Author Topic: 1971 CB750 Project with lots of photos  (Read 1394 times)

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Offline cfairweather

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1971 CB750 Project with lots of photos
« on: April 13, 2020, 08:12:33 AM »
This is a work in progress but I can see the light at the end of the tunnel.  I will make another post when it it is finished.
I decided to move the pictures to my Google drive for people to view.  I live in Cheyenne WY and bought this bike from a man in Leadville CO for about $500.00 and it will be the last CB750 that I will restore.  It just costs too much to restore the CB750 Honda.  This one must have been sitting outside for decades as I have never had a project bike so hard to disassemble.  It was like everything had fused together.  I had a lot of trouble dealing with one large main bearing bolt that snapped off in the block.  Had to drill it out and repair it, but I am confident this is like new again.  Some of the parts were beyond repair like the seat.  It was in the worst condition of any bike I have restored and many people would have junked it.  I rebuilt the original engine with parts from a low mileage wrecked 1975 CB750F engine.  This engine had a hole in the side and water damage in one cylinder but the lower end was in amazing condition.  I cleaned up the original head and sent it to a motorcycle machine shop in Oregon and they rebuilt it.  I was glad to replace the 1971 engine parts with ones from a 1975 model because Honda made several improvements over time.  I installed new pistons, cam chain, primary chains, seals and used a R2 cam from a 1972 CB750.  The earlier cams were hotter than the later and I had several to choose from in my pile.  I also used heavy duty studs which was one of the weak components in the engine design.  I used my ultrasonic cleaner to clean the cases so it was spotless when it went back together.  I rebuilt the gauges and set the odometer to 0000.  The tank was in bad shape and my brother supplied one in good condition.  The carbs were completely stuck and had to be soaked for days to get anything to move.  Everything was difficult.  I bought a new swing arm off of eBay and rebuilt it with new bearings.  I had the tail light bracket re-chromed and bought new fenders. to make it look great again.  New no number pipes (HM300) for this bike cost me $1600.00 plus shipping.   

Here are a few more details but I cannot begin to tell you everything as this bike has taken a lot of time and money. 
 
1.  Wheels:  I installed new spokes, rims, wheel bearings, brakes, tires and other components to make them like new. 
2.  Frame:  cleaned, sanded and painted. 
3.  New handlebars with new controls.
4.  I made several parts with my 3D printer and they worked great.
5.  New wiring  harness and I disassembled it to solder all connections.  They make them poorly and only crimp the wires together so it is best to solder everything.  Very time consuming.
6.  New chain and sprockets.
7.  New cables.
8.  New clutch plates.
9.  New electronic ignition,spark plug wires and coils.
10. All new electronic components.
11.  New seat foam and cover. 
12.  I rebuilt the foot pegs.
 
Ok, finally the link to the pictures. 
Cedric

https://drive.google.com/open?id=1bxVILi_SZf969Q5d_lGNY4AEUpjeQbbJ

Offline BenelliSEI

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Re: 1971 CB750 Project with lots of photos
« Reply #1 on: April 13, 2020, 05:10:59 PM »
Cedric...... huge task, well done. How long did it take? Congrats!

Offline cfairweather

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Re: 1971 CB750 Project with lots of photos
« Reply #2 on: April 14, 2020, 12:32:04 PM »
Thank you.  I have been working on this bike for several months and still have about a month more of work before it will be done.  I just work on it a bit each day as this is a hobby for me.  Today, I discovered the Dyna Electronic unit was faulty out of the box so I have decided to try HondaMan's Transistor Ignition.  I placed an order for one this morning.  For now, I will go back to points and try to start the bike in a few days.    I have used Dyna units on many of my projects and have never had any issue, but this one had a bad module.

Offline cfairweather

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Re: 1971 CB750 Project with lots of photos
« Reply #3 on: April 28, 2020, 01:57:44 PM »
The 1971 CB750 K1 project is complete and here is the result.  See the below link for many pictures that show the original bike and the restoration process. 

