« previous next »
Pages: 1 2 3 [4]   Go Down

Author Topic: CB750 K0-1  (Read 15764 times)

0 Members and 1 Guest are viewing this topic.

Offline HondaMan

  • Someone took this pic of me before I became a
  • Really Old Timer ...
  • *******
  • Posts: 14,033
  • ...not my choice, I was nicknamed...
    • Getting 'em Back on the Road
Re: CB750 K0-1
« Reply #75 on: January 17, 2025, 07:42:52 PM »
Quote from: Don R on January 15, 2025, 02:51:17 PM
The pistons I wanted to use had broken middle rings and there were segments riding in the grooves. I'm assuming since the cylinders appear good and the segments are pretty smooth whoever put these pistons onto the sandcast bottom end broke them and it ran like that.

Was it the middle iron ring?
Logged
See SOHC4shop@gmail.com for info about the gadgets I make for these bikes.

The demons are repulsed when a man does good. Use that.
Blood is thicker than water, but motor oil is thicker yet...so, don't mess with my SOHC4, or I might have to hurt you.
Hondaman's creed: "Bikers are family. Treat them accordingly."

Link to Hondaman Ignition: http://forums.sohc4.net/index.php?topic=67543.0

Link to My CB750 Book: https://www.lulu.com/search?adult_audience_rating=00&page=1&pageSize=10&q=my+cb750+book

Link to website: www.SOHC4shop.com

Offline Don R

  • My Sandcast is a
  • Really Old Timer ...
  • *******
  • Posts: 20,197
  • Saver of unloved motorcycles.
Re: CB750 K0-1
« Reply #76 on: January 19, 2025, 05:21:27 PM »
Quote from: HondaMan on January 17, 2025, 07:42:52 PM
Quote from: Don R on January 15, 2025, 02:51:17 PM
The pistons I wanted to use had broken middle rings and there were segments riding in the grooves. I'm assuming since the cylinders appear good and the segments are pretty smooth whoever put these pistons onto the sandcast bottom end broke them and it ran like that.

Was it the middle iron ring?
Yes they both were, I honed the cylinder, and it cleaned up fine. I got a set of rings on the way. I'm getting excited to see it with the motor back in and the set of long awaited Italian 4-4 pipes on it.
  I'm trying to never say the B word. 

 Who needs a 1971 K0?
« Last Edit: January 19, 2025, 05:25:55 PM by Don R »
Logged
No matter how many times you paint over a shadow, it's still there.
 CEO at the no kill motorcycle shop.
 You don't need a weatherman to know which way the wind blows.

Offline BenelliSEI

  • Really Old Timer ...
  • *******
  • Posts: 10,249
  • 1969 cb750
Re: CB750 K0-1
« Reply #77 on: January 20, 2025, 07:13:31 AM »
Parallel lives?
Logged

Offline Don R

  • My Sandcast is a
  • Really Old Timer ...
  • *******
  • Posts: 20,197
  • Saver of unloved motorcycles.
Re: CB750 K0-1
« Reply #78 on: January 20, 2025, 11:06:57 AM »
  We do have a lot of common interests and find similar projects interesting.

  My former fab shop partner/welder is coming by in the next couple weeks after moving 4 hours away. He's buying out my half of the Hossfeld bender and may weld the stainless-steel exhaust on my firebird. He wants to build some race cars again and needs to raise a roll cage on his stepsons Jr Dragster.
  The bottom line is, I need to leave these Hondas alone and get busy re-fitting my exhaust, it rubs the rear of the driveshaft when the axle is hanging from the coil-overs.
Logged
No matter how many times you paint over a shadow, it's still there.
 CEO at the no kill motorcycle shop.
 You don't need a weatherman to know which way the wind blows.

Offline Don R

  • My Sandcast is a
  • Really Old Timer ...
  • *******
  • Posts: 20,197
  • Saver of unloved motorcycles.
Re: CB750 K0-1
« Reply #79 on: January 20, 2025, 11:43:07 PM »
 I did spend some time on the car exhaust but had bike stuff out and want it put away so I worked on the cylinder and head. I did dig out the original head and began to clean it up. I flushed the cam towers and was surprised at the goop that came out.
Logged
No matter how many times you paint over a shadow, it's still there.
 CEO at the no kill motorcycle shop.
 You don't need a weatherman to know which way the wind blows.

