Author Topic: 1978 CB750F3 Cafe Racer Project...just starting...  (Read 8690 times)

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Offline SOHC4 Cafe Racer Fan

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Re: 1978 CB750F3 Café Racer Project...just starting...
« Reply #25 on: September 22, 2014, 03:17:48 PM »
The brake calipers I was referring to are:
1985 CB900F
1982 VT1000C

These will mount up using the same fork mounts as your F calipers and give you 2-pistons each (versus the F's single piston calipers).  They look period correct and will provide a substantial upgrade to your stopping power.
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 Davidov

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Re: 1978 CB750F3 Café Racer Project...just starting...
« Reply #26 on: September 22, 2014, 04:34:48 PM »
The brake calipers I was referring to are:
1985 CB900F
1982 VT1000C

These will mount up using the same fork mounts as your F calipers and give you 2-pistons each (versus the F's single piston calipers).  They look period correct and will provide a substantial upgrade to your stopping power.


I've heard pads are readily available for those calipers as well.
-David

Offline quebec_monstro

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Re: 1978 CB750F3 Café Racer Project...just starting...
« Reply #27 on: September 23, 2014, 05:20:35 PM »
Assuming you are keeping your Comstars, and you want to improve the handling, then you will need to stay with the stock front forks.  I would recommend rebuilding them with Race Tech internals (springs and Gold valve emulators).  In addition, you might be able to add a Tarozzi fork brace to improve the rigidity and feel of the front.  Further, If you want to improve the brakes, you can swap the calipers to a twin piston caliper that directly bolts on to your forks.  A couple of Honda models are compatible.  Run a search on the upper left and it will give you the models and date ranges.

I thank you very much for your comments :) In fact i will surely keep the comstars wheels...so i'll keep the original forks...i'll probably also follow your advises as for the forks internals and fork brace :)

As for the pods filter...am I better with the ones sold by APE, dynoman or Cycle X ???

The ones from APE are not the same shape as the other ones...


Offline SOHC4 Cafe Racer Fan

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Re: 1978 CB750F3 Café Racer Project...just starting...
« Reply #28 on: September 23, 2014, 07:19:05 PM »
Assuming you are keeping your Comstars, and you want to improve the handling, then you will need to stay with the stock front forks.  I would recommend rebuilding them with Race Tech internals (springs and Gold valve emulators).  In addition, you might be able to add a Tarozzi fork brace to improve the rigidity and feel of the front.  Further, If you want to improve the brakes, you can swap the calipers to a twin piston caliper that directly bolts on to your forks.  A couple of Honda models are compatible.  Run a search on the upper left and it will give you the models and date ranges.

I thank you very much for your comments :) In fact i will surely keep the comstars wheels...so i'll keep the original forks...i'll probably also follow your advises as for the forks internals and fork brace :)

As for the pods filter...am I better with the ones sold by APE, dynoman or Cycle X ???

The ones from APE are not the same shape as the other ones...

I would recommend buying some quality K&N filters.
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 brandEn

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Re: 1978 CB750F3 Café Racer Project...just starting...
« Reply #29 on: September 23, 2014, 08:02:48 PM »
Check out my TAO thread for lots of detailed pics and info on my F3 rebuild. I hope it helps you out a bit. Let me give you my opinion on the F2-F3 engine before you sink a bunch of money into it. Knowing what I know now and with all the issues I have had personally I would consider putting a rebuilt or low mileage top end from an early K model on your bike. The 77-78 F models head eats valve guides and the parts are harder to find and more expensive. I think a more reliable and cost effective solution is just to replace the top end. Now I am not saying it can't be rebuilt and be reliable I am just putting an option out there that you might want to consider. I love my F3 but its been a real hassle with the engine. Everything from the final drive shaft, to the larger intake spigots, to the valve guides. Its all been just a little bit harder! I hope you don't take my post the wrong way I am not trying to be a bummer just trying to inform you of potential issues you may encounter.


As for engine parts, the best vendors IMO for the F2-F3 is Cycle X and Dynoman. I got all my stuff from Cycle X and they have been great. Ken really knows his stuff. Buzz aka Dynoman can help as well but a little harder to get a hold of as he only communicates through email in my experience.




Offline quebec_monstro

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And the CB750F3 Cafe Racer project continues...
« Reply #30 on: October 11, 2014, 04:49:39 AM »

As for engine parts, the best vendors IMO for the F2-F3 is Cycle X and Dynoman. I got all my stuff from Cycle X and they have been great. Ken really knows his stuff. Buzz aka Dynoman can help as well but a little harder to get a hold of as he only communicates through email in my experience.

First of all I thank you very much for this comment brandEn :) This brings me alternative to my build but sincerely I'll probably keep the F3 head because I like having something a little special  :D

So now here is where I stand right now...the engine is now removed frome the frame. Thanks to some tricks I've discovered on this forum the process went very well...I just had some difficulties but I was able to do that all alone and nothing was damaged during the process...So I'm happy with the results  8)

So next step will be to send the frame to the sandblast and bring down everything into my house's basement before it becomes to cold in my garage to work on my project...Stay tuned for the next steps...

Ho yes and I also began opening the engine :)












Offline Davidov

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Re: 1978 CB750F3 Café Racer Project...just starting...
« Reply #31 on: October 11, 2014, 11:05:31 AM »
Looking good! You really went down to the bare bones.
You really made easy work of that engine removal.

