Author Topic: Begining of my first project bike (78 CB750F)  (Read 10964 times)

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Offline Thor's Hammer!

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Re: Begining of my first project bike (78 CB750F)
« Reply #25 on: August 09, 2009, 10:57:35 PM »
Goals for next week:

Test compression
Adjust carbs further (manometer sync?)
check timing, points...
After confirming proper running...
Tear down to bear frame (labeling electrical connections)

1978 Honda CB750F : 2005 Kawasaki ZRX1200

Offline MCRider

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Re: Begining of my first project bike (78 CB750F)
« Reply #26 on: August 10, 2009, 05:52:50 PM »
It does help to have a theme. If the Tracy body isn't your style let it go. The bike in my Avatar built in 1972 has a Tracy 2 piece on it. The tank size is the same as the 1 piece body and Tracy made the seats in either solo or 2 up and I had the 2 up. Sure it got some looks. But as a practical matter that sub 2.5 gallon gas tank was a real PIA.

Anything on a frame can be fixed by a decent welder and not too much money. My project has proven that to me. I've seen you looking at my build thread, so maybe you've seen that my frame is missing that triangle behind the coils...as well as the lower frame rails. This was common to do to 750s as it allows you to work on the engine without pulling it.

Are you missing the lower rails as well? Many just ran their bikes without, but APE made a replacement rail kit and Gordon on this site made/makes an even better one. As far as I'm concened with the replacement kits, you'd be back in business. They bolt in and out.

You won't be seeing me bolt my rails back in till i get the engine in, but you can easily see they are missing now.

PS: That stocker you posted earlier is way nice. I could never do that as I have to twist it a little my way. But I still like practicality and usefullness.  Just me.

« Last Edit: August 10, 2009, 06:30:47 PM by MCRider »
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1988 NT650 HawkGT;  1978 CB400 Hawk;  1975 CB750F -Free Bird; 1968 CB77 Super Hawk -Ticker;  Phaedrus 1972 CB750K2- Build Thread
"Sometimes the light's all shining on me, other times I can barely see, lately it appears to me, what a long, strange trip its been."

Offline kerryb

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Re: Begining of my first project bike (78 CB750F)
« Reply #27 on: August 10, 2009, 08:02:43 PM »


I tried to figure out pictures from the help screen...no luck,  I had to quess.  Will these help?
« Last Edit: August 10, 2009, 08:06:42 PM by kerryb »
intrigued by the wail...seduced by the scream.

Offline Thor's Hammer!

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Re: Begining of my first project bike (78 CB750F)
« Reply #28 on: August 10, 2009, 08:15:37 PM »


I tried to figure out pictures from the help screen...no luck,  I had to quess.  Will these help?


KerryB...dude....that rear section would be perfect man!!

It is exactly what I need.  It looks like you already cut it off the frame from the second pic?

Am I correct?


1978 Honda CB750F : 2005 Kawasaki ZRX1200

Offline kerryb

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Re: Begining of my first project bike (78 CB750F)
« Reply #29 on: August 10, 2009, 08:50:28 PM »
Yeah, it's cut off already.  I'll try to take some better pics to use for further weight reduction.  Your welder can cut the pieces off to suit his needs instead of me guessing on the cuts.  To reduce shipping costs I'll remove a little more, wait for my pics.  Just to be sure, is a '78k frame the same as a '78F frame in this area?  Are the seat mounts and lock bracket in the same location?
intrigued by the wail...seduced by the scream.

Offline Thor's Hammer!

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Re: Begining of my first project bike (78 CB750F)
« Reply #30 on: August 10, 2009, 09:13:28 PM »
Yeah, it's cut off already.  I'll try to take some better pics to use for further weight reduction.  Your welder can cut the pieces off to suit his needs instead of me guessing on the cuts.  To reduce shipping costs I'll remove a little more, wait for my pics.  Just to be sure, is a '78k frame the same as a '78F frame in this area?  Are the seat mounts and lock bracket in the same location?


I am pretty sure what you have is an exact match to my frame.  Some of the pics from my WTB thread were not a match for what it looks like on my frame where there is left over material from removal...your pics look exactly as I would expect mine to look if the brackets were still there.  The key to me knowing was the placements of the seat lock bracket...it is the longest of the brackets and the on the same side as a big piece of material on my own frame.

I wouldn't mind having the rear most cross bracket as well as mine is sort of hacked up when the PO cut off the rear tubes...it's not crucial, but would be nice.

« Last Edit: August 10, 2009, 09:18:27 PM by mismith356 »
1978 Honda CB750F : 2005 Kawasaki ZRX1200

Offline Thor's Hammer!

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Re: Begining of my first project bike (78 CB750F)
« Reply #31 on: August 10, 2009, 09:35:14 PM »
It does help to have a theme. If the Tracy body isn't your style let it go. The bike in my Avatar built in 1972 has a Tracy 2 piece on it. The tank size is the same as the 1 piece body and Tracy made the seats in either solo or 2 up and I had the 2 up. Sure it got some looks. But as a practical matter that sub 2.5 gallon gas tank was a real PIA.

