Author Topic: CB750 K4 Build - The Cafe Tracer  (Read 118665 times)

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Offline Stev-o

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Re: CB750 K4 Build
« Reply #50 on: November 10, 2014, 04:35:29 PM »
I like the tank, Bud.  Wish I had a GT750!
'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

Offline budman

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Re: CB750 K4 Build
« Reply #51 on: November 10, 2014, 05:33:18 PM »
Thanks, Steve.  I think it'll look good when it's all done.
Bud

1973 CB750K3 Chopper
2021 Indian Scout

Offline budman

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CB750 K4 Build
« Reply #52 on: November 22, 2014, 04:19:09 PM »
Worked on the tank today.  I laid out how I wanted the knee insert to look on one side of the tank, then made a pattern that I  reversed and traced on to the opposite side.  I cut the sections out of the tank and bent some sheet metal around a piece of pipe to fit the contour that makes the knee inserts (who needs a slip roll).  A little hammering and trimming and it's looking pretty good.  I got one side almost ready to weld.  I'm hoping to get the other side close to being finished tomorrow.
« Last Edit: November 22, 2014, 05:23:33 PM by budman »
Bud

1973 CB750K3 Chopper
2021 Indian Scout

Offline budman

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Re: CB750 K4 Build
« Reply #53 on: November 22, 2014, 04:22:44 PM »
More tank pics...

I'm going to cut off the old filler and weld in a Harley style filler bung.  I don't really like the flip caps.  I'm also going to use a 22mm Harley style bung for the fuel petcock, installed on the left side.
Bud

1973 CB750K3 Chopper
2021 Indian Scout

Offline Tews19

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Re: CB750 K4 Build
« Reply #54 on: November 22, 2014, 05:17:25 PM »
WOW, the tank looks great!
1969 Honda CB750... Basket case
1970 Honda CB750 survivor.

Offline SOHC4 Cafe Racer Fan

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Re: CB750 K4 Build
« Reply #55 on: November 22, 2014, 05:23:16 PM »
Fantastic job on the tank!  8)
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 budman

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Re: CB750 K4 Build
« Reply #56 on: November 22, 2014, 05:27:23 PM »
Thanks.
Bud

1973 CB750K3 Chopper
2021 Indian Scout

Offline Stev-o

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Re: CB750 K4 Build
« Reply #57 on: November 22, 2014, 06:41:57 PM »
Impressive metal skills, Bud. 
'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

Offline budman

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Re: CB750 K4 Build
« Reply #58 on: November 22, 2014, 07:09:18 PM »
Thanks, Steve.  I was an auto body repair tech many moons ago.
Bud

1973 CB750K3 Chopper
2021 Indian Scout

Offline greenjeans

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Re: CB750 K4 Build
« Reply #59 on: November 23, 2014, 06:24:08 PM »
Never thought to try a GT tank on my Honda's - looks good.   Really like the line you chose for the knee cutouts - follows the front edge and really looks great from the top.
Yep, I'm the kid that figured out how to put things back together...eventually.

Offline budman

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CB750 K4 Build
« Reply #60 on: November 23, 2014, 06:36:39 PM »
Never thought to try a GT tank on my Honda's - looks good.   Really like the line you chose for the knee cutouts - follows the front edge and really looks great from the top.

Thanks.  I played around with some sketches before I dug in and decided to make the lines mimic the front of the tank.  It doesn't look like random or oddball...to me anyway.  The tank's not a direct fit.  It's taking a little head scratching, but I'll make it work.

I got the other side pretty much fitted and ready to go today.  I also made a filler panel for the front/top of the tank.  The opening at the front is too large.  There's a factory cover that supposed to go there, which I don't have and didn't want to use anyway.  I'll weld in the filler plate and smooth it all out.

I also got the old fuel filler cut off.  The new filler bung fits great.  Should work out just fine.
« Last Edit: November 23, 2014, 07:44:07 PM by budman »
Bud

1973 CB750K3 Chopper
2021 Indian Scout

Offline budman

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Re: CB750 K4 Build
« Reply #61 on: November 24, 2014, 04:24:14 PM »
My Cycle X Alpha front end rebuild kit came in today.  They were able to put together a custom kit for me with -2" tubes.  Looks like quality parts.  I really like the look of the triple trees.
Bud

1973 CB750K3 Chopper
2021 Indian Scout

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Re: CB750 K4 Build
« Reply #62 on: November 24, 2014, 04:35:16 PM »
My Cycle X Alpha front end rebuild kit came in today.  They were able to put together a custom kit for me with -2" tubes.  Looks like quality parts.  I really like the look of the triple trees.

