Author Topic: The post 70's DOHC Hondas  (Read 3634 times)

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Offline eigenvector

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The post 70's DOHC Hondas
« on: August 24, 2015, 05:18:38 PM »
Past 4 months or so I've been messing with my newest bike - CB750 K Limited.

Just today have it dialed in to the point where it's running well.  The jackass who sold it to me had the coils labeled wrong, so when I replaced the coils I swapped cyl 2 and 4.  I thought this bike was a pig - no power, rode horribly, backfired like a machine gun.  Riding on 2 cylinders - who would have guessed?  Not me apparently...

Finally figured out the coil situation, now I'm on all 4 cylinders ::) but I'm finding that this thing is a barely contained tornado of power.  Dialing in the carbs requires crack precision, idle control knob is best left turn completely out.

I'm fully expecting to wheelie the first time I take it out for reals
Rob
--------------------------------
2018 HD Softail Heritage
1979 CB750K Limited Edition
1977 CB550K
1984 CB700SC Nighthawk
1983 VF750S Sabre

Offline Desert-SOHC

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Re: The post 70's DOHC Hondas
« Reply #1 on: August 24, 2015, 09:15:29 PM »
I had an 82 CB900F that could down right scare you
90 F350 Lariat CS S/C Dually
90 S&S 11SC Cabover Camper
97 FLHTP (under construction)
11 Ranger S/C 2wd

Offline 70CB750

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Re: The post 70's DOHC Hondas
« Reply #2 on: August 25, 2015, 03:26:39 AM »
I had this:



overseas.  93hp, I doubt I ever had it all the way to the end.

Prokop
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I love it when parts come together.

Dorothy - my CB750
CB750K3F - The Red
Sidecar


CB900C

2006 KLR650

Offline ekpent

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Re: The post 70's DOHC Hondas
« Reply #3 on: August 25, 2015, 07:48:10 AM »
 I should get this 900 out at least once this year  ;)

Offline eigenvector

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Re: The post 70's DOHC Hondas
« Reply #4 on: August 25, 2015, 04:27:11 PM »
I have to do surgery on the exhaust system, it's loud enough to get my ears ringing. 

The baffles in them are the worst, I can do better with one hand behind my back.  Feel sorry for my neighbors who surely believe I've changed into one of those 'loud pipes save lives' guy.
Rob
--------------------------------
2018 HD Softail Heritage
1979 CB750K Limited Edition
1977 CB550K
1984 CB700SC Nighthawk
1983 VF750S Sabre

Offline Retro Rocket

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Re: The post 70's DOHC Hondas
« Reply #5 on: August 25, 2015, 04:52:35 PM »
I had this:



overseas.  93hp, I doubt I ever had it all the way to the end.

I had a black one of those, great bike, handled well and very fast, I still have a pile of parts for one, thinking of using them on a hybrid build...
750 K2 1000cc
750 F1 970cc
750 Bitsa 900cc
If You can't fix it with a hammer, You've got an electrical problem.

Offline jas67

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Re: The post 70's DOHC Hondas
« Reply #6 on: August 26, 2015, 05:30:15 PM »
I too am working on a '79 CB750K 10th Anniversary Limited Edition.

When I first got it, it had a good bit of corrosion on both aluminum and chrome parts.    It also had a hideous 18" tall sissy bar + luggage rack combo.    I forgot to take some pictures with this gem on it.

Here it is as it is now, with the proper passenger grab bar ($40 ebay purchase!).

IMG_7332 by jay_snyder67, on Flickr

IMG_7331 by jay_snyder67, on Flickr

Some of the metal parts, before:
IMG_6378 by jay_snyder67, on Flickr

After:
IMG_6379 by jay_snyder67, on Flickr

Before:
IMG_6372 by jay_snyder67, on Flickr

IMG_6377 by jay_snyder67, on Flickr

Before:
IMG_6351 by jay_snyder67, on Flickr
IMG_6353 by jay_snyder67, on Flickr

After:
IMG_6363 by jay_snyder67, on Flickr

It was barely running on 3 cylinders when I got it.    Now that I've cleaned the carbs and adjusted the timing chain tensioners, it's running much better.    I've still got to check the valve clearance and put new plugs in it.    The aftermarket 4-2  mufflers need to be repacked, as they're too loud, and I need to paint the flat black portions of the "Honda" tank badges.
Classic Honda:
1976 CB400F
1975 CB400F (project)
1975 GL1000
1968 CL175 (1 nice one, one project)
1967 CB77
1967 CB160 (2 of 'em, both projects)
1967 CL160 project
Triumph: 2017 Thruxton R
BMW: 2016 R1200RS, 1975 R90S, 1973 R75/5, 1980 R100S
Ducati: 2013  Monster 796, 2013 848 Evo Corse SE track beast, 1974 750GT, 1970 Mk3d 450, 1966 Monza 250
Moto Morini: 1975 (titled 1976) 3 1/2 Strada, w/ Sport clipons.
Moto Guzzi: 2017 V7III Special,  1977 Le Mans, 1974 Eldorado

Offline eigenvector

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Re: The post 70's DOHC Hondas
« Reply #7 on: August 26, 2015, 06:03:00 PM »
I never worry about jazzing them up, too much work and in many ways it's lost on me.  I never wash my commuter bike - but I have to compliment you on the finish, better than the showroom I bet.

