Full Monty rehab. Maybe.

R

Rutabaga

Member
During the last four months and 500 miles I’ve owned this 1976 CT 90 I’ve had three fuses blow. The bike is in great shape but it is 49 years old and the wiring shows that clearly.
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I’ve decided to replace what I can purchase and rehab what is not available and at the same time do maintenance on other components that need some attention. None of this is unexpected and I have purposely run it in order to find any thing that needs attention, which is very little so far.
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I have removed the engine and rear wheel plus all the wiring to the tail area, unbundled the rats nest and the wires running through the main harness. I found the rubber shock transmission inside the rear axle needs replacing, rear brakes are not retracting because the pivot cam is sorta bound up. Going to look at the bushings for the the rear swing arms, etc. Getting a list together as I go along but I’ve done this with several other bikes and vehicles so it doesn’t seem out of scale for a rehab with this sort of aging. Challenges ahead but I’ve been down this path before.
 
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I pulled the rear brakes apart and found they were completely glazed and had a decent amount of brake shoe remaining. I noticed a while back the adjustment screw was almost to the end of its length but the brakes were engaging when the pedal was depressed. In hindsight I should have checked the hub for heat after driving to see if it was dragging. Sanded the drum to rid of the glaze and same for the shoes, I’ll measure the thickness but visually it looks decent. I suspect a previous operator was resting their foot on the pedal and needed to keep adjusting the brake screw rod to try and get any stopping action. May have to replace a bearing or both in the hub, what’s there can no longer be defined as grease. Rubber shocks in the hub are dry rotted. Sprocket inspection is next then swing arm bushings or whatever is holding it place.
 
There's a nice feeling about repairing old parts with minimum outlay and getting them to function properly without doing a restoration of every component.

Restoration is also enjoyable but having the varying levels repair is nice

Keep up the good work!
 
Finished with the rear hub rehab. Sanded the brake pads and drum, removed the oil seal and all bearings for cleaning and inspection. Greased everything requiring it and then zip tied back together until the rubber shock cushions for the drive side arrive in a few days. The bearings were fine but the 49 year old grease was in dire need of replacement years ago. Ordered a wiring harness from Dr Atv and it will be here shortly. Opened up the stator cover to see how far inward I need to go in order to deal with the problem wires where they exit the case to the connector. Can’t really see enough of the exit point of the wires so more case have to come off which probably means more gaskets. Waiting to order that kit til I’m sure it will have all those I need. Changed course and decided to recheck valves and timing while it’s on the bench and easy to see. Valves were a tiny, tiny tight so that is done. Sanded and gapped points but quit before I did timing. IMG_4904.jpegIMG_4901.jpegIMG_4917.jpegIMG_4899.jpeg

I think the rust on top of the points breaker is from a gasket leak and the recent mud removal at the car wash. How does the sprocket look? It’s 45 teeth. The counter sprocket looks good, still square tops and just a little wear. The chain is new so I’ll wait and replace all three at once in the future. Haven’t had the front pads off yet so I don’t know if they are different style but I am seeing some selling certain years with same front and rear pads, other years not so. Anybody used a seller with both front and rear that they could recommend? That black mess in the hub bearing was some tough stuff, and as they always say in F1 racing, that had to be costing me at least 1/10th of a second.
 
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I am interested in replacing four wires coming out from this rubber grommet that originate with the stator. Before I dislodge the grommet is this the best path to achieve that goal or do I need to remove this engine side cover in order to have sufficient room to do the work needed?
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I sort of suspect the wires run directly to the stator coils rather than to an intermediate bus bar or connecting point before exiting to the outside of the case. Anybody been there, done that?
 
Rutabaga said:
View attachment 84558

I am interested in replacing four wires coming out from this rubber grommet that originate with the stator. Before I dislodge the grommet is this the best path to achieve that goal or do I need to remove this engine side cover in order to have sufficient room to do the work needed?
View attachment 84559
I sort of suspect the wires run directly to the stator coils rather than to an intermediate bus bar or connecting point before exiting to the outside of the case. Anybody been there, done that?
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The wires do run directly to the stator coils. If you want a better idea of what that looks like you can find pictures of the stator on ebay.

The biggest problem is those "grommets" are oil sealing. And from what i can tell, honda injection molded the material directly onto the wires. This makes it just about impossible to get new wires on there.

In my opinion, if none of the wires have continuity to ground, don't mess with it. The fabric insulation they used is surprisingly resilient. The neutral light wire not so much, but that's not Mission critical.

Hope that helps, - Kyle
 
Thanks for the guidance. I found some pictures of the stators earlier but hope springs eternal, maybe mine was different.

