Author Topic: CB750 K4 Build - The Cafe Tracer  (Read 118708 times)

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Offline Stev-o

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Re: CB750 K4 Build
« Reply #550 on: March 02, 2017, 06:09:08 PM »
Sorry to hear the ss lines didn't work out. 

Good luck on the start up!

Thanks, Steve.  It's all an experiment so if that's the worst of it I'll take it.  I noticed the oil lines on the Park Racer.  Don't look stock.  Where'd they come from?

Not stock, but they are an upgraded stock line done by forum member Mo.   He zinc coated the fittings and fitted new ss hoses.   He made a limited amount of these for us. 
'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 #551 on: March 02, 2017, 06:21:36 PM »

Not stock, but they are an upgraded stock line done by forum member Mo.   He zinc coated the fittings and fitted new ss hoses.   He made a limited amount of these for us.

Cool.  They look great.
Bud

1973 CB750K3 Chopper
2021 Indian Scout

Offline budman

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Re: CB750 K4 Build
« Reply #552 on: March 04, 2017, 03:10:14 PM »
Ladies and gentlemen, she has a heartbeat.

Bud

1973 CB750K3 Chopper
2021 Indian Scout

Offline budman

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Re: CB750 K4 Build
« Reply #553 on: March 05, 2017, 06:53:04 AM »
I started the bike for the first time yesterday.  The first attempt didn't work because the battery was too weak from testing the different circuits during the wiring phase.  A few hours on the charger and the engine fired right up.  After it warmed up I messed with the timing and ran it for about 20 minutes at different speeds.  Everything appears to be OK.  Got oil pressure.  It's charging.  Kill switch works.  It was a great day.

I'm waiting on the airbox to get back from the powder coater before I attempt to sync the carbs.  Hoping it will be ready this week.  I'm hoping to have the gas tank polished today.  Would love to take a test ride at least up and down the street before spring break.
Bud

1973 CB750K3 Chopper
2021 Indian Scout

Offline Stev-o

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Re: CB750 K4 Build
« Reply #554 on: March 05, 2017, 06:56:45 AM »
Congrats, Bud!   Great feeling that first start up is.

BTW - use a fan blowing on the cylinders when running the motor on the lift. 
'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 #555 on: March 05, 2017, 07:34:54 AM »
Congrats, Bud!   Great feeling that first start up is.

BTW - use a fan blowing on the cylinders when running the motor on the lift.

Thanks, Steve.  Had the fan going the whole time.
Bud

1973 CB750K3 Chopper
2021 Indian Scout

Offline palepainter

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Re: CB750 K4 Build
« Reply #556 on: March 05, 2017, 08:03:57 AM »
Congrats Bud.  I'm sure that had to be a great feeling!!!

Offline budman

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Re: CB750 K4 Build
« Reply #557 on: March 05, 2017, 08:50:08 AM »
Congrats Bud.  I'm sure that had to be a great feeling!!!

Thanks, Mike.  Was a great feeling, especially after the engine tear down.
Bud

1973 CB750K3 Chopper
2021 Indian Scout

Offline markreimer

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Re: CB750 K4 Build
« Reply #558 on: March 05, 2017, 11:46:27 AM »
Video!!!!!!


Sent from my iPhone using Tapatalk

Offline budman

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Re: CB750 K4 Build
« Reply #559 on: March 05, 2017, 12:29:54 PM »
Video!!!!!!

Got one, but can't figure out how to upload it via Tapatalk.
Bud

1973 CB750K3 Chopper
2021 Indian Scout

Offline markreimer

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Re: CB750 K4 Build
« Reply #560 on: March 05, 2017, 12:39:46 PM »
Been having that same issue for the last two weeks or so. It's like the video upload button was removed from the app or something.

Offline budman

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Re: CB750 K4 Build
« Reply #561 on: March 05, 2017, 02:16:16 PM »
Been having that same issue for the last two weeks or so. It's like the video upload button was removed from the app or something.

On 2/28 they claimed to be upgrading the video upload server.
Bud

1973 CB750K3 Chopper
2021 Indian Scout

Offline budman

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Re: CB750 K4 Build
« Reply #562 on: March 06, 2017, 04:50:20 PM »
Got home from work tonight and fired up the CB750 just to make sure Saturday wasn't a dream. 

Had to add some oil now that the engine's been cycling.  Holding good pressure.  Found a small leak.  Thought it was the valve cover but I think it's the tach plug.  Gotta stuff some sealant in there or something.

I also jacked up the back of the bike and went through all the gears a few times.  Shifted smoothly.  Clutch is working great.

It all looks promising.  Sure wish the powder coater would get my airbox done though.

I didn't get to finish up the tank yesterday.  Was raining cats, dogs and a few other animals  yesterday and I couldn't take the noise of the rain on the metal roof.  Gotta find some time this week to get that done.
Bud

1973 CB750K3 Chopper
2021 Indian Scout

Offline SOHC4 Cafe Racer Fan

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Re: CB750 K4 Build
« Reply #563 on: March 06, 2017, 05:14:53 PM »
If you have a tach plug, it might be missing an o-ring.  Don't put RVT on it.
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 #564 on: March 06, 2017, 05:28:54 PM »
If you have a tach plug, it might be missing an o-ring.  Don't put RVT on it.

