Author Topic: Maine 78 cb750K Build - Time to get 'er back on the street!  (Read 24048 times)

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Offline Blitzburgh207

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Re: Maine 78 cb750K Build - Help me diagnose why I'm burning oil please!!
« Reply #75 on: February 27, 2013, 08:42:46 AM »
Well a yoshi kitted 550 I was going to buy sold out from under me yesterday so I'm just going to put that $$ into my motor I think.  I'm planning on putting a cheap 836 kit in it (with all the rings in the proper direction  ;) ), replacing the valve guide seals and hoping for the best.  I pretend like I need high comp pistons etc. but really I'm just commuting 80 percent of the time and being a daily rider, it sounds like the cruisinimage pistons are a good option for reliability.

Also planning on a 63A or B cam.  Not sure which yet.  And getting the machine shop to turn down a spare alternator.  I'd like to see if it will make a noticeable affect, and spending $180 to buy one online seems a little steep for what the service is...

I was going to send my head to Mr. Rieck, but I feel like if I'm going to do it, I want the stage III - which I really can't afford right now....  :( I'm taking this project one off-season at a time.  Maybe in 10 years I'll have a badass ride  8) haha

I also need to spend some time tidying up the bike.  Wiring and electrics, rearset mounts, seat mounts, and I'm going to attempt a cable actuated brake in the rear.  Hoping I can find a cable off a Kaw and make it work.  Maybe I'll get ahold of Paulages to get more info on his setup - that's pretty clean.

1978 CB750 K8

Offline Blitzburgh207

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Re: Maine 78 cb750K Build - It's cold out again...Time to wrench!
« Reply #76 on: February 27, 2013, 10:07:56 AM »
Just got off the phone with Ken at CycleX - I felt like a little schoolgirl lol.  Anyways he talked me out of a big race head he has in the used parts section and also a few big cams.  He also took a few minutes to explain to me why the 3 would be a good cam for me which was really cool of him.  How often can you call the owner of places these days and get solid personal advice.. Anyways - picking up an 836 kit shortly and hopefully be building again soon!!
1978 CB750 K8

Offline deafcaferacer

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Re: Maine 78 cb750K Build - It's cold out again...Time to wrench!
« Reply #77 on: February 27, 2013, 10:34:41 AM »
That's good news. I'm intrigued by the 836 upgrade. Please be sure to document with plenty of pictures, thanks.
'73 CB750k engine, hubs, and a '76 tank, on 'a 78 frame. Go figure.

Offline Blitzburgh207

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Re: Maine 78 cb750K Build - It's cold out again...Time to wrench!
« Reply #78 on: February 27, 2013, 03:30:53 PM »
Lost an epay bid on an 836 wiseco kit today  :'( for a brief moment I thought I could afford higher performance pistons than the cheap 836 kit....

Currently drinking away my sorrows and decided to test my bellypan vision out with photoshop.  ..I have a bunch of extra glass mat and resin. What do you guys think? Yay or nay?

1978 CB750 K8

Offline Blitzburgh207

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Re: Maine 78 cb750K Build - It's cold out again...Time to wrench!
« Reply #79 on: February 27, 2013, 04:17:44 PM »
I plan on adding a large hoop to the rear of the frame to support the seat.  I figure when I do that I can run the electrics back there independent from the fiberglass so I can take the seat on and off without a bunch of wires attached to it (it's been annoying).  Here are the two options I've been thinking w/ the lights and plate:  Help me decide!

Option A:


Option B:


I loved the tail on this Duc so I'm stealing the idea.
1978 CB750 K8

Offline Raymax

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Re: Maine 78 cb750K Build - It's cold out again...Time to wrench!
« Reply #80 on: February 27, 2013, 04:46:15 PM »
That bellypan would look really sweet. Not sure about the tail section.

I messaged CruzinImage about those 836 pistons (I'm wanting to pick up a set as well) and from what I could decipher they won't be in stock until late april.

This is what his message said:
Quote
Thank you for your question. regarding bigbore pistons kit.These were soldout.I take these pistons kit on edn of April.
Thank you again,
mitsuo
/quote]


Offline Stoli

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Re: Maine 78 cb750K Build - It's cold out again...Time to wrench!
« Reply #81 on: February 27, 2013, 04:58:40 PM »
I like Option A.

Dude you were right about the fiberglass. What a great big messy pain in the ass. One thing I learned is that the mat is more for building thickness, and if you are not making a piece from a mold, then you are better off with the cloth as your surface layer instead of the mat.

More snow piling up outside. Hope this is the last of it for this year.
My Project Threads:
Project #1 - http://forums.sohc4.net/index.php?topic=117106.0  First bike
Project #2 - http://forums.sohc4.net/index.php?topic=127364.0  Something different
Project #3 - http://forums.sohc4.net/index.php?topic=123831.0  Long and Low

Offline Blitzburgh207

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Re: Maine 78 cb750K Build - It's cold out again...Time to wrench!
« Reply #82 on: February 27, 2013, 05:06:50 PM »
That bellypan would look really sweet. Not sure about the tail section.

