1980 Honda CB750K Cafe Build

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1980 Honda CB750K Cafe Build

CBGirl
I am new to all things "motorcycle". My fiance and i work on Toyota and Jeep rock crawlers, but i decided i wanted a project of my own and a new hobby to lean. I am sure i could have picked something a lot easier and cheaper to satisfy myself, but i have always wanted a bike and why not learn everything i can by building one of my own.

This past weekend i bought a Honda CB750K for under 300 bucks. It has not run in about two years, but overall it seems to be in pretty great condition. I spent the weekend cleaning the carbs, removing the tank, installing new battery, flushing the old oil and giving it an overall quick clean. I am now stuck waiting for a custom cafe style tank and replacement OEM spin on filter.

I am 5'2 and this bike is big and heavy. So i plan on shaving down the seat, getting shorty shocks, and cutting the spring in the forks so i can at least get my feet flat on the ground. My goal for this bike is to build a cafe racer. I've got a lot to learn, but i am hoping that i can find help and advice from you guys here.

Stay Tuned.




Am i a Tom Boy? If that means that my daddy taught me to throw a ball, change the oil, shoot a gun, and whoop your ass, then yes.
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Re: 1980 Honda CB750K Cafe Build

tjurek51
i'm new to the CB750 world as well.  have a mint condition 1980 SS, but my goal, like yours, is to build a cafe racer.  My plan is to build one on the cb1000 platform.  at 6'7", i won't have your challenges, but i would like to keep track of what you're doing, lessons learned, etc.  things like where you place your foot holds and linkage to get the racing stance.  also, are you planning to extend the rear wheel in addition to the cut downs, etc.?  if ok with you, can you share with me any resources/research you find on how to design this type of bike, parts, etc.?  thanks.
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Re: 1980 Honda CB750K Cafe Build

Truck
In reply to this post by CBGirl
Nice starter bike, welcome to the club!

Just some advice on springs. If you are going to the effort of changing them go with progressives. The ride will be well worth the extra money. Also be careful when lowering the bike, if you go to low you will have to modify the kick stand.
It's only illegal if you get caught.

If at first you don't succeed, use more lighter fluid

95% of Harley Davidsons ever made are still on the road... The other 5% made it home.

New Baltimore, Va '82 CB900c, 1980 CB985F/K 'Mutt"
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Re: 1980 Honda CB750K Cafe Build

CBGirl
In reply to this post by tjurek51
Awesome, Yeah you definitely won't have the height/weight restrictions i have to figure out haha. I plan on sharing all of those things! Because this is my first bike i plan on doing a lot of research before cutting into the bike and hopefully getting a parts bike so that i can make mistakes on that one first.
Am i a Tom Boy? If that means that my daddy taught me to throw a ball, change the oil, shoot a gun, and whoop your ass, then yes.
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Re: 1980 Honda CB750K Cafe Build

CBGirl
In reply to this post by Truck
Thanks for the advice, Truck! I will probably need to lower it too low, but i am concerned about not only modifying the kick stand, but also ground clearance.  
Am i a Tom Boy? If that means that my daddy taught me to throw a ball, change the oil, shoot a gun, and whoop your ass, then yes.
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Re: 1980 Honda CB750K Cafe Build

Truck
I put 11.5" progressives on the rear. plenty of ground clearance and lowered the bike nicely. I did have to have about 2" taken out of the stand, I just went to a welder, had him cut a section out of the middle and weld the end back on.

These bikes take a little tinkering to get right, but once you do they run forever. and we also have great people on here for all the advice you could need.
It's only illegal if you get caught.

If at first you don't succeed, use more lighter fluid

95% of Harley Davidsons ever made are still on the road... The other 5% made it home.

New Baltimore, Va '82 CB900c, 1980 CB985F/K 'Mutt"
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Re: 1980 Honda CB750K Cafe Build

CBGirl
That sounds like what i need to do! Thank you. I have heard really great things about these bikes and i am really excited.
Am i a Tom Boy? If that means that my daddy taught me to throw a ball, change the oil, shoot a gun, and whoop your ass, then yes.
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Re: 1980 Honda CB750K Cafe Build

Re-run
Administrator
In reply to this post by CBGirl
Careful with the new tanks if they are fiberglass. Without a good liner, they usually suffer from ethanol laced fuels. Leaks are pretty common.