Anything on a frame can be fixed by a decent welder and not too much money. My project has proven that to me. I've seen you looking at my build thread, so maybe you've seen that my frame is missing that triangle behind the coils...as well as the lower frame rails. This was common to do to 750s as it allows you to work on the engine without pulling it.

Are you missing the lower rails as well? Many just ran their bikes without, but APE made a replacement rail kit and Gordon on this site made/makes an even better one. As far as I'm concened with the replacement kits, you'd be back in business. They bolt in and out.

You won't be seeing me bolt my rails back in till i get the engine in, but you can easily see they are missing now.

PS: That stocker you posted earlier is way nice. I could never do that as I have to twist it a little my way. But I still like practicality and usefullness.  Just me.



Thanks MCRider,

You're correct, I was admiring you project thread.  Lots of great info there and I love the pics and details you provided along the way.  Very nice project thread man!

The Tracey body kit (if that's what it was) is now sold.  Was totally not my sort of things.  Call me weird, but I seem to gravitate towards the stock look with bikes.  I love the old KZs in close to stock form and I like the look of the 78 CB750F in stock dress as my inspiration pic shows.  My ZRX is nearly stock as well, largely because I liked the GPz bikes so much, I wanted the ZRX the way it comes.

I know the factory look isn't for everyone or even for most...but I like the original styling.

 
1978 Honda CB750F : 2005 Kawasaki ZRX1200

Offline Thor's Hammer!

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Re: Begining of my first project bike (78 CB750F)
« Reply #32 on: August 24, 2009, 12:10:11 PM »
Real quick update:

Received carb rebuilt kits, front and rear master cylinder rebuild kits and caliper seals, clips and dust covers...all honda oem.

I found out one of the front caliper pistons is really hosed...now need to get another one.  Have yet to get to rear caliper yet, so I'm gonna wait on ordering till I know about that first.

Also need 4 rubber insulators for the carbs before I can get the bike running with the rebuilt carbs.

Headed to a ZRX Rally in N. GA..here soon, so no updates for a while to come.

QUESTION:  If I type this out in a forum thread, but nobody reads it, does that mean it isn't really happening ?

 ::) ::)

 
1978 Honda CB750F : 2005 Kawasaki ZRX1200

Offline KB02

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Re: Begining of my first project bike (78 CB750F)
« Reply #33 on: August 24, 2009, 05:55:51 PM »
QUESTION:  If I type this out in a forum thread, but nobody reads it, does that mean it isn't really happening ?

 ::) ::)

I keep asking myself the same question...  ;)

You just have to have confidence that, not only are you doing it, but people are reading it.

That's what I keep telling myself, 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"

Offline Thor's Hammer!

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Re: Begining of my first project bike (78 CB750F)
« Reply #34 on: September 15, 2009, 01:42:09 PM »
Well...been off the project for a while now.  Went up to ride the Dragon and some other choice roads in N GA.

Am back now and have most of the replacement o-rings for the carb rebuild.  Need to get some yammy carb dip and a good assembly/exploded diagram of the carbs.

Maybe this weekend I'll get to it.

1978 Honda CB750F : 2005 Kawasaki ZRX1200

Offline Thor's Hammer!

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Re: Begining of my first project bike (78 CB750F)
« Reply #35 on: October 21, 2009, 08:14:10 PM »
Long time no update:

Grabbed some yammy carb dip a couple weeks back, and just tonight started soaking carb #1.  Also soaking blinker ears in vinegar to remove the rust.  They are pretty bad, but I am hopeful.

 

1978 Honda CB750F : 2005 Kawasaki ZRX1200

Offline kerryb

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Re: Begining of my first project bike (78 CB750F)
« Reply #36 on: October 25, 2009, 06:46:43 AM »
We're still out here reading....did you get your frame fixed up yet...when do we get to see pictures?
intrigued by the wail...seduced by the scream.

Offline Thor's Hammer!

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Re: Begining of my first project bike (78 CB750F)
« Reply #37 on: December 30, 2009, 09:25:16 AM »
Well....not much "real" progress...but I have chased my tail a little bit if anyone is interested in that?

I rebuilt the year and model correct carbs which i bought off a member here...horribly dirty carbs.  I installed them on the bike, not knowing I had disconnected the coils and reconnected them backwards....yollow wires should go to yellow wires right...not yellow to blue damn it!....anyway....the bike wouldn't start with newly rebuilt carbs.  I got frustrated, which i should have controlled better...figured to hell with getting it running right before tearing it down (lots of folks start with a DOA bike and end up with a beautiful outcome, right?) to send to powder coat and paint.  The coils are all that kept the rebuilt carbs from working but I wasn't thinking clearly and went in the wrong direction.

