Author Topic: 1973 CB750K3 - One Owner Barn Find - 5,310 miles - Final with Pics  (Read 43641 times)

0 Members and 1 Guest are viewing this topic.

Offline ekpent

  • Really Old Timer ...
  • *******
  • Posts: 13,512
  • To many bikes-but lookin' for more
Re: 1973 CB750K3 - One Owner Barn Find - 5,310 miles
« Reply #50 on: October 25, 2011, 06:12:55 AM »
Hey Johnie those carbs sure do look a little sticky. Were the slides and needles seized with all that goo.I have found the heat gun useful to soften that stuff up and for the jets etc a nice soak in lacquer thinner really cuts and breaks that stuff down before a final cleaning in the dunk. Keep on keepin' on,were with Ya--------    Eric

Offline Johnie

  • Really Old Timer ...
  • *******
  • Posts: 8,613
Re: 1973 CB750K3 - One Owner Barn Find - 5,310 miles
« Reply #51 on: October 25, 2011, 10:28:34 AM »
Eric...yah, those carbs are a bit sticky, right? :) I could tell when I was checking it out those slides and needles were a bit sticky too. I was able to throttle it pretty easy, but could feel the sticking needles. The needles are varnished like the jets, but the slides themselves are not bad. I will get some pics up soon of how the bowls turned out.
1970 CB750K0 - Candy Ruby Red
1973 CB750K3 - Candy Bacchus Olive or Sunflake Orange
1970 Chevy Chevelle SS396 - Cortez Silver
1976 GL1000 Sulphur Yellow

Oshkosh, WI  USA

Offline Johnie

  • Really Old Timer ...
  • *******
  • Posts: 8,613
Re: 1973 CB750K3 - One Owner Barn Find - 5,310 miles
« Reply #52 on: October 25, 2011, 03:05:15 PM »
I am encouraged...take a look at how the bowls cleaned up. The jets are coming along too. The most delicate task will be to free up the float pins without breaking the mounts. Only 1 of the 4 float pins are free. I think I will soak them in place and hope my Gunk carb cleaner will not damage the plastic floats.
1970 CB750K0 - Candy Ruby Red
1973 CB750K3 - Candy Bacchus Olive or Sunflake Orange
1970 Chevy Chevelle SS396 - Cortez Silver
1976 GL1000 Sulphur Yellow

Oshkosh, WI  USA

Offline Johnie

  • Really Old Timer ...
  • *******
  • Posts: 8,613
Re: 1973 CB750K3 - One Owner Barn Find - 5,310 miles
« Reply #53 on: October 26, 2011, 07:08:28 PM »
As of tonight 3 of the 4 float pins have been removed...very carefully I may add. The pins were not stuck so bad on the aluminum pin holders, but were stuck pretty bad to the float bracket. Using some Liquid Wrench to free them up and do very light tapping with my small plastic hammer worked. Big secret to not breaking those fragile float pin holders is to take your time and not rush it. I also made a tool to "push" the pins through slowly rather than use a hammer. The 110 mains and 40 slows cleaned up good. Progress continues...
1970 CB750K0 - Candy Ruby Red
1973 CB750K3 - Candy Bacchus Olive or Sunflake Orange
1970 Chevy Chevelle SS396 - Cortez Silver
1976 GL1000 Sulphur Yellow

Oshkosh, WI  USA

Offline wardenerd

  • Expert
  • ****
  • Posts: 816
  • '77 550F '81 650C
Re: 1973 CB750K3 - One Owner Barn Find - 5,310 miles
« Reply #54 on: October 27, 2011, 05:00:32 AM »
In college I picked up a 1961 t-bird so I got into the T-Bird lore.  Ford Motor Company swears this is true.  A family in California put a used T-bird barn car up for sale and a collector went to see it.  It was a black first year T-Bird with only a few hundred miles. It was covered by hay bales and a tarp and was almost perfectly preserved. .   It belonged to the grandson of the family and he died if I remember correctly from a sudden illness.  Anyway the collector bought the car and when he looked at the paperwork he discovered that the serial number ended in 1.  It was actually the first production T-Bird made by Ford.  The car is on display at a Fordcentric museum if my failing memory is at all clear.  The year of the T-Bird reference book produced by FOMOCO was in the early 70's..

