you can also use a long shank spark plug (like an old one from the bike) with the electrode removed.
Turn it in till snug and give it a thump with a rubber mallet.
 

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Discussion Starter #11 (Edited)
fan popped with the axle bolt/rubber mallet/super lube combo. First pass at cleaning, still picking at it with simple green and a screwdriver but another hour or two and I think it will be clean enough to pull the heads. I started with a wire brush, should've started with a spatula..

Viton valve stem seals ordered from forum member Genesound, theres a link in his signature if anyone reading this is interested.

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Questions:
Any major downside to painting the motor? Ive read/watched 100 paint prep/paint posts but dont have access to a booth so VHT rattle can for me, which I was hoping to avoid on this build.

Tapered bearings, do it or just re-grease the OG balls?
 

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Discussion Starter #12 (Edited)
A little progress but where the heck did this o-ring come from???? After removing the heads, i set them on my work bench, as I was cleaning up (wrapping them in plastic because I wont be able to work on them until Monday) this little guy was left on the bench. In the parts fiche, it appears to be 91302-044-003 or 91302-GE0-000, not sure why there are two numbers/sizes on the partzilla fiche?
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A little more carbon build up than id hoped..Any tips on cleaning? assuming no wire brush on the piston/head where the new seal will seat? Plan is to soak in gasket remover, have a beer, remove and repeat as necessary
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Heads are free.
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Discussion Starter #14 (Edited)
How clean do you guys get your gasket surfaces? Im trying to balance my OCD for bare polished aluminum with not marring the mating surfaces. Ive been using a flexible razor blade but could soak again in gasket remover? When I removed the heads, the gasket seems to have split in two, attaching to both block and head surfaces equally.

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Spray carb cleaner and a plastic body filler spreader is also helpful to clean that up.
 

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Discussion Starter #18
Will do, thank you guys.

On inspecting the cam chain and guides, it appears to have plenty of life left. I may just replace the stator, o-rings, gaskets, mechanical seal etc and hold off on the guides and cam chain as I dont really see much point in replacing working parts? Now that Im this deep, dropping the motor doesn't seem like such a daunting task any more:p

Ill replace this with better images this weekend but a quick snap on my way to work this am:

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Im running a Rae San hall effect and replacing the G47 with a G8. From the G47 loom, all I need to save is the neutral switch wire right? The core is going to custom rewind.

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Discussion Starter #20
Ive noticed people post tech questions outside of their build threads, is that the best way to do things here?
 
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