Author Topic: CB750 K3F - AKA The Red  (Read 118602 times)

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Offline 70CB750

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Re: CB750 K3F - AKA The Red
« Reply #400 on: September 09, 2015, 05:04:13 AM »
Dorothy donated rectifier and regulator.  Red charges much better.

Also swapped oil presure gauges from Dorothy to Red, it looked like Red has lower pressure in idle but turned out it was just the gauge.

Offline Kickstart

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Re: CB750 K3F - AKA The Red
« Reply #401 on: September 09, 2015, 11:49:01 AM »
Finally getting caught up on this thread... good progress on dialing her in!

Keep us posted when you put the neutral arm stopper back in.  Hopefully everything just needed a good flushing.


- Chris
75' CB750F Orange flake (rider)
75' CB750F Blue (Project)
75' CB750F Painted black (Project)
No Reserve Racing #171 AHRMA

Offline 70CB750

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Re: CB750 K3F - AKA The Red
« Reply #402 on: September 09, 2015, 03:16:19 PM »
Thank you.

I certainly hope that few hundred miles and increased zddp  is all she needs to fix the shifting for good.

Offline 70CB750

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Re: CB750 K3F - AKA The Red
« Reply #403 on: September 18, 2015, 03:13:58 AM »
800 miles and oil change, not the first one, she had like 200 miles on her before I split the engine again.

Anyway, oil clean, nothing bad coming out, magnets on the oil filter cartridge had only small amount of very very fine ferrous material - I presume from rings/cylinders.

Offline 70CB750

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Re: CB750 K3F - AKA The Red
« Reply #404 on: September 22, 2015, 04:04:11 AM »
Took apart el cheapo feelers and made me a tappet measurement tool.  I should have done it long time ago, much easier to use.

I made two of the same to fight back that german who always hides #$%* on me  ;D

Offline Kickstart

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Re: CB750 K3F - AKA The Red
« Reply #405 on: September 22, 2015, 07:40:58 PM »
Nice!

I have a bunch of the cheap ones in my tool drawer.  I should say I have a bunch of mostly broken cheap ones in my tool drawer as they never last that long for me.
- Chris
75' CB750F Orange flake (rider)
75' CB750F Blue (Project)
75' CB750F Painted black (Project)
No Reserve Racing #171 AHRMA

Offline 70CB750

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Re: CB750 K3F - AKA The Red
« Reply #406 on: September 23, 2015, 02:51:32 AM »
Thanks :)

With the oil change I also installed back the transmission Neutral arm, 800 miles without it definitelly smoothed things out, in fact the shifting was gettting clunky from low resistance.  It felt like gear jump in too fast and not smoothly because of the low resistance.

Anyway, took her out and she shifts like a charm, smooth, precise, Neutral is much easier to find.

Also adjusted rear brake, tried it very lightly at first but looks like the one piston F rear caliper is not capable of locking the wheel.  It is better brake than the drum, but only little bit.

Offline 70CB750

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Re: CB750 K3F - AKA The Red
« Reply #407 on: December 12, 2015, 10:33:56 AM »
Using F top bracket makes it hard to get key in and turn it.  I have one key with ground head to fit, but this new key I just made works and looks  better.
« Last Edit: March 14, 2016, 04:17:41 AM by 70CB750 »

Offline 70CB750

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Re: CB750 K3F - AKA The Red
« Reply #408 on: April 27, 2016, 04:56:40 AM »
I lost brake light, dang, that makes me nervous rider.

Rear brake and front brake are both using the same make of  pressure switch, the rear brake stopped working first, now the front is gonne too.  I guess it is time to try different brand, annoying.

Offline Kickstart

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Re: CB750 K3F - AKA The Red
« Reply #409 on: April 27, 2016, 06:22:20 PM »
Surprising to hear that both failed... what brand/part?  Were they aftermarket repro's of the Honda part or just some other npt hydraulic pressure switch?

Might not be a bad idea to use an spring loaded regular mechanical switch for the rear.  At least something different so you reduce the probability of simultaneous failures.  I also like to set the rear pedal switch to light up the brake light before any braking pressure starts, so I can flash tailgaters  without any braking.
- Chris
75' CB750F Orange flake (rider)
75' CB750F Blue (Project)
75' CB750F Painted black (Project)
No Reserve Racing #171 AHRMA

Offline 70CB750

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Re: CB750 K3F - AKA The Red
« Reply #410 on: April 28, 2016, 04:10:51 AM »
Surprising to hear that both failed... what brand/part?  Were they aftermarket repro's of the Honda part or just some other npt hydraulic pressure switch?