I messaged CruzinImage about those 836 pistons (I'm wanting to pick up a set as well) and from what I could decipher they won't be in stock until late april.


Aw man that sucks...I knew I should have bought them last week when I was looking...Damn.  I guess Ill keep an eye out on epay. Or maybe I'll continue to stick w/ stock displacement.

Thanks for the input though boys.  I'm leaning towards A as well, Stoli.

And yeah I'm glad I'm not the only one who thinks its a PITA!  I was thinking of making a female mould with plaster for the belly pan?  I feel like it would be easier and cheaper?  Then when I glass the final piece I could do a couple layers of cloth and then mat over that to strengthen it.
1978 CB750 K8

Offline Stoli

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Re: Maine 78 cb750K Build - It's cold out again...Time to wrench!
« Reply #83 on: February 27, 2013, 05:16:43 PM »
Creating a mold is a little more money but less time spent sanding. Essentially you will be sanding bondo instead of fiberglass so timewise it might be a wash since it takes time to make the mold but filling and sanding rough fiberglass takes some time as well. The cost is in the PVA and gel-coat which I think is a must if using a mold.
« Last Edit: February 27, 2013, 05:20:09 PM by Stoli »
My Project Threads:
Project #1 - http://forums.sohc4.net/index.php?topic=117106.0  First bike
Project #2 - http://forums.sohc4.net/index.php?topic=127364.0  Something different
Project #3 - http://forums.sohc4.net/index.php?topic=123831.0  Long and Low

Offline Blitzburgh207

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Re: Maine 78 cb750K Build - It's cold out again...Time to wrench!
« Reply #84 on: April 16, 2013, 10:57:38 AM »
Well it's been a while since my last update but the motor is coming along..


Fixed my fifth gear demons from last year by replacing fifth and checking for damage to the rest.  Also included the retaining rings that were left out of the last rebuild  :o oops



ART 836 kit installed.



And head cleaned and reassembled.


Now for the hard part......



It's going to take me a while to dial this in I think.  But should be back together soon!
1978 CB750 K8

Offline Blitzburgh207

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Re: Maine 78 cb750K Build - It's cold out again...Time to wrench!
« Reply #85 on: April 16, 2013, 10:58:53 AM »
Forgot to add I bought a "CX-3" cam from cycle x: equivalent to the Webcam 63A I believe.
1978 CB750 K8

Offline iron_worker

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Re: Maine 78 cb750K Build - It's cold out again...Time to wrench!
« Reply #86 on: April 16, 2013, 12:09:59 PM »
What do you mean hard part?

Once you figure out how to mount your degree wheel, build the bracket to support your dial, make some sort of piston stop or find true TDC some other way ... you're already most of the way there! Degreeing the cam in after that is easy.

Can't believe nothing went funky in your trans without those bearing retainers!  :o

Engine is looking purdy though.

IW

Offline Blitzburgh207

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Re: Maine 78 cb750K Build - It's cold out again...Time to wrench!
« Reply #87 on: April 16, 2013, 05:06:08 PM »
Oh it went funky...but after about 4.6-4.7k miles.  Shifted into 5th on the highway at about 90 passing a car and it wasn't there - just a lot of expensive sounding grinding noises  :( Thank god for parts motors!

Ran it through the gears with the cases split a few times and it seems to be working fine now.
1978 CB750 K8

Offline Blitzburgh207

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Re: Maine 78 cb750K Build - It's cold out again...Time to wrench!
« Reply #88 on: April 18, 2013, 03:39:10 PM »
Just finished degreeing in the cam  :) and I'm very pleased with the results:

Timing Card:
Intake Opens 27.5 Before TDC; Closes 43.5 After BDC
Exhaust Opens 44 Before BDC; Closes 26 After TDC

Actual Installed:
Intake Opens 27.5 Before TDC; Closes 43 After BDC
Exhaust Opens 44 Before BDC; Closes 23 After TDC

Actual lift is 0.340" vs. 0.345" advertised.

So pretty damn close. I know a lot of people have problems with the advertised numbers not being accurate.  Maybe I got lucky? Not sure if there are any real differences with the Cycle-X grind but the box for the cam says "CX-3" not "63A".

Anyways, wanted to write up my success.  Hopefully this weekend I can get some rearset mounts welded on and I'll be back on the road soon!
1978 CB750 K8

Offline 73nancy

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Re: Maine 78 cb750K Build - Time to get 'er back on the street!
« Reply #89 on: April 23, 2013, 05:23:54 PM »
looking good. I need to get mine back on the road so we can go for a ride.
k1 cb750 cafe racer (aka Helter Skelter)
k6 cb750 stock daily rider project
k3 cb750 race bike 911 big bore, alum rods, 13:1, race cam other goodies