CB750 K0/K1 Hybrid

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digger
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Re: CB750 K0/K1 Hybrid

#316

Post by digger »

That looks beautiful, I think you made a wise choice getting the whole package. Can’t wait to see it on the bike and all together.
1975 GL1000
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ritalz
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Re: CB750 K0/K1 Hybrid

#317

Post by ritalz »

Like the color. Are the fork ears normally painted on the 750's?
Al

2003 Goldwing Daily Rider
1975 Goldwing 'Max'
1984 Goldwing New Bagger Project
1976 Goldwing 'Grocery Getter' Sold
1985 Goldwing Interstate 'NCC-1985' sold
1981 Silverwing Sold
1982 Goldeing Project Sold
1981 Goldwing Parted Out
1983 Goldwing Project Sold
1973 CB500F Long Gone
1966 CL77 First Street Bike
http://www.ngwclub.com/gallery3/index.p ... ans/ritalz
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Lucien Harpress
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Re: CB750 K0/K1 Hybrid

#318

Post by Lucien Harpress »

They were up to '71. In '72 they switched to the chrome ears w/ black headlight bucket.
1997 Valkyrie- Light Cutomization, but Too Busy Riding
1980 KZ1300- Bike's Haunted
1976 GL1000 (Yellow)- It Runs (Poorly) and Doesn't Leak (Mostly)
1974 Velosolex 3800- Better Than Walking
1972 CB750- Broke the Chain And Ate the Motor
1969 CT90- The Most Fun You Can Have on 90ccs.
1965 CA77 Dream- Needs a Full Teardown, but Complete

All advice I give is only valid until an expert corrects me.
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Lucien Harpress
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Re: CB750 K0/K1 Hybrid

#319

Post by Lucien Harpress »

In a stunning turn of events, I actually made engine progress today! My head gasket showed up, and decided to finally install the head.

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Because I was a bit paranoid about leaks (and how difficult it would be to fix them), I applied the tiniest film of Three-Bond around the oil return holes (the 8 studs in between the paired cylinders). In '73 I think Honda actually milled out these passages to install rubber gaskets and sleeves to help combat leaks, and as a result had to open up these holes in the head gasket. I did my best to find an early type gasket, but that proved surprisingly difficult, as even the (very expensive) OEM defaults to the later one. I finally settled for a late gasket, but installed a series of (smaller) seals that were actually called out for in a service bulletin back in the 70s. Probably overkill, but again- fixing leaks requires pulling the engine, and the EASIEST way to reinstall the engine involves stripping the frame down all the way.

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The head isn't torqued down all the way yet. Per cfairweather's advice, I'm going to attempt to get a heat cycle in the block via a forced air propane heater before my final torque-down. Because most of the stud nuts are under the valve cover, and you can't removed said cover without, you guessed it, removing the engine.

Still, once that's done I can look at getting the cam sorted, then I'd like to find a way to rig up system that lets me test the oil system on the bench. That way I can make sure the top end is getting oil before I stuff everything in the frame.
1997 Valkyrie- Light Cutomization, but Too Busy Riding
1980 KZ1300- Bike's Haunted
1976 GL1000 (Yellow)- It Runs (Poorly) and Doesn't Leak (Mostly)
1974 Velosolex 3800- Better Than Walking
1972 CB750- Broke the Chain And Ate the Motor
1969 CT90- The Most Fun You Can Have on 90ccs.
1965 CA77 Dream- Needs a Full Teardown, but Complete

All advice I give is only valid until an expert corrects me.
Shadowjack
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Re: CB750 K0/K1 Hybrid

#320

Post by Shadowjack »

I've seen Allen Millyard start a Kaw Z1 engine while it's sitting bare on the tailgate of his pickup to see what it sounded like. No pipes, just carbs and a lashed-together ignition.
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wingrider
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Re: CB750 K0/K1 Hybrid

#321

Post by wingrider »

I would say it wouldn’t be to hard to make that engine run outside of the frame…..
2002 1800 Wing
2001 Valkyrie Interstate
1978 1200 EFI Wing with Motorvation Coupe Royale sidecar
1977 1200 Wing cafe/bobber project
1974 Suzuki GT550
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Lucien Harpress
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Re: CB750 K0/K1 Hybrid

#322

Post by Lucien Harpress »

Been a busy man lately. It started with going out into the garage one night just to drop something off, getting distracted, and accidentally getting the cam in.

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A day or two later I was on a roll, so I got a spare valve cover polished up and installed (the old one leaked pretty badly at the tach drive seal).

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Moving on to other items, an unseasonably warm day let me get at least one can of epoxy primer on to my '71 frame.

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And finally, one of my last trim pieces showed up- (K0-specific) tank badges!

Image
1997 Valkyrie- Light Cutomization, but Too Busy Riding
1980 KZ1300- Bike's Haunted
1976 GL1000 (Yellow)- It Runs (Poorly) and Doesn't Leak (Mostly)
1974 Velosolex 3800- Better Than Walking
1972 CB750- Broke the Chain And Ate the Motor
1969 CT90- The Most Fun You Can Have on 90ccs.
1965 CA77 Dream- Needs a Full Teardown, but Complete

All advice I give is only valid until an expert corrects me.
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Lucien Harpress
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Re: CB750 K0/K1 Hybrid

#323

Post by Lucien Harpress »

Been busy. Another warm(ish) day let me get some paint on the top side of the frame, plus some assorted brackets, most importantly the ones on the airbox.

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I'm waiting on a second can of black to do the undersides, but once that shows up I think I will be very, VERY close to getting the engine in the frame. I think I'm going to replace the wiring harness as well, as while the old one works, it's pretty crusty in places.