$450 for almost an entire rebuilt front with billet triples.  Not a bad deal!
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 budman

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Re: CB750 K4 Build
« Reply #63 on: November 24, 2014, 05:59:45 PM »
Yep. Not a bad deal at all.
Bud

1973 CB750K3 Chopper
2021 Indian Scout

Offline budman

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Re: CB750 K4 Build
« Reply #64 on: November 26, 2014, 11:46:05 AM »
I got the tank and the new panels blasted.  I'll be welding on Saturday!
Bud

1973 CB750K3 Chopper
2021 Indian Scout

Offline budman

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Re: CB750 K4 Build
« Reply #65 on: November 29, 2014, 04:53:58 PM »
...after about 6 hours of fitting, welding and grinding today.
Bud

1973 CB750K3 Chopper
2021 Indian Scout

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Re: CB750 K4 Build
« Reply #66 on: November 30, 2014, 01:37:13 AM »
No small feat. Keep it up!
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 Stev-o

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Re: CB750 K4 Build
« Reply #67 on: November 30, 2014, 10:02:10 AM »
Looks good Bud. You plan to coat the inside?
'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

Offline budman

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Re: CB750 K4 Build
« Reply #68 on: November 30, 2014, 12:06:23 PM »
Yeah, with all that welding I'm going to have to.  I'm going to pressure test it but it'll need to be sealed.  I've done several tanks and had good luck with Kreem tank seal.
Bud

1973 CB750K3 Chopper
2021 Indian Scout

Offline budman

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Re: CB750 K4 Build
« Reply #69 on: December 01, 2014, 01:47:04 PM »
The rear rubber mount for the stock tank that came with the bike was ripped so the tank came right off.  I can see how it's supposed to all fit together, but don't quite understand how to remove or install the tank without the rear rubber mount being torn.  I can't make out how you're supposed to slide the tank on or off the frame.  How's that work?
Bud

1973 CB750K3 Chopper
2021 Indian Scout

Offline budman

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Re: CB750 K4 Build
« Reply #70 on: December 20, 2014, 06:53:50 PM »
I finished welding the tank last week.  I had to add some filler panels to the front of the tank because the tunnel opening was too wide.  I also completely eliminated the flanges (or whatever they're called) that are so prevalent on Japanese motorcycle tanks.  I welded the tank up so it's smooth all the way around.  I also made a new rear tank mount.  I cut the stock bracket off the frame and welded in a bung.  Tank fits nice and solid.

I sealed the tank with Red-Kote.  I've never used it before so I thought I'd try it.  I used a slightly modified Dime City tank sealing method.  I used a 50/50 CLR and water mix to clean the inside of the tank and then used water and a rust inhibiter that we sell at work called Hold Tight 102 to flush it out.  Then used denatured alcohol, compressed air and a heat gun to dry it out.  The Red-Kote application was painless.  I opted for two applications of Red-Kote, because of all the welding I did.

I finished up the body work today.  The tank will get primed tomorrow.  It'll be nice to see it one color, at least.
Bud

1973 CB750K3 Chopper
2021 Indian Scout

Offline Stev-o

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Re: CB750 K4 Build
« Reply #71 on: December 20, 2014, 07:00:55 PM »
Nice job, Bud.   You pick a color yet?
'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: CB750 K4 Build
« Reply #72 on: December 20, 2014, 07:28:24 PM »
I finished welding the tank last week.  I had to add some filler panels to the front of the tank because the tunnel opening was too wide.  I also completely eliminated the flanges (or whatever they're called) that are so prevalent on Japanese motorcycle tanks.  I welded the tank up so it's smooth all the way around.  I also made a new rear tank mount.  I cut the stock bracket off the frame and welded in a bung.  Tank fits nice and solid.

I sealed the tank with Red-Kote.  I've never used it before so I thought I'd try it.  I used a slightly modified Dime City tank sealing method.  I used a 50/50 CLR and water mix to clean the inside of the tank and then used water and a rust inhibiter that we sell at work called Hold Tight 102 to flush it out.  Then used denatured alcohol, compressed air and a heat gun to dry it out.  The Red-Kote application was painless.  I opted for two applications of Red-Kote, because of all the welding I did.

I finished up the body work today.  The tank will get primed tomorrow.  It'll be nice to see it one color, at least.

The tank looks great.  You may want to rethink the red-kote.  That stuff starts coming loose with ethanol-based fuel.  Caswell's epoxy based coating seems to be one of the few things that holds up.
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 budman

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Re: CB750 K4 Build
« Reply #73 on: December 20, 2014, 07:29:27 PM »

Nice job, Bud.   You pick a color yet?

Thanks.  I haven't picked out a specific color(s) yet, but it will be some shade of root beer brown with tan racing stripes and probably some orange or red pinstripes somewhere.
Bud

1973 CB750K3 Chopper
2021 Indian Scout

Offline budman

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Re: CB750 K4 Build
« Reply #74 on: December 20, 2014, 07:50:57 PM »

The tank looks great.  You may want to rethink the red-kote.  That stuff starts coming loose with ethanol-based fuel.  Caswell's epoxy based coating seems to be one of the few things that holds up.

It's too late to re-think.  It's done.  I read a lot of positive reviews about Red-Kote.  The Red-Kote folks say it performs as it's supposed using E10-E50 and "generally" performs well with E85. They recommend not using any fuel with a higher ethanol content than E85.  I seriously doubt I'll ever put anything in the tank other than E10.

My only experience with tank sealants is with Kreem. I've used it on three tanks and have not had a failure.  Other than the color Red-Kote seems like a very similar product.  It smells like Kreem, but seems to be more flexible.
Bud

1973 CB750K3 Chopper
2021 Indian Scout