Author Topic: 1978 750F The start of a big project.  (Read 15871 times)

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Offline Jnel

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Re: 1978 750F The start of a big project.
« Reply #125 on: August 20, 2017, 11:58:03 AM »
I air photoshoped that out.  You noticed the seat no dought.

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Offline Jnel

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Re: 1978 750F The start of a big project.
« Reply #126 on: August 20, 2017, 12:06:06 PM »
I went with the shorter Delkevic muffler for that reason. Picture is in the Reunion blog if interested. We gassed up the freshly installed Weber carbs through the 2 open fuel lines without installing the tank just to see if it would fire with the Webers. I didn't have it running enough to truely judge whether I like the sound or not. It is quieter than I expected after spoking with the Delkevic guy but that is an easy fix.  ;D Ofreen should be posting up a first firing video soon.
Im ok with a little on the quiet side.  I also ride a 15 ultra classic and it has stock exhaust.  I take a razzing over that.  What can i say.... i like to be able to hear stuff and not have it blown out by the pipes. I feel in love with the 4 into 4 stock pipes on my first 72 750.  Its one of the reasons i bought the bike back then.  But i can pull some of the baffels if i feel the need.

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Offline Mike-Quebec

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Re: 1978 750F The start of a big project.
« Reply #127 on: August 24, 2017, 06:20:39 AM »
Great progress! Looking good so far! That's some inspiration for my cb750F 1975's rebuild!!

Offline Jnel

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Re: 1978 750F The start of a big project.
« Reply #128 on: August 24, 2017, 07:48:02 AM »
After and before.   I was not in love with the locking lid on the F seres.  Decided to remove it.  I put in the new bung and metal.  Welded it all in.  What a pain.  Im not showing the weld job.  Cal....  not showing the weld job!

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Offline Jnel

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Re: 1978 750F The start of a big project.
« Reply #129 on: August 24, 2017, 07:58:33 AM »
Oh yes... i blasted the inside.  Very easy on that.  That stuff is so thin.  I used this stuff for 24 hours.  Did a great job.  I used 1 gallon and kept rolling it around.  For some reason i think it worked better when there was more air in the tank.  It looked almost new.  But... i fould a bunch of pin holes.  Mostly at the seams.  That was fun.  More welding. 

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Offline SOHC4 Cafe Racer Fan

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Re: 1978 750F The start of a big project.
« Reply #130 on: August 24, 2017, 08:49:20 AM »
What thickness steel did you use to cover the hole and mount the bung?
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 calj737

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Re: 1978 750F The start of a big project.
« Reply #131 on: August 24, 2017, 09:24:25 AM »
To weld up the pinholes, use Silicon Bronze wire. It welds at a lower temp (brazing) and works great for tank work and body work.
'74 550 Build http://forums.sohc4.net/index.php?topic=126401.0
'73 500 Build http://forums.sohc4.net/index.php?topic=132935.0

"Of all tyrannies, a tyranny sincerely exercised for the good of it's victim may be the most oppressive. It may be better to live under robber barons than under omnipotent moral busybodies. The robber baron's cruelty may sometimes sleep, his cupidity may at some point be satiated, but those who torment us for our own good will torment us without end for they do so with the approval of their own conscience." - C.S. Lewis

Offline SOHC4 Cafe Racer Fan

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Re: 1978 750F The start of a big project.
« Reply #132 on: August 24, 2017, 10:04:44 AM »
To weld up the pinholes, use Silicon Bronze wire. It welds at a lower temp (brazing) and works great for tank work and body work.

Cal,

When my SS tank had pinholes, my metal fab guy welded patches (because there were so many pinholes concentrated in areas of the tank.  How does Brazing work.  Is using the wires a higher temperature version of soldering to fill the holes?
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 Jnel

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Re: 1978 750F The start of a big project.
« Reply #133 on: August 24, 2017, 10:33:22 AM »
What thickness steel did you use to cover the hole and mount the bung?
I used the same thickness as the tank. .040.  I gas welded it, thinking the same size metal would be better for heating and less distortion. Even tho, the tank metal was effected more then i care to admit.  The old Japanese was doing some tricks and it was a difficult job.  Hense... no photos.  No proud of the job.  But it passed the leak test.

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Offline SOHC4 Cafe Racer Fan

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Re: 1978 750F The start of a big project.
« Reply #134 on: August 24, 2017, 12:35:35 PM »
No leaks, looks straight primed, functional.  What's not to like? Apparently, nothing a grinder and some filler couldn't sort out.
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 calj737

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Re: 1978 750F The start of a big project.
« Reply #135 on: August 24, 2017, 12:42:08 PM »
Yes, Don, silicon bronze wire melts at a lower temp than carbon steel. It's not as strong as a weld, but it is darn strong and perfect filler for body work. Another benefit is it's not corrosive like steel so no rust. It's a great TIG wire for such work.

As for gas welding, it's really hard to do panels because the flame is less focused. More important to get it in there strong first, then make it pretty. I've had to patch tank floor plates too. I have run SB wire in my MIG and stitched them in. Works week with less distortion. Also keep a damp rag nearby to quench the patch panel frequently to prevent oil canning. A little filler, a little grinding, and Bobs your uncle!
'74 550 Build http://forums.sohc4.net/index.php?topic=126401.0
'73 500 Build http://forums.sohc4.net/index.php?topic=132935.0

"Of all tyrannies, a tyranny sincerely exercised for the good of it's victim may be the most oppressive. It may be better to live under robber barons than under omnipotent moral busybodies. The robber baron's cruelty may sometimes sleep, his cupidity may at some point be satiated, but those who torment us for our own good will torment us without end for they do so with the approval of their own conscience." - C.S. Lewis

Offline Jnel

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Re: 1978 750F The start of a big project.
« Reply #136 on: August 24, 2017, 01:19:00 PM »
No leaks, looks straight primed, functional.  What's not to like? Apparently, nothing a grinder and some filler couldn't sort out.
Exactly what t thought. 

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