Offline BenelliSEI

  • Really Old Timer ...
  • *******
  • Posts: 10,249
  • 1969 cb750
Re: CB750 K0-1
« Reply #80 on: January 21, 2025, 06:46:52 AM »
Done….. I hear you; tough choices! I know once the race season starts, I spend a lot less time on the bikes. Nice choices to have to make. Keep smiling!
Logged

Offline Don R

  • My Sandcast is a
  • Really Old Timer ...
  • *******
  • Posts: 20,197
  • Saver of unloved motorcycles.
Re: CB750 K0-1
« Reply #81 on: January 21, 2025, 11:55:37 AM »
 Agreed, I have a checklist of tests and changes our racecar needs, it was acting like it has an intake vacuum leak, I'll pull the efi and pressure test the top end. since it got the replacement CFE heads it's never really been consistent. It needs new O2 sensors in the efi and data recorder, since it burns leaded fuel, they don't last.  I got a genuine Holley one and an Ebay Bosch replacement to compare readings. The ebay one is likely a cunningly cloned china part.  I plan to put the gas carburetor back on it, or swap the efi to canned E85 fuel. 
 
Logged
No matter how many times you paint over a shadow, it's still there.
 CEO at the no kill motorcycle shop.
 You don't need a weatherman to know which way the wind blows.

Offline BenelliSEI

  • Really Old Timer ...
  • *******
  • Posts: 10,249
  • 1969 cb750
Re: CB750 K0-1
« Reply #82 on: January 21, 2025, 03:08:05 PM »
Good luck for the coming season. Our first race is the last weekend of April. I need to pull the front shocks (and remote reservoirs) and get them out to the rebuilder. The LF was leaking at the end of the season and they are overdue.
Logged

Offline Don R

  • My Sandcast is a
  • Really Old Timer ...
  • *******
  • Posts: 20,197
  • Saver of unloved motorcycles.
Re: CB750 K0-1
« Reply #83 on: January 21, 2025, 04:34:12 PM »
   Our racing association has a new schedule suited better to our location. We race at 3 of the 4 closest tracks to where we live and all of them are 1/4 mile. Most of our racers are from Chicago and Kenosha, the tracks are farther from them than from us. Byron, Cordova and Tri-States in Iowa.
  Now we'll see how excited about it my driver is, asking her about what races she wants to go to is like asking my wife where she wants to go for dinner.
Logged
No matter how many times you paint over a shadow, it's still there.
 CEO at the no kill motorcycle shop.
 You don't need a weatherman to know which way the wind blows.

Offline BenelliSEI

  • Really Old Timer ...
  • *******
  • Posts: 10,249
  • 1969 cb750
Re: CB750 K0-1
« Reply #84 on: January 21, 2025, 05:27:54 PM »
Quote from: Don R on January 21, 2025, 04:34:12 PM
   Our racing association has a new schedule suited better to our location. We race at 3 of the 4 closest tracks to where we live and all of them are 1/4 mile. Most of our racers are from Chicago and Kenosha, the tracks are farther from them than from us. Byron, Cordova and Tri-States in Iowa.
  Now we'll see how excited about it my driver is, asking her about what races she wants to go to is like asking my wife where she wants to go for dinner.

Now that made me chuckle! We have a four weekend series, each over a month apart. Every weekend is two full days of 8 hour enduros. On two of the weekends, we have an optional four hour race on the Friday afternoon, after practice. We plan on starting all of them!
Logged

Offline Don R

  • My Sandcast is a
  • Really Old Timer ...
  • *******
  • Posts: 20,197
  • Saver of unloved motorcycles.
Re: CB750 K0-1
« Reply #85 on: January 29, 2025, 11:17:29 PM »
 I'm waiting on standard piston rings from Canada. I've used them before and was pleased with the result.
Logged
No matter how many times you paint over a shadow, it's still there.
 CEO at the no kill motorcycle shop.
 You don't need a weatherman to know which way the wind blows.
Pages: 1 2 3 [4]   Go Up
« previous next »