Offline Johnie

  • Really Old Timer ...
  • *******
  • Posts: 8,613
Re: 1973 CB750K3 - One Owner Barn Find - 5,310 miles
« Reply #55 on: October 27, 2011, 06:11:23 AM »
Good story. Can you imagine finding a #1 CB750. I wonder what the lowest build number is among our SOHC group by bike year.
1970 CB750K0 - Candy Ruby Red
1973 CB750K3 - Candy Bacchus Olive or Sunflake Orange
1970 Chevy Chevelle SS396 - Cortez Silver
1976 GL1000 Sulphur Yellow

Oshkosh, WI  USA

Offline Johnie

  • Really Old Timer ...
  • *******
  • Posts: 8,613
Re: 1973 CB750K3 - One Owner Barn Find - 5,310 miles
« Reply #56 on: October 27, 2011, 08:42:19 AM »
Success...got the last float off today. No broken float pin holders. That #4 was a real bugger and did not want to let loose. You just have to walk away a few times and not get to anxious to force it. I mainly used the push pin method rather than a hammer. If I did tap with the hammer is was a light plastic hammer and light tapping to break it free. I so wanted to not break a float pin holder as I really wanted to keep all the OEM parts on this bike. Movin' on....
1970 CB750K0 - Candy Ruby Red
1973 CB750K3 - Candy Bacchus Olive or Sunflake Orange
1970 Chevy Chevelle SS396 - Cortez Silver
1976 GL1000 Sulphur Yellow

Oshkosh, WI  USA

Offline lucky

  • Really Old Timer ...
  • *******
  • Posts: 6,717
Re: 1973 CB750K3 - One Owner Barn Find - 5,310 miles
« Reply #57 on: October 27, 2011, 11:48:33 AM »
Johnie and Scrambler, never really thought about it much, but comparing vin#'s and eng#'s on other members bikes is really a good idea especially with your K3's having the same 10/72 build date. Just a little bit of history think about it you two, in October 39 years ago in Japan the K3's your now have in your garages here in the good USA came of the assembly line in Japan only a couple hundred bikes apart. And now both of these 750's are in Wisconsin and the owners are talking to each other over the internet on this forum about these two bikes all these years later. What are the odds of that happening. Things that make you go hmmm ;D

dhall

Great research.
I bet the internet may cause other changes that will be astounding also.
Think about kids now that will grow up and can have a video of any part of their
life.  What will the repercussions of that be?

Offline ekpent

  • Really Old Timer ...
  • *******
  • Posts: 13,512
  • To many bikes-but lookin' for more
Re: 1973 CB750K3 - One Owner Barn Find - 5,310 miles
« Reply #58 on: October 28, 2011, 05:50:35 AM »
I have pictures of when I was a kid,not that much different  ???  ??? internet just makes kids lazy---

Offline Johnie

  • Really Old Timer ...
  • *******
  • Posts: 8,613
Re: 1973 CB750K3 - One Owner Barn Find - 5,310 miles
« Reply #59 on: October 29, 2011, 07:44:49 AM »
Last night I finished up on the carbs. Just need to set the floats and put the bowls back on. Compare the pics before and after...scarey.  :D
1970 CB750K0 - Candy Ruby Red
1973 CB750K3 - Candy Bacchus Olive or Sunflake Orange
1970 Chevy Chevelle SS396 - Cortez Silver
1976 GL1000 Sulphur Yellow

Oshkosh, WI  USA

Offline dhall57

  • Old Timer
  • ******
  • Posts: 3,676
  • The 70's! SOHC4 Honda's & Marcia Brady of course.
Re: 1973 CB750K3 - One Owner Barn Find - 5,310 miles
« Reply #60 on: October 29, 2011, 09:55:48 AM »
A big improvement. Looking good Johnie ;D
1970 CB750KO
1971 CB500KO-project bike
1973 CB350G- project bike
1974 CB750K4-project bike
1974 CB750K4
1976 CB750K6
1977 GL1000
1997 Harley Wideglide

Offline smpls70

  • Hot Shot
  • ***
  • Posts: 313
Re: 1973 CB750K3 - One Owner Barn Find - 5,310 miles
« Reply #61 on: October 29, 2011, 11:15:45 AM »
Nice lookin set of carbs , where ya have the needle clip position at, just out of couriousity  ( are they 657A ?)
ROTHNOTHAGAR !