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These are the types of insulation breeches I am seeing. The material is plastic and very brittle, not a cloth type. Some of the wires in the headlight that have not been exposed to direct sunlight are still flexible and not cracked as these are in the picture. I have thought about trying to individually shrink wrap them but I suspect I will cause more cracks in the process. The only way to get individual cloth or shrink around them (without splitting the wrap the full length to fit over them) would be to remove them from the connector and slide the wrap over the wire ends. However, prying the connector out of the plastic housing has its own perils. My current thought is to try and clean them a bit and see if a hot glue gun would provide some encapsulation of each wire. I like your idea of benign neglect, that is if it doesn’t have continuity to ground don’t bother it. One other method I have entertained is to split the remnants of the black wire bundle covering, separate the individual wires and deal with the one at a time. Another thought is to cut the wires a off at the bare spots and put on new connectors then I could simultaneously slide heat shrink over each wire. ???
 
Thanks. Does the sprocket picture give you any concern? Also had a tip to flip the rear sprocket and run it in the opposite direction. Is that just kicking the can down the road, being cheap?
 
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Got the timing set correctly. Not too surprised by what I found, which was that my eyes are not near as accurate as a test lamp when trying to determine the exact point when contacts open. Looking forward to the next ride with that little oversight corrected. Got some good ideas from comments about the stator wiring dilemma. Currently I am inclined to dyke the wires right behind where the insulation breaks occurred, individually shrink wrap each wire from the stator exit point full length, add new connections and go hunting for other similar spots. I’m also open to any other ideas about the wiring. Got parts enroute; rectifier & wiring harness, rear brake pads, rear hub shock cushions, and another qt. of oil.
Still need to look at swing arm bushings and some other items in the rear.
Was reminiscing this afternoon how some aspects of how I have done these types of projects over the last sixty something years have remained the same, such as using sandpaper a lot, cleaning parts with gasoline and a toothbrush, setting points , etc.
Other aspects that are totally different, such as acquiring parts and the wait time involved. Used to enjoy our parts stores for some items, the hardware store for parts on brands they sold, junk yards and neighbors for the rest of it. The actual acquisition and delivery now is mind boggling. It’s still fun. Just quicker.
 
Rutabaga said:
Finished with the rear hub rehab. Sanded the brake pads and drum, removed the oil seal and all bearings for cleaning and inspection. Greased everything requiring it and then zip tied back together until the rubber shock cushions for the drive side arrive in a few days. The bearings were fine but the 49 year old grease was in dire need of replacement years ago. Ordered a wiring harness from Dr Atv and it will be here shortly. Opened up the stator cover to see how far inward I need to go in order to deal with the problem wires where they exit the case to the connector. Can’t really see enough of the exit point of the wires so more case have to come off which probably means more gaskets. Waiting to order that kit til I’m sure it will have all those I need. Changed course and decided to recheck valves and timing while it’s on the bench and easy to see. Valves were a tiny, tiny tight so that is done. Sanded and gapped points but quit before I did timing. View attachment 84554View attachment 84555View attachment 84556View attachment 84557

I think the rust on top of the points breaker is from a gasket leak and the recent mud removal at the car wash. How does the sprocket look? It’s 45 teeth. The counter sprocket looks good, still square tops and just a little wear. The chain is new so I’ll wait and replace all three at once in the future. Haven’t had the front pads off yet so I don’t know if they are different style but I am seeing some selling certain years with same front and rear pads, other years not so. Anybody used a seller with both front and rear that they could recommend? That black mess in the hub bearing was some tough stuff, and as they always say in F1 racing, that had to be costing me at least 1/10th of a second.
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Looking good so far .

I like to clean, polish then wax the paint when the engine's out .

Those brake shoes look pretty thin to me, they're dirt cheap new and nearly free when purchased / salvaged from other junker Motos .

That rear sprocket is mighty tired, again new ones and chains are good dollar value . I see it has a new chain, this makes replacing that worn out rear sprocket more important because a worn sprocket heavily stresses the chain .

Like you I enjoy bringing these well made machines back to life, rarely necessary to restore them .

I look forward to reading about how good / bad the Dr. ATV's new harness is .

The contact surfaces on the ignition points look good, it you take them apart carefully I bet you can clean up the rust with a scratch brush and re use them, be careful to lot loose the special thin washers .

The brake leves should be set up so its *just* reaching 90 degrees at the pull rod to ensure good easy brakes ~ less than 90 degrees makes them grabby and more than 90 degrees makes them loose power and require more effort .

I too prefer to carefully cut the wires right where they're cracked and solder on new undamaged longer bits then heat shrink .

I buy old scrap harness' and open them to get the *exact* same gauge and thread count wires, then go to town .

That rear sprocket needs to go NOW .

I too somewhat miss those (G)olden days but life is so much better now plus cleaner air and water, so on and so forth .

I wish you'd have detailed how you serviced the hub bearings with pictures and what grease you used etc. .

I'm always learning .

Up to my elbows in a mangled 1971 BMW R75/5 running junker right now, I have high hopes for it .
 