Pictures from beginning to end...
https://drive.google.com/open?id=1bxVILi_SZf969Q5d_lGNY4AEUpjeQbbJ



Offline SOHC4 Cafe Racer Fan

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Re: 1971 CB750 Project with lots of photos
« Reply #4 on: April 28, 2020, 06:09:37 PM »
Nominated for Bike of the Month:  http://forums.sohc4.net/index.php/topic,180400.0.html

Anyone want to "second" the nomination (other than cfairweather), please do it to the nomination thread.
1975 CB550K1 "Blue" Stockish Restomod (http://forums.sohc4.net/index.php?topic=135005.0)
1975 CB550F1 frame/CB650 engine hybrid "The Hot Mess" (http://forums.sohc4.net/index.php/topic,150220.0.html)
2008 Triumph Thruxton (http://forums.sohc4.net/index.php/topic,190956.0.html)
2014 MV Agusta Brutale Dragster 800
2015 Yamaha FZ-09 (http://forums.sohc4.net/index.php/topic,186861.0.html)

"There are some things nobody needs in this world, and a bright-red, hunch-back, warp-speed 900cc cafe racer is one of them — but I want one anyway, and on some days I actually believe I need one.... Being shot out of a cannon will always be better than being squeezed out of a tube. That is why God made fast motorcycles, Bubba." Hunter S. Thompson, Song of the Sausage Creature, Cycle World, March 1995.  (http://www.latexnet.org/~csmith/sausage.html and https://magazine.cycleworld.com/article/1995/3/1/song-of-the-sausage-creature)

Sold/Emeritus
1973 CB750K2 "Bionic Mongrel" (http://forums.sohc4.net/index.php?topic=132734.0) - Sold
1977 CB750K7 "Nine Lives" Restomod (http://forums.sohc4.net/index.php?topic=50490.0) - Sold
2005 RVT1000RR RC51-SP2 "El Diablo" - Sold
2016+ Triumph Thruxton 1200 R (http://forums.sohc4.net/index.php/topic,170198.0.html) - Sold

Offline cfairweather

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Re: 1971 CB750 Project with lots of photos
« Reply #5 on: April 30, 2020, 03:20:02 AM »
Thanks for nominating my bike for BOM. Cedric

Offline Prospect

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Re: 1971 CB750 Project with lots of photos
« Reply #6 on: April 30, 2020, 11:24:26 AM »
Excellent job considering the initial state of the bike. 
Current Bikes

1969 CB750  Sandcast #256
1971 CB750K1
1972 CB750K1
1975 CB400F
1975 GL1000 Goldwing
1954 Harley Davidson Panhead
1957 Harley Davidson Panhead

Toronto Canada

Offline Stev-o

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Re: 1971 CB750 Project with lots of photos
« Reply #7 on: April 30, 2020, 01:59:21 PM »
Nominated for Bike of the Month:  http://forums.sohc4.net/index.php/topic,180400.0.html

Anyone want to "second" the nomination (other than cfairweather), please do it to the nomination thread.

Seconded!

Gorgeous bike cfair.

BTW - if you think restoring a CB750 is expensive, dont ever buy a Kawasaki H2!
'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

Offline SOHC4 Cafe Racer Fan

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Re: 1971 CB750 Project with lots of photos
« Reply #8 on: May 01, 2020, 08:53:35 AM »
Thanks for nominating my bike for BOM. Cedric

Cedric,

Your CB750 has been nominated and seconded.  To accept the nomination, please post that you "accept" in the nomination thread:  http://forums.sohc4.net/index.php/topic,180400.0.html
1975 CB550K1 "Blue" Stockish Restomod (http://forums.sohc4.net/index.php?topic=135005.0)
1975 CB550F1 frame/CB650 engine hybrid "The Hot Mess" (http://forums.sohc4.net/index.php/topic,150220.0.html)
2008 Triumph Thruxton (http://forums.sohc4.net/index.php/topic,190956.0.html)
2014 MV Agusta Brutale Dragster 800
2015 Yamaha FZ-09 (http://forums.sohc4.net/index.php/topic,186861.0.html)

"There are some things nobody needs in this world, and a bright-red, hunch-back, warp-speed 900cc cafe racer is one of them — but I want one anyway, and on some days I actually believe I need one.... Being shot out of a cannon will always be better than being squeezed out of a tube. That is why God made fast motorcycles, Bubba." Hunter S. Thompson, Song of the Sausage Creature, Cycle World, March 1995.  (http://www.latexnet.org/~csmith/sausage.html and https://magazine.cycleworld.com/article/1995/3/1/song-of-the-sausage-creature)

Sold/Emeritus
1973 CB750K2 "Bionic Mongrel" (http://forums.sohc4.net/index.php?topic=132734.0) - Sold
1977 CB750K7 "Nine Lives" Restomod (http://forums.sohc4.net/index.php?topic=50490.0) - Sold
2005 RVT1000RR RC51-SP2 "El Diablo" - Sold
2016+ Triumph Thruxton 1200 R (http://forums.sohc4.net/index.php/topic,170198.0.html) - Sold