I took the carbs off, and pulled the wire harness and some other bits off the bike that same day...don't work on your bike when frustrated!!  After that, I left the bike alone for a week or two and cooled down....realized I was being foolish in not getting it running properly, test ridding it, making sure the gears in the trans were all good and to then and only then, tear it down for paint and powder.

So after re-evaluating where I was going, I went ahead and put the bike back together, with some help in other posted threads, I got the electrical and coil issues resolved and the bike now runs (not perfectly though) on the correct PD-42A carbs.

I got a good tank for $75 from ebay.  Also bought a really ratty seat for a decent price, but it had a bad seat pan and unusable foam (both only evident after closer review once in hand).

Just bought a set of front calipers off ebay ($41) as I have a bad piston in one of mine and these were cheaper than buying a new piston.

Bought a compression tester and an impact screw driver/extracter for xmas so I will be testing compression this weekend.

Trying to buy a seat in better condition from a board member here, but funds are extremely tight right now though and I might not be able to afford it...we'll see.

That's it in a not so small nut shell.  I tend to be too verbose...wish i had the talent for "economy in words"  :-[
« Last Edit: December 30, 2009, 10:17:05 AM by mismith356 »
1978 Honda CB750F : 2005 Kawasaki ZRX1200

Offline Flying J

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Re: Begining of my first project bike (78 CB750F)
« Reply #38 on: December 30, 2009, 11:08:45 AM »
My recovered stock seat is still up for grabs.

Offline Thor's Hammer!

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Re: Begining of my first project bike (78 CB750F)
« Reply #39 on: December 30, 2009, 04:02:50 PM »
PM'd ya bro ;)
1978 Honda CB750F : 2005 Kawasaki ZRX1200

Offline Thor's Hammer!

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Re: Begining of my first project bike (78 CB750F)
« Reply #40 on: January 24, 2010, 04:37:14 PM »
It's been a while since the last update, haven't done a lot, but made some minor progress.

Bought a seat for a good price from a member here on the board.  It has a decent seat bad and cover it good enough to get me by until after paint work is complete.  Tank from epay doesn't seem to have any leaks and petcock seems not to leak.

Have had the bike running a couple of times with the Keihin PD-42A carbs and while they were only bench sync'd, all cylinders are firing and exhaust gas headers are all hot, although not equally...indicating a sync is needed at the minimum.

The epay calipers for $41 may have been money wasted.  They look good on the outside, but the pistons were VERY corroded under the dust boots and i may not even be able to remove the pistons....I may have to go with the grease gun mentod...but I suspect the pistons will be pitted as they have the appearance of the cheap aftermarket pistons which are known to pit very easily as I understand it.  Looks like I am going to need pistons before I can take the bike out on it's maiden shake down voyage....#$%^&* me.

Here are so pics of the "new", likely worthless calipers:

[img width= height=]http://lh5.ggpht.com/_ZG4HknndfT8/S1zdG5l5-0I/AAAAAAAABDg/g3mSGpfwtGE/s800/P1150983.JPG[/img]



This weekend I replaced most of the multi-plug connectors with new ones from OMP.

Here are some pics of the new electrical plugs and couple of the bike as sits today:

31 years of abuse:

[img width= height=]http://lh5.ggpht.com/_ZG4HknndfT8/S1zdKvvaeyI/AAAAAAAABD8/Oy6LDxbh2L0/s800/P1150971.JPG[/img]



Silicon Rectifier harness was by far the worst...here it is after new connectors and plugs, plus lots of Di-Electric Grease.

I tested the rectifier for continuity and it tested fine, so I hopefully I am good...we'll see if the battery recharges.

[img width= height=]http://lh6.ggpht.com/_ZG4HknndfT8/S1zdJyXWf2I/AAAAAAAABD0/8GVEOISTrHk/s800/P1150974.JPG[/img]



Starter connectors...again, LOTS of Di-Electric Grease.

[img width= height=]http://lh6.ggpht.com/_ZG4HknndfT8/S1zdKL0Zj_I/AAAAAAAABD4/Rcj4waVQ76Q/s800/P1150973.JPG[/img]



Here are some mock up pics...still a long ways from doing a full tear down...but there is at least some (albeit minor!!) progress.

[img width= height=]http://lh6.ggpht.com/_ZG4HknndfT8/S1zdHu3_WOI/AAAAAAAABDk/AmI76DcgPdE/s800/P1150982.JPG[/img]




[img width= height=]http://lh4.ggpht.com/_ZG4HknndfT8/S1zdIbiqvzI/AAAAAAAABDo/W14QHDj23r4/s800/P1150981.JPG[/img]



[img width= height=]http://lh6.ggpht.com/_ZG4HknndfT8/S1zdJgJLp1I/AAAAAAAABDs/za44ePGf7MI/s800/P1150980.JPG[/img]



Next steps needs to be brakes, gas tank rubber, then welding of the seat hinge bracket (removed by PO for Tracey Style body kit).

That's it for now.
1978 Honda CB750F : 2005 Kawasaki ZRX1200