The hub bearings were a surprise ending. IIRC there were three and two had grease black as tar and the consistency of peanut butter. One sounded like it had damage and the other two were gummed up pretty bad. They were fairly easy to tap out once I gently heated the hub area with the heat gun and tapped on them. Cleaned them all with gasoline in a small container until everything was clear. The hesitation in the rolling disappeared and when spun by hand they all sounded and felt good. Oiled them up, finger spun them some more and I feel confident they are more than adequate for a CT 90 axle. I hand packed them with some leftover Lucas Multi “ Red “N” Tacky multi purpose EP grease that has a Drop Point of 540° F, NLGI #2. Truthfully, it was what was in the grease gun from a small camper trailer axle kit. I would have put anything in there for the loads and speeds it will see. Warmed up the hubs again for installation and all went well. Hope the rest of the electrical work goes as smoothly.
Thanks for your thoughts on the sprocket.
 
Is this red grease a full synthetic like boat axle bearing grease ? . or perhaps a Moly based grease ? .

Either way I'm sure it's better than the original stuff you cleaned out .

I have used my small Harbor Fright ultrasonic cleaner to clean bearings and things to very good effect .
 
Rutabaga, if you are set on replacing the wires to the stator these were my thoughts when I was considering it:
-Use a wire with PTFE or other fluorinated hydrocarbon based insulation. These wires won't break down with heat-cycling, oil, or pressure in the same way normal wires do. At work I've seen them repeatedly withstand 4,000 psi of oil pressure at 200 degrees C.
-You can also get PTFE heat-shrink for the connections to the stator.
-I was thinking of re-creating the grommets/seals with gasket maker. I think if you could hold the wires into the engine and make a damn out of cardboard underneath you could basically cast the wires in place with the gasket maker.

I'm very interested to see what you come up with, -Kyle
 
-Nate said:
Is this red grease a full synthetic like boat axle bearing grease ? . or perhaps a Moly based grease ? .

Either way I'm sure it's better than the original stuff you cleaned out .

I have used my small Harbor Fright ultrasonic cleaner to clean bearings and things to very good effect .
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Not sure what it is derived from, Dino or Syn but it is 49 years fresher than what it replaced. I believe it was the recommended grease for the Dexter axle on my Casita camper.
 
I can dig that .

Lubricants have improved -so- much from back in the dayze .

I love Moly based greases for my drive spline applications .

I also have WWII surplus LUBRIPLATE brand "dustless" rifle grease that's fantastic on window lifts and other slow sliding surfaces in dusty environments ~ I have no idea how they made a high pressure grease that isn't sticky on it's surface but it excels in certain applications .
 
Mikerts-Garage said:
Rutabaga, if you are set on replacing the wires to the stator these were my thoughts when I was considering it:
-Use a wire with PTFE or other fluorinated hydrocarbon based insulation. These wires won't break down with heat-cycling, oil, or pressure in the same way normal wires do. At work I've seen them repeatedly withstand 4,000 psi of oil pressure at 200 degrees C.
-You can also get PTFE heat-shrink for the connections to the stator.
-I was thinking of re-creating the grommets/seals with gasket maker. I think if you could hold the wires into the engine and make a damn out of cardboard underneath you could basically cast the wires in place with the gasket maker.

I'm very interested to see what you come up with
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Latest iteration of the stator wiring plan is this; I have removed the connector housing from the wires originating in the stator and separated them from each other by removing the remnants of black plastic sheathing. In order to keep this project from developing “mission creep” I am going to heat shrink each wire the full length (maybe even two layers) and then reassemble the connector, put on some new sheathing of some type around the four wires and call it good. This keeps the project within my skill/ tool/motivation boundaries and keeps me out of a rabbit hole I don’t want to fall in to right now.
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Brakes and rectifier arrived last night so I installed the new pads and found the bearing on that side needed to be seated a little deeper than it was currently. A few taps and everything was back together properly. Awaiting shock cushions for the other side of the hub, should be shortly.
New harness is due soon and will start with the rest of the component wiring, inspecting and mending if needed. I expect to find other insulation breeches, pinches, but I am going to wait for the new harness just to lower the workload of making sure I get things routed and connected properly. So far,🤞🤞🤞it’s been about as expected with this project, significantly because of help from y’all. Thanks.
 
THAT is the MPC I was cautioning about ~ look closely at the male connector blades, I wager they're all green .

This is the part I delete and solder & heat shrink .
 
-Nate said:
THAT is the MPC I was cautioning about ~ look closely at the male connector blades, I wager they're all green .

This is the part I delete and solder & heat shrink .
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I’m not seeing any green from corrosion but there is a patina of age. Now that I have the wires out of the connector frame I can assess how to clean them up. Bought 96” of heat shrink this afternoon from Home Depot and I planning being liberal with its use.
 
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