Offline Johnie

  • Really Old Timer ...
  • *******
  • Posts: 8,613
Re: 1973 CB750K3 - One Owner Barn Find - 5,310 miles
« Reply #62 on: October 29, 2011, 12:50:31 PM »
With so few miles on the bike I figured it would be all factory stock settings and it was. 657A carbs, 110 mains, 40 slows, needle in position 4 setting.
1970 CB750K0 - Candy Ruby Red
1973 CB750K3 - Candy Bacchus Olive or Sunflake Orange
1970 Chevy Chevelle SS396 - Cortez Silver
1976 GL1000 Sulphur Yellow

Oshkosh, WI  USA

Offline wedoo2

  • Hot Shot
  • ***
  • Posts: 441
Re: 1973 CB750K3 - One Owner Barn Find - 5,310 miles
« Reply #63 on: October 30, 2011, 06:27:11 AM »
My first post as I have been reading.  I am starting a project as well on a 550 and my carbs are in similar shape.   Mind telling me what you soaked everything in and if any of the parts in the pics are new?  It came out looking great.
Some days the sun is too loud.

Offline Johnie

  • Really Old Timer ...
  • *******
  • Posts: 8,613
Re: 1973 CB750K3 - One Owner Barn Find - 5,310 miles
« Reply #64 on: October 30, 2011, 07:27:51 AM »
Welcome weedo...I did not notice that was your first post. You found the right spot for your SOHC for sure. I always had good luck with the Gunk carb cleaner in the paint can with the basket included. Available at my locals Fleet Farm. Good luck with your project.
1970 CB750K0 - Candy Ruby Red
1973 CB750K3 - Candy Bacchus Olive or Sunflake Orange
1970 Chevy Chevelle SS396 - Cortez Silver
1976 GL1000 Sulphur Yellow

Oshkosh, WI  USA

Offline Johnie

  • Really Old Timer ...
  • *******
  • Posts: 8,613
Re: 1973 CB750K3 - One Owner Barn Find - 5,310 miles
« Reply #65 on: October 30, 2011, 11:46:41 AM »
Got the carbs back on the bike today. No issues. Waiting on a new petcock and then hope to fire it up before the snow flies.
1970 CB750K0 - Candy Ruby Red
1973 CB750K3 - Candy Bacchus Olive or Sunflake Orange
1970 Chevy Chevelle SS396 - Cortez Silver
1976 GL1000 Sulphur Yellow

Oshkosh, WI  USA

Offline Johnie

  • Really Old Timer ...
  • *******
  • Posts: 8,613
Re: 1973 CB750K3 - One Owner Barn Find - 5,310 miles
« Reply #66 on: October 30, 2011, 12:18:57 PM »
I was taking a look at the chain and came upon cracks in the links. I was planning to replace it anyway, but I guess this just reinforces the reason to check over a chain once and a while. I have never run across this before. I see the DID stamp on it and would imagine it is the original.
« Last Edit: October 30, 2011, 01:02:42 PM by Johnie »
1970 CB750K0 - Candy Ruby Red
1973 CB750K3 - Candy Bacchus Olive or Sunflake Orange
1970 Chevy Chevelle SS396 - Cortez Silver
1976 GL1000 Sulphur Yellow

Oshkosh, WI  USA

Offline wedoo2

  • Hot Shot
  • ***
  • Posts: 441
Re: 1973 CB750K3 - One Owner Barn Find - 5,310 miles
« Reply #67 on: October 30, 2011, 02:56:19 PM »
The carbs  look good, no, they look great.  Have you, or anyone else, have any experience soaking them in pine sol?  One of the guys in the 750C forum swears by this.
Some days the sun is too loud.

