Author Topic: 1976 cb750f cafe build  (Read 2365 times)

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Offline tekkie

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1976 cb750f cafe build
« on: July 25, 2018, 01:01:38 PM »
A few months ago i finally purchased my first motorcycle, i love fast cars and i have always said if i buy a motorcycle i will be dead the first day. So with that i figured lets start with something small to learn so i purchased a brand new Ninja 300 which i like but i have always liked cafe bikes and somehow i got it into my head to build one. Started doing some research and came to the conclusion that a cb was a good way to go. So i looked on craigslist and facebook and saw one 15 mins from house that was non running / cheap and in decent shape and it was a supersport so i went and picked it up. The kid who had it had a bunch of bikes along with his parents and was honest about all the stuff wrong / missing.

So a 4900 mile 76 CB750F i have that has never been modified that i can tell but the last time it was titled was over 20 years ago and apparently thats the last time it had been driven.

I think i have watched nearly every cb750 video on youtube trying to figure how to get it to start. Compression, spark, gas but no go? after many videos and many hours i took apart the carbs for cleaning but could not get the jets cleaned out from all the crud in there. Ordered some tools, new plugs, pamco, new coils and put all of that in as well as a better cleaning of the carbs and finally i could get it running via starter spray.

Finally i got it running after i realized it was no longer getting enough fuel, turned out the inline fuelfilter that i installed got gummed up and wasnt supplying fuel fast enough. Noticed this when i drained one of the carbs that neraly no gas came out and once i removed that filter it started the first try.  ;D  ;D  ;D. horray


Offline tekkie

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Re: 1976 cb750f cafe build
« Reply #1 on: July 25, 2018, 01:09:04 PM »
so far i have only stripped some weight from it but i have ordered the seat and hoop to start that part

after i plan to cleanup everything and paint it, get the brakes an upgrade and working again and to end up with something similar to this




Offline SOHC4 Cafe Racer Fan

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Re: 1976 cb750f cafe build
« Reply #2 on: July 25, 2018, 03:59:01 PM »
Spoked F models (1975-76) are getting a little less plentiful.  Here's to getting that bike back to running condition.  Nice inspiration bike, too.
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 seanbarney41

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Re: 1976 cb750f cafe build
« Reply #3 on: July 25, 2018, 04:16:43 PM »
Why do you think that you need a tail hoop?
If it works good, it looks good...

Offline tekkie

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Re: 1976 cb750f cafe build
« Reply #4 on: July 25, 2018, 07:50:53 PM »
Spoked F models (1975-76) are getting a little less plentiful.  Here's to getting that bike back to running condition.  Nice inspiration bike, too.
tks

Offline tekkie

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Re: 1976 cb750f cafe build
« Reply #5 on: July 25, 2018, 07:51:31 PM »
Why do you think that you need a tail hoop?

need i dont but i like that look :)

Offline calj737

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Re: 1976 cb750f cafe build
« Reply #6 on: July 26, 2018, 02:59:07 AM »
Why do you think that you need a tail hoop?
need i dont but i like that look :)
The bike pictured has a recessed LED strip in the hoop for tail/brake and turns. Can’t pull that off without closing the rear.

Regarding your gas flow issue, sounds as though the tank needs some dire attention if the inline filter is gummed up.
'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 calj737

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Re: 1976 cb750f cafe build
« Reply #7 on: July 26, 2018, 03:01:46 AM »
By the way, the bike pictured is for sale  ;) Can save you a whole lot of time and trouble building it by just buying it!
'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 tekkie

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Re: 1976 cb750f cafe build
« Reply #8 on: July 26, 2018, 06:03:28 AM »
Why do you think that you need a tail hoop?
need i dont but i like that look :)
The bike pictured has a recessed LED strip in the hoop for tail/brake and turns. Can’t pull that off without closing the rear.

Regarding your gas flow issue, sounds as though the tank needs some dire attention if the inline filter is gummed up.

i have since flushed the tank out, it already has a liner that looks ok but if the issue happens again then i guess i will have to redo it

for the recessed led strip thats exactly what i plan to do, so time to start cutting snd welding next week ;)

Offline tekkie

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Re: 1976 cb750f cafe build
« Reply #9 on: July 26, 2018, 06:04:36 AM »
By the way, the bike pictured is for sale  ;) Can save you a whole lot of time and trouble building it by just buying it!

where would the fun in that be? lol

Offline calj737

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Re: 1976 cb750f cafe build
« Reply #10 on: July 26, 2018, 06:07:56 AM »
That hoop with its recessed strip, is a far more tricky fabrication project than you think. The recess is cut post-bend, the backing support is welded internally to set the recess depth, and the ends of the interior recess are open for routing the wiring. Trust me, its a LOT of work to make that.

If you are considering pie-cut for your hoop, best to do the actual math, use a high quality bandsaw, and make LOTS of pie slices to create a fluid curvature. Nothing looks worse than chunky sections  :o It screams "AMATEUR" and "LAZY" all in one breath.  ;)
'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 tekkie

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Re: 1976 cb750f cafe build
« Reply #11 on: July 26, 2018, 06:23:18 AM »
i purchased one pre bent and if necessary then yeah i will need to cut up some pies possibly to get the correct shape and tig weld them on, and i do have a good metal bandsaw so no worries there

for the led i am going to likely create a 3D printed part that i can put inside the cut out so its nice and clean

Offline calj737

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Re: 1976 cb750f cafe build
« Reply #12 on: July 26, 2018, 06:24:11 AM »
That will work out nicely then.  :)
'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 tekkie

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Re: 1976 cb750f cafe build
« Reply #13 on: July 26, 2018, 06:47:39 AM »
That will work out nicely then.  :)
like you said it will be far more difficult than it sounds lol

i may end up taking the hoop to work and create a 3d copy with a cmm because getting the proper curve for the 3d print will be the hardest part i think

Offline SOHC4 Cafe Racer Fan

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Re: 1976 cb750f cafe build
« Reply #14 on: July 26, 2018, 09:04:13 AM »
That's great to have those work resources available to you.  Looking forward to seeing what you cook 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