In the meantime, I treated myself to a little mockup on my '75 roller.

Image
1997 Valkyrie- Light Cutomization, but Too Busy Riding
1980 KZ1300- Bike's Haunted
1976 GL1000 (Yellow)- It Runs (Poorly) and Doesn't Leak (Mostly)
1974 Velosolex 3800- Better Than Walking
1972 CB750- Broke the Chain And Ate the Motor
1969 CT90- The Most Fun You Can Have on 90ccs.
1965 CA77 Dream- Needs a Full Teardown, but Complete

All advice I give is only valid until an expert corrects me.
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Lucien Harpress
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Re: CB750 K0/K1 Hybrid

#324

Post by Lucien Harpress »

Big day today.

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Next paycheck is getting steering head bearings and rear swingarm bushings, then it's going to be a lot of assembling. Barring something I'm missing that I'm currently forgetting about, that should go quick.
1997 Valkyrie- Light Cutomization, but Too Busy Riding
1980 KZ1300- Bike's Haunted
1976 GL1000 (Yellow)- It Runs (Poorly) and Doesn't Leak (Mostly)
1974 Velosolex 3800- Better Than Walking
1972 CB750- Broke the Chain And Ate the Motor
1969 CT90- The Most Fun You Can Have on 90ccs.
1965 CA77 Dream- Needs a Full Teardown, but Complete

All advice I give is only valid until an expert corrects me.
cfairweather
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Re: CB750 K0/K1 Hybrid

#325

Post by cfairweather »

Now that looks like progress. Do you have new oil lines? I can help you make a set if needed.
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Jonesz
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Re: CB750 K0/K1 Hybrid

#326

Post by Jonesz »

I am thinkin that you are going to have one gorgeous bike.
Jonesz

1983 GL1100 Aspencade named "Freki" currently undergoing change to a standard. Sold
1999 Valkyrie CT 1500 goes by the moniker "Valerie"
1978 Gl1000 "Loki" new project going to be a Cafe Convertible
1979 Suzuki GS850. Sold
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Lucien Harpress
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Re: CB750 K0/K1 Hybrid

#327

Post by Lucien Harpress »

Thanks. I should be good on oil lines. Between the set on the bike and the spare oil tank or two, I think I have like three sets kicking around the garage. And if I do need to go to a new set, they're easy enough to get to.

I went ahead and got a new wiring harness as well, but I don't want to get too crazy installing stuff until I get the centerstand swapped over. That'll give me a bit more of a stable base to start moving parts over.

I think the only other big-ticket requirement I still need to get is an early set of left-hand controls. My current setup includes a turn signal buzzer, and the left controls on the K2 had a cancel button if you wanted to quiet it down. The K0/K1 didn't have a buzzer, so the controls are a bit different. I could probably re-use mine, but the clutch lever mount it bent, and I question how good the internal contacts are. I've already had to replace the right controls, so may as well match them.
1997 Valkyrie- Light Cutomization, but Too Busy Riding
1980 KZ1300- Bike's Haunted
1976 GL1000 (Yellow)- It Runs (Poorly) and Doesn't Leak (Mostly)
1974 Velosolex 3800- Better Than Walking
1972 CB750- Broke the Chain And Ate the Motor
1969 CT90- The Most Fun You Can Have on 90ccs.
1965 CA77 Dream- Needs a Full Teardown, but Complete

All advice I give is only valid until an expert corrects me.
cfairweather
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Re: CB750 K0/K1 Hybrid

#328

Post by cfairweather »

Unless you got a genuine Honda wiring harness, you need to cut it open and solder every connection. Trust me, I have used a half dozen of the third party wiring harnesses and you will experience intermittent connection issues if you do not solder the wires. You will find about 10 connections that they twisted together. Once you solder the wires, the harness is fine.
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Lucien Harpress
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Re: CB750 K0/K1 Hybrid

#329

Post by Lucien Harpress »

Whelp, we hit a potential snag.

Image

I'm gearing up to do the swingarm and triple tree, and I got to looking at what I had, and noticed that the gap around the top of the right fork didn't match the left. Sure enough, we have the beginnings of a stress crack.

Far as I can figure, this is a common problem with early top triple tree clamps on the '69-'72 750s. The downside is that this means non-cracked units start at about $300. Welding is an option, but I've heard mixed things about getting that done (ranging from not being able to trust the repair to the clamp being made of a low-quality alloy that doesn't really weld well in the first place). Finally, Yamiya, the place where I got my body panels, sells new reproduction clamps for about $160 plus shipping.

Not sure how I'm going to tackle this quite yet. I just know this was an expensive crack.
1997 Valkyrie- Light Cutomization, but Too Busy Riding
1980 KZ1300- Bike's Haunted
1976 GL1000 (Yellow)- It Runs (Poorly) and Doesn't Leak (Mostly)
1974 Velosolex 3800- Better Than Walking
1972 CB750- Broke the Chain And Ate the Motor
1969 CT90- The Most Fun You Can Have on 90ccs.
1965 CA77 Dream- Needs a Full Teardown, but Complete

All advice I give is only valid until an expert corrects me.
cfairweather
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Location: Cheyenne, Wyoming

Re: CB750 K0/K1 Hybrid

#330

Post by cfairweather »

In my opinion, this is an unrepairable crack. Yes, this happens a lot because people tighten the clamp without first inserting the special washer that goes in the crack. I have a couple of new washers if you can't find them. You must use the washer or this will happen. David Silver spares has one new part for $300.00 + 20 shipping so it looks like Yamiya is the best place.
https://www.davidsilverspares.com/CB750 ... rt_229181/
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