My F3 was originally black, I like the stock color scheme.
-David

Offline SOHC4 Cafe Racer Fan

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Re: 1978 CB750F3 Café Racer Project...just starting...
« Reply #32 on: October 11, 2014, 12:19:10 PM »
It's funny.  When I bought my first CB years ago, I was all for the K look (aluminum and black) engine.  I still like some highlights, but now a simple all satin black motor has a definite appeal, 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 quebec_monstro

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Re: 1978 CB750F3 Café Racer Project...just starting...
« Reply #33 on: November 01, 2014, 12:07:43 PM »
Hi Everyone,

Here are some updates on my project going on....

I removed all parts associated with the Camshaft, cam towers, etch...

The cam lobes seems to have some unacceptable wear along with the Camshaft...I'll post pics when I'll get some times...

So here are some pictures of the last progress :












Offline Davidov

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Re: 1978 CB750F3 Café Racer Project...just starting...
« Reply #34 on: November 01, 2014, 07:22:11 PM »
I can see the wear on the camshaft, the Cyl 3 exhaust side?

You could possibly have a company regrind it for better characteristics. A used stock replacement might be cheaper.
-David

Offline quebec_monstro

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Re: 1978 CB750F3 Café Racer Project...just starting...
« Reply #35 on: November 02, 2014, 04:00:53 AM »
I thank you Davidov for the recommendation :)

i don't konw yet what I'll do with that...

Offline quebec_monstro

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Re: 1978 CB750F3 Café Racer Project...just starting...
« Reply #36 on: November 21, 2014, 09:20:39 AM »
Hi everyone, Here are some news on my progress :

I began cuting the frame so I'll be able to fit my new Ian Halcott Cafe Racer Seat that I recently bought...:)

On top of that the engine is now fully opened and I'm planing on removing the valves this weekend...I'll post more pictures of it soon...

Ho and by the way I would be really interested on seeing how you guys up there made that seat installation on their bikes....PLEASE :)
















Offline SOHC4 Cafe Racer Fan

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Re: 1978 CB750F3 Café Racer Project...just starting...
« Reply #37 on: November 21, 2014, 02:38:22 PM »
I think I saw your seat and oil tank on Ian's mock-up (mule) bike, when I was up there November 7th.  Ian's work is tip top. 
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 quebec_monstro

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Re: 1978 CB750F3 Café Racer Project...just starting...
« Reply #38 on: November 23, 2014, 04:44:22 AM »
Maybe it was mine...I don't know :)

I just removed the valves from the head yesterday...and god I've never tought it would be possible to get valves with that kind of gap within the valve guides  :-\

I red the bad news about F heads and I was aware...but to discover that much plays between the valve stems and guides...I'm just speachless...

 

Offline quebec_monstro

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Re: 1978 CB750F3 Café Racer Project...just starting...
« Reply #39 on: December 04, 2014, 03:42:08 AM »
Ok guys here are some progress:
Cuting all unecessary brackets of the frame is progressing well and Now I've been able to have a first sight of what will be the final result :





I'm  progressing slowly but surely :)

Offline SOHC4 Cafe Racer Fan

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Re: 1978 CB750F3 Café Racer Project...just starting...
« Reply #40 on: December 04, 2014, 08:08:28 AM »
You may also want to weld in mounts for rear sets. Also, if you are planning to hide your electronics under the seat or even just the battery, now is a good time to sort out those mounting points.
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 Prez1967

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Re: 1978 CB750F3 Café Racer Project...just starting...
« Reply #41 on: December 07, 2014, 07:35:55 AM »
Looking good!!!! Some real progress here... Looking forward to following the build!

Offline quebec_monstro

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Re: 1978 CB750F3 Cafe Racer Project...just starting...
« Reply #42 on: January 17, 2015, 05:37:57 AM »
Hi everyone, here are some updates...

Recently I've been working on my frame to cut all unecessary bracket to help save some weights.

So now brackets for the center stand are gone, brackets for holding the airbox also, brackets for the seat latche and original seat fixation on frame and finally the one for locking at angle the top triple clamp (I plan to re locate the ignition switch anyway...)

So here are some pictures of the progress :













Here is the weights savings result  :D:



Recently I've seen pictures of CB 750 with the TC Bros Chopper side stand installed and I'm really considering or replacing the side stand and remove also the frame welded bracket for the original one...

Are there some of you guys who did that modification?? Is that worth it??

Here is the picture from Cognito Moto :



Offline turkey4me

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Re: 1978 CB750F3 Cafe Racer Project...just starting...
« Reply #43 on: January 17, 2015, 10:01:22 AM »
Great work so far.  While you're working on the frame, grind down the lower front right engine mount per Hondaman's book.  This makes it so much easier to install the motor.  Or get a frame mod kit.  Took me 3 minutes to pull the motor and 3 hours fussin' about to install.  Like that seat pan...

Offline Davidov

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Re: 1978 CB750F3 Cafe Racer Project...just starting...
« Reply #44 on: January 18, 2015, 08:07:24 AM »
Great work so far.  While you're working on the frame, grind down the lower front right engine mount per Hondaman's book.  This makes it so much easier to install the motor.  Or get a frame mod kit.  Took me 3 minutes to pull the motor and 3 hours fussin' about to install.  Like that seat pan...

Good advice
-David