I don't know how much luck you will have with flat footing, but with a cut down seat and short shocks, you should be able to drop about 4 inches on the seat height. Down to about 27 or so inches.

For the front, you might want to look into shorter forks. Shorter springs would just cause the forks to bottom easily.
http://www.frankmain.qpg.com Probably the best forks you will find. Don't know the cost anymore though.
You may be able to contact cyclexchange.net and they might be able to make shorter forks as well.
The ride IS the adventure. The destination is just to get gas!
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Re: 1980 Honda CB750K Cafe Build

CBGirl
Re-run, i got a aluminum gas tank to lighten up the bike a little bit. So hopefully i wont have any leaks. Thanks for the advice, i have heard great things about Franks forks.
Am i a Tom Boy? If that means that my daddy taught me to throw a ball, change the oil, shoot a gun, and whoop your ass, then yes.
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Re: 1980 Honda CB750K Cafe Build

TOOLS1
Administrator
Here is a link to a writeup on how to properly shorten front forks. http://honda-cb750-s.456789.n3.nabble.com/How-to-shorten-forks-td4042465.html
TOOLS
Life is not about the number of breaths, you take, but the moments that take your breath away.
I don't have an anger problem. I have an idiot problem. Hank Hill
Never confuse education for intelligence.
Happiness is a belt fed weapon.
I just can't imagine what could go wrong.
No fire? No explosions? So whats the point of your story?
Those who are too smart to engage in politics are punished by being governed by those who are dumber. ~Plato
It couldn't be done, but the darn fool didn't know it, and did it anyway.
We all got problems. Ksharp
I like vintage bikes because they take me away from the clutter of technology that I work with everyday and back to a simpler time of mechanical elegance and simplicity.. "ninadm"
Darkwing Duck: The worst part of public transportation is the Public.
"That is awesome shit there" Re-Run
"Fear nothing, attack everything" Eric Berry
" Oh, you read that on the internet? Clearly it IS a massive problem. Of course it CAN’t be normal operation."

1976 CB 750-A X 2
1977 CB 750-A X 4
1977 CB 750-K
1976 CB 750 F
1981 CB 750
1966 Kawasaki SG 250
1981 KZ 750 LTD
1973 CB 350
1979 CM 185 Twinstar
1982 Honda XL 80
South of Eden (Kansas City MO)
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Re: 1980 Honda CB750K Cafe Build

CBGirl
Tools, i found your thread already! I have it saved for when i do that this weekend. Looks like a very simple fix. Thanks for the easy to follow instructions.
Am i a Tom Boy? If that means that my daddy taught me to throw a ball, change the oil, shoot a gun, and whoop your ass, then yes.
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Re: 1980 Honda CB750K Cafe Build

Truck
Just remember one important thing while working on your bike - pics are like crack on this site, click away!
It's only illegal if you get caught.

If at first you don't succeed, use more lighter fluid

95% of Harley Davidsons ever made are still on the road... The other 5% made it home.

New Baltimore, Va '82 CB900c, 1980 CB985F/K 'Mutt"
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Re: 1980 Honda CB750K Cafe Build

CBGirl
I definitely will!!




Am i a Tom Boy? If that means that my daddy taught me to throw a ball, change the oil, shoot a gun, and whoop your ass, then yes.
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Re: 1980 Honda CB750K Cafe Build

CBGirl
In reply to this post by Truck
Got my oil filter in finally, but I am having problems with everything else. The previous owner messed around with the wiring harness and I haven't figured out where everything's supposed to go. So far when I hook the battery up I get zilch.

Can anyone tell me what this is?



image1.JPG (521K) Download Attachment
image2.JPG (390K) Download Attachment
Am i a Tom Boy? If that means that my daddy taught me to throw a ball, change the oil, shoot a gun, and whoop your ass, then yes.
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Re: 1980 Honda CB750K Cafe Build

TOOLS1
Administrator
The first is an aftermarket spin on oil filter, the second looks like the turn signal flasher. As for not getting any juice, there is a main fuse mounted to the starter solenoid. It is a thin metal strip hidden under a rubber cap. I replace them with the wire in blade type fuse holders. I also use a blade type circuit breaker instead of a fuse.
TOOLS
Life is not about the number of breaths, you take, but the moments that take your breath away.
I don't have an anger problem. I have an idiot problem. Hank Hill
Never confuse education for intelligence.
Happiness is a belt fed weapon.
I just can't imagine what could go wrong.
No fire? No explosions? So whats the point of your story?
Those who are too smart to engage in politics are punished by being governed by those who are dumber. ~Plato
It couldn't be done, but the darn fool didn't know it, and did it anyway.
We all got problems. Ksharp
I like vintage bikes because they take me away from the clutter of technology that I work with everyday and back to a simpler time of mechanical elegance and simplicity.. "ninadm"
Darkwing Duck: The worst part of public transportation is the Public.
"That is awesome shit there" Re-Run
"Fear nothing, attack everything" Eric Berry
" Oh, you read that on the internet? Clearly it IS a massive problem. Of course it CAN’t be normal operation."