Has an o-ring.  Must be a bad fit.  Probably use some Three-bond.
Bud

1973 CB750K3 Chopper
2021 Indian Scout

Offline budman

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Re: CB750 K4 Build
« Reply #565 on: March 10, 2017, 12:30:23 PM »
Fixed the leak at the tach plug with some Three-bond.  The O-ring is way too thin in my opinion.  Needs to be fatter with more surface area contact.

But now I've detected a leak at the neutral safety switch.  That's the one O-ring I did not change.  For whatever reason I did not pull the switch out.  I can't recall my reasoning.  Looks like I've got to deal with it now.
Bud

1973 CB750K3 Chopper
2021 Indian Scout

Offline MauiK3

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Re: CB750 K4 Build
« Reply #566 on: March 11, 2017, 08:29:18 AM »
Looks wonderful, what a build. And thank you for your help with my slow moving project. As I move through I am discovering many small problems, none of which are very big. I replaced the ignition and air box which really made a difference. When I "analyze " it enough the motor will come out for freshening up.
By the way, your valve cover is beautiful. Is it all just hand polished? Did you coat it with anything? Also, did you fiat the engine block? Sorry if it's in the posts somewhere, I admit I have not read the entire string.
Steve
1973 CB 750 K3
10/72 build Z1 Kawasaki

Offline budman

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Re: CB750 K4 Build
« Reply #567 on: March 11, 2017, 08:54:40 AM »
Looks wonderful, what a build. And thank you for your help with my slow moving project. As I move through I am discovering many small problems, none of which are very big. I replaced the ignition and air box which really made a difference. When I "analyze " it enough the motor will come out for freshening up.
By the way, your valve cover is beautiful. Is it all just hand polished? Did you coat it with anything? Also, did you fiat the engine block? Sorry if it's in the posts somewhere, I admit I have not read the entire string.
Steve


Thanks, Steve.

I had the valve cover and all the engine covers chrome plated.  I didn't want to spend the time polishing or maintaining the factory aluminum.  I do enough of that on my other bike.

The silver head and the gun metal cases are painted with a metallic single stage acrylic urethane.  They were supposed to come out glossy, but looks more like a semi gloss.  The cylinders are painted with the same gloss black urethane I used on the frame and most of the rest of the black parts you see on the bike.

Did you find your points screws?
Bud

1973 CB750K3 Chopper
2021 Indian Scout

Offline budman

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CB750 K4 Build
« Reply #568 on: March 11, 2017, 05:55:41 PM »
Today I drained the oil out of the oil pan and I pulled the neutral safety switch.  I was lucky to find a new o-ring at the local Honda dealer.  Got it all back in place, but it's still leaking a little bit, not as bad though.  Hope the oil will make the o-ring swell up.  I guess I could coat the o-ring with a little three-bond.  What a crappy design.

I also checked and re-adjusted the valve tappets as needed now that the engine has been run a little bit.  Nothing major out of whack.  Seems to run a little quieter and smoother though....or I might just be imagining it.

I got about half the gas tank polished.  It'll have to wait to be finished.  I'm going to be on vacation next week and in two weeks I'll be riding around the Texas Hill country, but not on this CB750.  I'll still have fun, but I really want to finish this bike and ride it.

Oh yeah...I also got a good look at a new CB1000 at the Honda dealer.  Really nice looking bike.  Would love to take one for a ride.
« Last Edit: March 11, 2017, 06:14:21 PM by budman »
Bud

1973 CB750K3 Chopper
2021 Indian Scout

Offline MauiK3

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Re: CB750 K4 Build
« Reply #569 on: March 11, 2017, 06:33:11 PM »
Yes, I found the ignition screws at Davis Silver Spares. Once I knew the Honda part number it was easy, they're not very expensive.
Steve
1973 CB 750 K3
10/72 build Z1 Kawasaki

Offline budman

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CB750 K4 Build
« Reply #570 on: March 20, 2017, 05:10:23 PM »
I got the airbox parts back from the powder coater, but I can't remember what I did with the set screws.  Gotta get some more.

The safety switch is still leaking so I bought a brand new one and another new o-ring.  Hope it stops the leak.

I'll be heading out of town for a bike ride this weekend.  It'll all have to wait another week before I have everything ready for the first test ride.

Bud

1973 CB750K3 Chopper
2021 Indian Scout

Offline SOHC4 Cafe Racer Fan

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Re: CB750 K4 Build
« Reply #571 on: March 20, 2017, 05:46:54 PM »
Pretty! Hope it performs as good as it looks!!
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 #572 on: March 31, 2017, 06:40:40 PM »
I've had some billet clutch lifter plates made.  I'm giving away five of them.  Details in the Free Stuff forum in the Classifieds.

Bud

1973 CB750K3 Chopper
2021 Indian Scout

Offline Stev-o

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Re: CB750 K4 Build
« Reply #573 on: April 01, 2017, 08:11:51 AM »
Looks like a quality piece, 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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CB750 K4 Build
« Reply #574 on: April 01, 2017, 05:28:21 PM »
I thought today was going to be the day I made my first test ride.  Didn't happen.  I had some trouble syncing the carbs, but I eventually figured it out.  Helps if you read the manual.  The bike sounds good and has quick throttle response.

I got the front brake bled.  All good there.  I just need to finish polishing the gas and mount it on the bike, put some gas in it and I should be ready to go.

There's three clutch lifter plates left...
Bud

1973 CB750K3 Chopper
2021 Indian Scout