Author Topic: 1978 CB750K Cafe Resurrection  (Read 4251 times)

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Offline Amphibious

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1978 CB750K Cafe Resurrection
« on: February 21, 2010, 04:39:33 PM »
So where to start....   I picked up the donor bike Dec 2009 from a driveway in Parksville, BC.  this bike had been sitting outside, in Coastal weather for a few years.  the previous owner had even removed the old plugs for me!  how nice of him.  so salty air and lots of rain had locked the pistons up tight.  the damage to the luggage rack and gauges was due to the roof it was parked under collapsing on it during a freak island snow-storm.  oh well, price was right and I wanted to do a ground up Cafe build.


















one night after way to many coffee's and a rather heated discusion about work with my boss, I decided to both rearange my garage and tear down the bike.  by 0400, it looked like this...



after a week of soaking in WD40, and with the liberal use of a rubber mallet, the pistons were free!


Offline Amphibious

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Re: 1978 CB750K Cafe Resurrection
« Reply #1 on: February 21, 2010, 04:46:02 PM »
So the idea for this build is loosely based on Carpy's "Black Venom":

http://www.cb750cafe.com/bikes.php?cat=1&id=32&PHPSESSID=2f880ba74aec88c7e3fff43c09a8cc72

I'll be modifying the stock tank just like his, and picking up one of his 78K seats and his 4:1 pipes on my trip to California in march.

the rims and spokes were rusted to hell, so after a chat with procycle in Oregon, I've got some Aluminum Excell rims and SS Spokes on the way.

all the electrical and batt will go under the seat, and will be replacing the stock oil tank with one from BCR.  Pods on the carbs.

currently breaking down the engine for sandblasting and new seals all around.  have to get the pistons and barrels inspected to see where I go from there....

Pics as they come...

Offline KB02

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Re: 1978 CB750K Cafe Resurrection
« Reply #2 on: February 22, 2010, 04:20:25 AM »
Looks like we starter in similar places.  ;D Here's mine when I started (also a K8):



have the cylinders checked out good. With the cast iron sleeves, the rust tends to worm it's way into the cylinder wall. With the amount of rust you have i there, you're probably looked at a bore job to get it all out anyway. But, you might be luck, too, and get away with just a light bore and oversized rings.

Keep us up to date on what you've got going on. I love seeing projects start out.
« Last Edit: February 22, 2010, 04:21:57 AM by KB02 »
1978 CB750K Project
2000 Ducati ST2
...and a pedal bike

Join the AMA today!!

My project thread Part I: K8 Project "Parts Bike"
My project thread Part II: Finishing (yeah, right) touches on Project "Parts Bike"

Offline Amphibious

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Re: 1978 CB750K Cafe Resurrection
« Reply #3 on: February 22, 2010, 05:29:48 PM »
thanks for the vote of confidence!  I've been following your build for some time now, great work.  it gives me hope!

finally separated the head today.  now to find a shop that can tell me what I'm dealing with... and whether I should get the barrels done before or after I sand blast & Paint...








Offline KB02

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Re: 1978 CB750K Cafe Resurrection
« Reply #4 on: February 23, 2010, 04:37:34 AM »
... and whether I should get the barrels done before or after I sand blast & Paint...\

After. Why risk possible damage to machined surface from paint or sand.

That's my thought anyway.
1978 CB750K Project
2000 Ducati ST2
...and a pedal bike

Join the AMA today!!

My project thread Part I: K8 Project "Parts Bike"
My project thread Part II: Finishing (yeah, right) touches on Project "Parts Bike"

traveler

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Re: 1978 CB750K Cafe Resurrection
« Reply #5 on: February 23, 2010, 04:45:06 AM »
Just my .02

Bore them out.  The rust is heavy....and you have to get down to a surface that is perfect and smooth.  Might as well make her an 836. :-\

Head to Mike (MReick) for a stage 3 job.  With the Carpy/Yoshi pipe and some carb work, it'll run strong.

Undercut the tranny gears while it's apart.

Again, just my PERSONAL view

BTW, good luck on the project!  Looks good so far!

~Joe
« Last Edit: February 23, 2010, 04:48:15 AM by traveler »

Offline Amphibious

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Re: 1978 CB750K Cafe Resurrection
« Reply #6 on: March 14, 2010, 01:42:52 PM »
update!  Good News.... Bad News....

the Good News first!  I found a set of Jugs and pistons on ebay for a $50, look in excellent shape, come from an engine with <8000mi on it.  will save me piles of $ vs. a 836 kit and reboring.

The Bad news!  after a botched attempt to send them via fedex, I'm sending them USPS, $95 in shipping later....

oh yeah, and it looks like I'm moving to Haiti for 12mths at the end of the month for a job, so this project will gather dust for another year...