CB750 rat bike?

pidjones said:
After a GL1000 that had been under water, I'm kind of looking forward to it. The charging system on these is a lot more like an automotive system controlling the field excitation than the GoldWing permanent magnet alternator and regulator that shunts excess to ground. We shall see....

I put a shunt system on mine. A lot easier to deal with. It stays in the 90s here until October, so I was only getting about a year out of the charging system.
If your harness looks bad chuck and replace the whole thing. It’s a pretty cheap replacement. Since you’ve experienced the gold wing wiring, you already know Honda over complicates the crap out of their electrical.


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For those running a shunt type regulator (permanent magnet alternator), let me caution you to NOT rely on the spade connectors for the "three yellow wires". Pull them out of the connector, do a very good solder splice, and cover them with a shrink tube (I like the marine type that Harbor Freight sells with hot glue inside). This joint has been the downfall of many a GL1000, 1100, and 1200. The stator output sees all of the output all of the time on a shunt system, and any oxidation leads to overheating, plastic connector body melting, and eventual shorting of the output which takes out the stator rapidly. I guess it is such a point of emphasis on a GoldWing because the engine has to be pulled to get the stator out.
 
I re-wire all of mine and do away with that connector. Rick's has a write-up about the signal wire on these, which is the cause of the issue, iirc.
 
More fun!

Pulled the front calipers off today and they are headed to the bin. Both pistons frozen SOLID (can't turn with good large channel locks). These look to be CB750F calipers on home-made adapters to the C forks. SO, why not replace with C calipers and dual pistons? Found a pair on ebay already and inquiring if he will combine shipping.
Have the headlight apart and all of the connectors separated. Don't look as bad as the Hunley did, and most are the newer, smaller connections. I'll clean all of them, clean up the handle switches, clean the ignition switch, and splice the main power wire that had a broken crappy spice near the headstock. I don't really mind working on the electrics.
I hate brakes. At least I didn't get brake fluid everywhere, because the system was BONE DRY! All that came out was rust dust. Already have a Chinabay master and I' plan to clean the splitter and buy new lines.
 
I put dual pistons on the front of mine, with steel braided lines. Pretty sure they are off of an 82 or 83 900. They bolted right up. Only thing I don’t like is the wicked nose dive if I break too hard.


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Today the battery got its acid and charge. Reworked the remaining electrical connections, repaired a burnt out fuse position (#1), installed a bypass fuse holder to replace the 30 Amp dogbone. The shim removal tool came in this afternoon, so I was able to pull and measure them all and will work out swap/purchases tomorrow. Last thing was to hook up the battery and a quick test of lights on the dash and tail light with key on, and bump the starter. Tomorrow I hope to get as far as a preliminary compression test. I know clearances are off, but it should reveal major (VERY low compression) issues.
 
Shims on order, oil and filter changed (photo to come), and initial compression test done. MUCH better than I had feared. Was afraid there would be some ~20 psi or even Zero. Lowest dry was 90 psi, but they all went to over 150 with a squirt of oil, which has me hopeful for rings needing loosened up. Pretty amazing considering the spread in valve clearances. Starter cranked happily with no refurb needed. The outboard valve cover bolts had been swapped for standard bolts, so new ones are on order and the inboard bolts all now have new gaskets. BTW, in case it is new to anyone, the trick to geting new gaskets on the bolts undamaged is to soak them in HOT water for about five minutes, then the bolts pop right through them.

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And here is the promised photo. Anybody? Bueller?
 

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Still chasing down what forks they are. CB750 uses 35mm, right? Shoul not have assumed that. Last night I measured (three times). They are 36mm. So, that opens the field a LOT.
 
Howdy - not sure what the question is regarding the oil filter housing, but there should be an o-ring in the groove that runs around the outer perimeter.
 
Also that spring should be on the other side of the filter as well should it not? Pushes filter onto engine just like the gl?
 
Maritime said:
Also that spring should be on the other side of the filter as well should it not? Pushes filter onto engine just like the gl?
Bingo! With the sping like this, all oil bypasses it and on to the engine unfiltered. BTW, the big o-ring was still stuck to the case (guess they didn't coat it with clean oil on installation).
 
I have found that same thing on all 3 of my hondas. The GL was wrong, my CM had no spring installed and the CX was backwards too.
 
Positive (I think) progress this morning. Got the over-tight head bearing preload nut off, and after pulling the stem was able to remove the races from the headstock fairly easily. Helps the I had the tool fromremoving the Hunley's races on hand. It looks like someone had grabbed the stem where it goes through the upper triple with vice grips or a pipe wrench, leaving heavy ridges that scared up the inside of tbe upper triple. I've become pretty good at removing such damage with a single cut mill file, so that is all Ok now. The axle spacer that fis in the right seal was badly pitted. I chucked it in the lathe and took a light cut. If it turns out too small when the new seal comes in, I'll chuck it in the bin and get a new one. Or make one if necessary. Tonight or tomorrow I'll cut the lower bearing off of the stem. This was easy on the GL1000 using a Dremmel and cutting wheel. Hopefully the same here. I kept inner and outer races from yhe GL1000 to use as drivers for installation.

Have settled on the forks being from a Kawasaki KZ750H LTD (probably ~1980). Seals on order.
 
Think I found why they had messed with forks and added a stabilizer. Probably chasing a steering wobble that was in fact caused by the lower stem bearing inner race being seriously damaged. But, that is hard to get off (actually a 10 minute job with a Dremmel), so they did all of this other stuff. At least, that is what I'm hoping. New bearings should be in this week. The outer race looks fine.
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All Ball bearing set in already, as well as valve shims and another set of front calipers. Should keep me busy for most of the week, then the tank and of cource still working the rear caliper to try and get the piston out. Yesterday I turned it some with slip-joint pliers while heating it with a torch. Next, I might try heating while using a new front master pressuring it up.
 
All attempts to save a piston for the one remaining caliper that I need have failed - they were all deeply pitted too much to rescue (finally got them out with the grease gun). So, one is on order and that caliper is cleaned and ready for it. Fork seals came in yesterday, so I installed them in the already-cleaned forks and mounted them up, Also installed a new "GP Touring" handlebar in black. It is very similar to the Euro bar I put on the Hunley, but a tad narrower as I've had problems maneuvering the Hunley in our tight basement.

Today I pulled the carbs (used heat gun to soften the boots). Only did a cursory disassembly by removing a couple float bowls and a couple vacuum domes. Not as good as I'd hoped, but not nearly as bad as I had feared. Fairly sure this bike was last fueled prior to alcohol mandates as rust and varnish is all that I am seeing in the bowls. That varnish however has glued the needles to their seats, so the vacuum piston will not raise. I can rattle it a bit and even move it up and down ~ 1/2 mm, but the needle won't budge. Plans is soaking in carb cleaner to soften and dissolve the varnish so that they release without damage.
 

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A heated ultrasonic will knock most of that out. Most everything else will need to be replaced anyway.

Do those have the press in slow jets?


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