The only task I have left on it right now is replacing the front brake hose - plugged and not allowing the piston to return and I have to rebalance the carbs.
Rob
--------------------------------
2018 HD Softail Heritage
1979 CB750K Limited Edition
1977 CB550K
1984 CB700SC Nighthawk
1983 VF750S Sabre

Offline jas67

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Re: The post 70's DOHC Hondas
« Reply #8 on: August 26, 2015, 06:06:54 PM »
I never worry about jazzing them up, too much work and in many ways it's lost on me.  I never wash my commuter bike - but I have to compliment you on the finish, better than the showroom I bet.
Thank you!

The only task I have left on it right now is replacing the front brake hose - plugged and not allowing the piston to return and I have to rebalance the carbs.

Oh yeah, that reminds me, I've got front brake work to do too.   It was missing the caliper, and the master cylinder wasn't pumping any fluid.    So, I got a good-used caliper from ebay, and a new (aftermarket) master cylinder.   I still have to install them, next time I have time to work on it.
Classic Honda:
1976 CB400F
1975 CB400F (project)
1975 GL1000
1968 CL175 (1 nice one, one project)
1967 CB77
1967 CB160 (2 of 'em, both projects)
1967 CL160 project
Triumph: 2017 Thruxton R
BMW: 2016 R1200RS, 1975 R90S, 1973 R75/5, 1980 R100S
Ducati: 2013  Monster 796, 2013 848 Evo Corse SE track beast, 1974 750GT, 1970 Mk3d 450, 1966 Monza 250
Moto Morini: 1975 (titled 1976) 3 1/2 Strada, w/ Sport clipons.
Moto Guzzi: 2017 V7III Special,  1977 Le Mans, 1974 Eldorado

Offline Don R

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Re: The post 70's DOHC Hondas
« Reply #9 on: August 26, 2015, 11:01:38 PM »
 I have an 81 cb900c, 10 speed, the tank and carbs were full of water when I got it. not much rust, it happened shortly before, I cleaned the carbs and put on a vance and hines drag header. I'd like to hear it run tomorrow. And sell it next week.
No matter how many times you paint over a shadow, it's still there.
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Offline 70CB750

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Re: The post 70's DOHC Hondas
« Reply #10 on: August 27, 2015, 04:40:29 AM »
Could I seen this one on ebay not that long ago - like year or two?

Great looking bike, btw.

I too am working on a '79 CB750K 10th Anniversary Limited Edition.

When I first got it, it had a good bit of corrosion on both aluminum and chrome parts.    It also had a hideous 18" tall sissy bar + luggage rack combo.    I forgot to take some pictures with this gem on it.

Here it is as it is now, with the proper passenger grab bar ($40 ebay purchase!).

IMG_7332 by jay_snyder67, on Flickr

IMG_7331 by jay_snyder67, on Flickr

Some of the metal parts, before:
IMG_6378 by jay_snyder67, on Flickr

After:
IMG_6379 by jay_snyder67, on Flickr

Before:
IMG_6372 by jay_snyder67, on Flickr

IMG_6377 by jay_snyder67, on Flickr

Before:
IMG_6351 by jay_snyder67, on Flickr
IMG_6353 by jay_snyder67, on Flickr

After:
IMG_6363 by jay_snyder67, on Flickr

It was barely running on 3 cylinders when I got it.    Now that I've cleaned the carbs and adjusted the timing chain tensioners, it's running much better.    I've still got to check the valve clearance and put new plugs in it.    The aftermarket 4-2  mufflers need to be repacked, as they're too loud, and I need to paint the flat black portions of the "Honda" tank badges.
Prokop
_______________
Pure Gas - find ethanol free gas station near you

I love it when parts come together.

Dorothy - my CB750
CB750K3F - The Red
Sidecar


CB900C

2006 KLR650

Offline jas67

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Re: The post 70's DOHC Hondas
« Reply #11 on: August 27, 2015, 05:20:51 AM »
Could I seen this one on ebay not that long ago - like year or two?

Not this one, but, likely one like it.

This one sat as part of a "collection" for the last 15 years until I was purchased by the guy that I got it from in a private sale.
Classic Honda:
1976 CB400F
1975 CB400F (project)
1975 GL1000
1968 CL175 (1 nice one, one project)
1967 CB77
1967 CB160 (2 of 'em, both projects)
1967 CL160 project
Triumph: 2017 Thruxton R
BMW: 2016 R1200RS, 1975 R90S, 1973 R75/5, 1980 R100S
Ducati: 2013  Monster 796, 2013 848 Evo Corse SE track beast, 1974 750GT, 1970 Mk3d 450, 1966 Monza 250
Moto Morini: 1975 (titled 1976) 3 1/2 Strada, w/ Sport clipons.
Moto Guzzi: 2017 V7III Special,  1977 Le Mans, 1974 Eldorado

Offline 70CB750

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Re: The post 70's DOHC Hondas
« Reply #12 on: August 27, 2015, 05:23:35 AM »
I see  ;D

Honda really outdone herself on these bikes, thery sure are pretty.

Could I seen this one on ebay not that long ago - like year or two?

Not this one, but, likely one like it.

This one sat as part of a "collection" for the last 15 years until I was purchased by the guy that I got it from in a private sale.
Prokop
_______________
Pure Gas - find ethanol free gas station near you

I love it when parts come together.

Dorothy - my CB750
CB750K3F - The Red
Sidecar


CB900C

2006 KLR650

Offline BPellerine

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Re: The post 70's DOHC Hondas
« Reply #13 on: August 27, 2015, 03:20:27 PM »
my buddy bought a 79 new,at the time I had a stock 74 750,it bcame slowww,at that point.bill
1978 CB 750K ard and webers
another anfob