1976 CB 750-A X 2
1977 CB 750-A X 4
1977 CB 750-K
1976 CB 750 F
1981 CB 750
1966 Kawasaki SG 250
1981 KZ 750 LTD
1973 CB 350
1979 CM 185 Twinstar
1982 Honda XL 80
South of Eden (Kansas City MO)
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Re: 1980 Honda CB750K Cafe Build

CBGirl
Thank you!! That's the oil filter I just replaced. I just posted using my phone so it put both photos at the bottom! It worked though! I have juice... Now I think I need to replace my starter.




image1.JPG (344K) Download Attachment
Am i a Tom Boy? If that means that my daddy taught me to throw a ball, change the oil, shoot a gun, and whoop your ass, then yes.
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Re: 1980 Honda CB750K Cafe Build

TOOLS1
Administrator
Try jumping across your solenoid with a screwdriver, or other piece of metal before replacing the starter. It might be your starter button is bad. That is very common.
TOOLS
Life is not about the number of breaths, you take, but the moments that take your breath away.
I don't have an anger problem. I have an idiot problem. Hank Hill
Never confuse education for intelligence.
Happiness is a belt fed weapon.
I just can't imagine what could go wrong.
No fire? No explosions? So whats the point of your story?
Those who are too smart to engage in politics are punished by being governed by those who are dumber. ~Plato
It couldn't be done, but the darn fool didn't know it, and did it anyway.
We all got problems. Ksharp
I like vintage bikes because they take me away from the clutter of technology that I work with everyday and back to a simpler time of mechanical elegance and simplicity.. "ninadm"
Darkwing Duck: The worst part of public transportation is the Public.
"That is awesome shit there" Re-Run
"Fear nothing, attack everything" Eric Berry
" Oh, you read that on the internet? Clearly it IS a massive problem. Of course it CAN’t be normal operation."

1976 CB 750-A X 2
1977 CB 750-A X 4
1977 CB 750-K
1976 CB 750 F
1981 CB 750
1966 Kawasaki SG 250
1981 KZ 750 LTD
1973 CB 350
1979 CM 185 Twinstar
1982 Honda XL 80
South of Eden (Kansas City MO)
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Re: 1980 Honda CB750K Cafe Build

CBGirl
I will definitely try that. Thanks. If the starter is bad do you know anyone who carries aftermarket starter motors? Or do you think I would just have to have it rebuilt.?
Thanks,

Am i a Tom Boy? If that means that my daddy taught me to throw a ball, change the oil, shoot a gun, and whoop your ass, then yes.
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Re: 1980 Honda CB750K Cafe Build

shinyribs
Administrator
I'm not sure how I missed this.

Welcome to the forum. Your ol' girl needs some love, but it's sounds like she is in good hands now! I'm pretty anxious to see what you've got as far as the aluminum tank you mentioned.

Guess I'll just be hanging out waiting for updates.

Oh, the starter. If yours doesn't check out I'd be tempted to look on ebay. You can get a starter for a 900 (buddy did this recently and is real happy with it- if you're interested I can get details) and it'll crank the bike much quicker. Though, to be honest, I don't see any issues with the 750 starter all. Anyway, they rarely ever fail, so buying one off of a part-out bike wouldn't scare me. Just have to be careful shopping, but since you're a lady you have that intuition thing going for you.

To answer you, I'm not aware of any aftermarket starters. Rebuilding may be something you can do yourself.Check it out in the FSM. IIRC, there should be a set of brushes in there. If your windings are healthy, putting in new brushes is silly easy.I just cant recall if these starters are of this type or not, but the FSM will know.  Good luck!
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Re: 1980 Honda CB750K Cafe Build

shinyribs
Administrator
oh, btw....the next time you are tossing up pics...some of us might be real interested in seeing those rock crawlers ya'll are putting together.
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