Author Topic: Dirty Old K1  (Read 5270 times)

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Offline G3

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Re: Dirty Old K1
« Reply #25 on: December 28, 2013, 11:14:57 am »
Engine overhaul continues.  The cylinder head is out at a machine shop to have a twisted off exhaust bolt extracted.  I've been spending time cleaning up the pistons and installing new rings.  The carbon was thicker and more tightly adhered than I had previously thought.  It took some scraping with a painters 6 in 1 tool, sanding with emery cloth, and burnishing with a Dremel.

Ring installation was a learning experience.  The diagram below describes how to install rings in a straightforward and simple way.  You will recognize the top compression ring by the shiny bevels around the edges.  I installed them with the makers mark up as many forums insist must be done, but couldn't find any official direction on this.  I believe it's a pretty forgiving system and the ring would perform fine if installed either direction.  The second compression ring is recognizably square and just a tiny bit thicker by about .001".  It doesn't have the recognizable bevel like the top ring.  Again, I installed it with the makers mark up, but again, couldn't find any technical guidance for this.  The RIK rings I used have directions for the installation of the 3 piece oil scraper on the back of the packaging.

Offline G3

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Re: Dirty Old K1
« Reply #26 on: May 15, 2014, 03:37:03 pm »
I'm having problems getting the cylinders over the pistons and new rings.  #2 and 3 go in slick as a whistle, but #1 or 4 always gets cocked and bound in the process.  I've had pretty good luck just pressing the rings with my fingers to get them up into the bevel and into the cylinder until the last one...

Any expert opinions on solutions?  Non-experts may also weigh in.  Thanks!

Offline Tews19

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Re: Dirty Old K1
« Reply #27 on: May 18, 2014, 06:31:18 pm »
Try the popsicle trick. It will level out pistons 2 and 3 to get them in first. There is a video on YouTube where a guy did it on his 550 engine. 
1969 Honda CB750... Basket case
1970 Honda CB750 survivor.

Offline goldarrow

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Re: Dirty Old K1
« Reply #28 on: May 18, 2014, 08:01:11 pm »

Try the popsicle trick. It will level out pistons 2 and 3 to get them in first. There is a video on YouTube where a guy did it on his 550 engine.

Can you elaborate? Or post a link?
Life Is Full Of Challenges - And My Backyard Is Full Of SOHC4's

CB550 K0
CB750 K0, K2, K23 JDM, K45, K5
And the little ones z50r, xr50r, st90


750k5 http://forums.sohc4.net/index.php?topic=114817.0

Offline G3

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Re: Dirty Old K1
« Reply #29 on: July 05, 2014, 05:30:35 pm »
Build update:

The engine is back together.  After several tries at installing the cylinders, I discovered that there was so much carbon in the ring grooves that the new rings couldn't compress far enough to get the cylinders down.  Lesson learned from this:  don't use the spark advance nut to turn the engine--when something jams up in there, you will snap off the advance shaft.  Believe me on this one.  Use the nut on the generator instead.

Used the "engine laying on it's side" technique to install the motor in the frame.  It was super easy.  I recommend it if you're stripped down far enough to handle the frame.

Pics of current status attached.  Can anyone direct me to a purveyor of something similar to the rusty baffles shown.  They came out of the header shown.

Thanks for looking!

Offline Tews19

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Re: Dirty Old K1
« Reply #30 on: July 06, 2014, 01:59:13 pm »
Can't help with the exhaust but glad you have made progress and shared it with the community. 
1969 Honda CB750... Basket case
1970 Honda CB750 survivor.

Offline G3

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Re: Dirty Old K1
« Reply #31 on: July 16, 2014, 06:33:53 pm »
Still trying to figure out the maker of the 4-2 megaphones that came with the bike so I can get some baffles that fit.  I have attached a couple of better pics after they have been installed (and an extra shot that I really like).

I've been in touch with MAC.  They say they're Kerkers.  And I've been in touch with Supertrapp (Kerker).  They say they're MAC.

Anyone care to take a guess?  You can't do any worse than the "professionals".

Offline goldarrow

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Re: Dirty Old K1
« Reply #32 on: July 16, 2014, 07:49:48 pm »
I'm never right, so I'm going to guess those pipes are jardine
Life Is Full Of Challenges - And My Backyard Is Full Of SOHC4's

CB550 K0
CB750 K0, K2, K23 JDM, K45, K5
And the little ones z50r, xr50r, st90


750k5 http://forums.sohc4.net/index.php?topic=114817.0

Offline Tews19

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Re: Dirty Old K1
« Reply #33 on: July 17, 2014, 04:25:08 pm »
Those do look like Jardines. 
1969 Honda CB750... Basket case
1970 Honda CB750 survivor.

Offline Stev-o

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Re: Dirty Old K1
« Reply #34 on: August 21, 2014, 05:53:40 am »
Def not Kerkers
'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

Offline 754

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Re: Dirty Old K1
« Reply #35 on: August 21, 2014, 02:51:33 pm »
Look like Jardines.   Baffles look ok, just fix the belled end part.
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Offline G3

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Re: Dirty Old K1
« Reply #36 on: September 07, 2014, 07:48:05 pm »
Pretty much done here.  Fired it today.  Runs a little rough but I'm sure air/fuel mix and carb sync will remedy that.  Front brake seems to be not releasing completely.  Don't know what's up there.  Still haven't found baffles to fit those megaphones.  That also probably contributes to the rough running. 

Anyway, it turned out pretty nice if I do say so myself.  Thanks, everyone.

Offline MoMo

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Re: Dirty Old K1
« Reply #37 on: September 08, 2014, 03:19:45 am »
Nice restomod.  Is the color reddish/orange?...Larry

Offline G3

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Re: Dirty Old K1
« Reply #38 on: September 08, 2014, 04:20:51 am »
Thanks, Larry.  Yes the color is red but it looks a little orange depending on the light.  Not bad considering I took it into the shop looking for a budget paint job.  The guy asked me what color I wanted it and I told him "whatever color you're shooting next.'"

Offline MoMo

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Re: Dirty Old K1
« Reply #39 on: September 08, 2014, 05:21:22 am »
Thanks, Larry.  Yes the color is red but it looks a little orange depending on the light.  Not bad considering I took it into the shop looking for a budget paint job.  The guy asked me what color I wanted it and I told him "whatever color you're shooting next.'"



Had a friend do the same thing as that and his bike turned out great too, luck of the color draw I guess...Larry

Offline 70CB750

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Re: Dirty Old K1
« Reply #40 on: September 08, 2014, 05:27:59 am »
Thanks, Larry.  Yes the color is red but it looks a little orange depending on the light.  Not bad considering I took it into the shop looking for a budget paint job.  The guy asked me what color I wanted it and I told him "whatever color you're shooting next.'"

You lucky they did not have Mary Kay Cadillac next  ;D

Nice color this one!