Might not be a bad idea to use an spring loaded regular mechanical switch for the rear.  At least something different so you reduce the probability of simultaneous failures.  I also like to set the rear pedal switch to light up the brake light before any braking pressure starts, so I can flash tailgaters  without any braking.

You have a point there, Chris.  It was some sale at Superstore, not sure of the brand.    I am getting Goodridge to replace them, it was the brand I had on my list on the begining, I just went cheap.  I will see how they hold, technically I can use original K rear switch, since the pedal and frame are K3.

Offline 70CB750

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Re: CB750 K3F - AKA The Red
« Reply #411 on: June 07, 2016, 03:42:39 AM »
Replaced break switches with Goodridge, finally, both front and back. 

Offline 70CB750

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Re: CB750 K3F - AKA The Red
« Reply #412 on: August 03, 2016, 03:02:19 PM »
I had a decent front tire from Dorothy with only 6000 miles on it, got a matching rear tire and put them on Red.

It sucks to have older sister, doesn't it?

Funny moment, took it for a spin to find out that I installed the speedo cable without the core, because the core was bathing in oil  ;D

Offline 70CB750

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Re: CB750 K3F - AKA The Red
« Reply #413 on: August 08, 2016, 05:53:23 AM »
The new rear tire is 110 unlike that old Dunlop that was 120.  Wow, how nimble she feels now.

After research and measurements I decided to run sans tubes on Comstar wheels.  I am using NAPA metal valves.  Even newly mounted tubeless tire is hard to unseat when deflated and other people reported many safe miles on Comstars without tubes.

Offline 70CB750

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Re: CB750 K3F - AKA The Red
« Reply #414 on: August 08, 2016, 07:13:55 AM »
I had a spare set of foot pegs - so I hacked them to fit to the frame for the passenger, much better than the original flimsy set. 

Offline 70CB750

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Re: CB750 K3F - AKA The Red
« Reply #415 on: January 16, 2017, 05:13:39 AM »
Red's engine back on the stand.

Offline Stev-o

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Re: CB750 K3F - AKA The Red
« Reply #416 on: January 16, 2017, 07:11:24 AM »
Whats the plan, Prokop?
'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

Offline 70CB750

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Re: CB750 K3F - AKA The Red
« Reply #417 on: January 16, 2017, 10:15:58 AM »
Replace the cam tensioner. It could be one  of those vintagecb750 bad ones.

Debating about the cam chain replacement.

What do you think?

Offline MoMo

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Re: CB750 K3F - AKA The Red
« Reply #418 on: January 16, 2017, 05:13:18 PM »
Replace the cam tensioner. It could be one  of those vintagecb750 bad ones.

Debating about the cam chain replacement.

What do you think?




that far apart, may as well

Offline Stev-o

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Re: CB750 K3F - AKA The Red
« Reply #419 on: January 17, 2017, 07:14:55 AM »
Replace the cam tensioner. It could be one  of those vintagecb750 bad ones.

Debating about the cam chain replacement.

What do you think?




that far apart, may as well

Agreed
'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

Offline 70CB750

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Re: CB750 K3F - AKA The Red
« Reply #420 on: January 19, 2017, 05:00:08 PM »
Looks like this wheel is like new after 5000 miles.

Offline 70CB750

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Re: CB750 K3F - AKA The Red
« Reply #421 on: January 19, 2017, 05:01:59 PM »
She is getting fancy upgrade anyway :)

Offline 70CB750

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Re: CB750 K3F - AKA The Red
« Reply #422 on: January 19, 2017, 05:05:11 PM »
Red suffered from oil tank draining, used Elan's kit to rebuild the oil pump.  The shaft seal inside the pump, what a pain to get out  :(

Offline 70CB750

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Re: CB750 K3F - AKA The Red
« Reply #423 on: January 31, 2017, 04:17:51 AM »
D.I.D. cam chain from Kenosha Kid ;)

Offline 70CB750

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Re: CB750 K3F - AKA The Red
« Reply #424 on: February 19, 2017, 05:13:08 AM »
Replacing cam chain, ugh.