Offline Johnie

  • Really Old Timer ...
  • *******
  • Posts: 8,613
Re: 1973 CB750K3 - One Owner Barn Find - 5,310 miles
« Reply #68 on: October 30, 2011, 05:01:25 PM »
Never tried the Pin-Sol. I guess most of us find something that seems to work good and stick with it.
1970 CB750K0 - Candy Ruby Red
1973 CB750K3 - Candy Bacchus Olive or Sunflake Orange
1970 Chevy Chevelle SS396 - Cortez Silver
1976 GL1000 Sulphur Yellow

Oshkosh, WI  USA

Offline Johnie

  • Really Old Timer ...
  • *******
  • Posts: 8,613
Re: 1973 CB750K3 - One Owner Barn Find - 5,310 miles
« Reply #69 on: October 31, 2011, 03:12:26 PM »
Today got the new spark plugs in and put a fresh battery in to work on my no spark issue on 2 & 3. Got that issue taken care of and now waiting for some parts from my dealer. Installing new air box rubbers, OEM air filter, and petcock. Then clean the tank and I should be ready to wake this beast up from a 24 year rest.
1970 CB750K0 - Candy Ruby Red
1973 CB750K3 - Candy Bacchus Olive or Sunflake Orange
1970 Chevy Chevelle SS396 - Cortez Silver
1976 GL1000 Sulphur Yellow

Oshkosh, WI  USA

Offline ekpent

  • Really Old Timer ...
  • *******
  • Posts: 13,512
  • To many bikes-but lookin' for more
Re: 1973 CB750K3 - One Owner Barn Find - 5,310 miles
« Reply #70 on: October 31, 2011, 08:45:01 PM »
What kind of issue did you have with the 2/3 Johnie,were the points dirty?. Surprised you don't have a slave tank set up to run those bikes a little when your working on them,I  always get nervous taking nice tanks on and off. How is the clutch doing in that one,is it free ? Everthing is looking very nice.

Offline 754

  • Really Old Timer ...
  • *******
  • Posts: 29,058
Re: 1973 CB750K3 - One Owner Barn Find - 5,310 miles
« Reply #71 on: November 01, 2011, 10:05:07 AM »
 Check the battery vent tube, may cause chain cracking..

 if chain ir original, I believe it should be endless..
Maker of the WELDLESS 750 Frame Kit
dodogas99@gmail.com
Kelowna B.C.       Canada

My next bike will be a ..ANFOB.....

It's All part of the ADVENTURE...

73 836cc.. Green, had it for 3 decades!!
Lost quite a few CB 750's along the way

Offline Johnie

  • Really Old Timer ...
  • *******
  • Posts: 8,613
Re: 1973 CB750K3 - One Owner Barn Find - 5,310 miles
« Reply #72 on: November 01, 2011, 11:49:59 AM »
754 you are correct it was an endless chain. Eric, I cleaned the points and put in a new battery with new plugs. I have a feeling that when I was doing the compression and circulating the oil via the starter I ran the battery down to low to give much spark. Put the new battery in and great spark now. Clutch, I have not tried anything with that yet. I never had a problem with it on any of the other 750's so never gave it a thought if it could be stuck.
« Last Edit: November 01, 2011, 11:59:52 AM by Johnie »
1970 CB750K0 - Candy Ruby Red
1973 CB750K3 - Candy Bacchus Olive or Sunflake Orange
1970 Chevy Chevelle SS396 - Cortez Silver
1976 GL1000 Sulphur Yellow

Oshkosh, WI  USA

Offline Tews19

  • I am no
  • Really Old Timer ...
  • *******
  • Posts: 6,465
Re: 1973 CB750K3 - One Owner Barn Find - 5,310 miles
« Reply #73 on: November 01, 2011, 05:01:15 PM »
Does the 750 allow you to remove the caps and trim the spark plug wires like a 550 stock system does? I did this today on mine and it worked great. OH PLEASE make a video of you trying to start her on the first try??!!??!!
1969 Honda CB750... Basket case
1970 Honda CB750 survivor.

Offline zzpete

  • You better get an
  • Expert
  • ****
  • Posts: 831
  • 1969 CB750, 1971 CB750
Re: 1973 CB750K3 - One Owner Barn Find - 5,310 miles
« Reply #74 on: November 01, 2011, 05:02:07 PM »
Does the 750 allow you to remove the caps and trim the spark plug wires like a 550 stock system does? I did this today on mine and it worked great.
Yes!!
"One of the things that make motorcycling so great because it never fails to give you a feeling of freedom and adventure." - Steve McQueen