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79 CB 750k cafe race to spring build

Willi2Villi

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First bike, first post. Let’s do this.

But let me start by saying, sorry if I get a bit long-winded. As Mark Twain once said, “I would’ve written a shorter letter if I had more time.”

Bought this bike about 10 months ago and have spent that time stopping leaks, stripping off the bullshit, pod filters and rejetting, replacing sprockets and chain, etc. And, most importantly, enjoying the riding season. Now it’s winter in Minneapolis and I say, it’s go time.

My plan is to install a regulator/rectifier and make sure all the wiring is good, get all rearsets figured out, loop the seat, get all the tabs and that extra shit all cut off there (probably just mark the tabs to be cut off later) and figure out what I’m gonna do with the battery (any suggestions on hiding it/finding a smaller one; been thinking I'd build a box and run it even with the front bar of the triangle, or cover the triangle with some kind of bulleted sheet metal).

From there, I’ll start taking this mother apart, piece by piece. Once it’s down to the frame, I’ll powder coat it and the wheels black. Like my soul. Paint the tank, headlight bucket, etc. Tear down the motor, tune it up a bit and paint it.

I’m planning on re-wiring it too, but haven’t decided when would be the best time. Rough out the harness while the bike is still assembled then finalize it after it’s all been dismantled and reassembled? God, I hate wiring.

How’s this plan sound to everyone? So far so good?
 

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And so it begins.

My dad has this super awesome shop where I’m working on my bike. Complete with everything from a TIG welder and killer stereo to a 2-hour drive to get there. Therefore, I make progress in large chunks, not the slow and steady kind.

So. I started stripping parts off and trying to get an idea of where everything fits. My freshly-lined tank is fitting nice and gold chain looking sick.

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I started messing with the rear sets, too. I’ve seen a lot of guys mount them to those rear footpeg brackets, but I’m afraid my legs might be a bit scrunched, so I’ll look into other options.

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The modified shifter should work nicely with the linkage, but not sure yet how to do the rearset on the brake side… more research needed, but I’ll probably try to avoid the original setup and just build a new link to the drum.

I have a brat seat coming in the mail and regulator/recitifier will be next. Lots of frame/battery box reconfiguring to do, but I’ll wait to do anything too final until the parts arrive. Until then, I’ll continue with plan formulation,cleaning and start rewiring (gulp).

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Soon I’ll remove the motor, clean and paint it and replace the gaskets, as I have a few little seapy leaks. The headers need a good cleanining, too. My plan is to remove as much rust as I can, then paint that Vance and Hines black. Eventually I’ll wrap the pipes too, but that doesn’t seem like something I should do until I can start the bike to heat shrink the wraps.
 
Exhaust wrap rusts the crap out of pipe to make them die much quicker. I used to sell it. Shotblast or glassbead the pipe to etch the chrome or paint will not stick for spit.

Set valves in motor using a go-to setting of .005" (.004"-.006"), they go MUCH longer between settings then and no burned valves either. The service manual says .003" and lots of problems using that as the valves burn at settings of .002". That's because what you get reading static and what bike has running are two different things, Honda didn't plan on that. Why most of these you find on the sell market run like crap, then owners tear into carbs to make it worse.
 
Thanks for the tip, amc. Have anymore before I dig into the motor for a quick tune up? I plan on otherwise tuning to manual specs, but not sure if there's any other abnormality I should be looking for, or something I should steer clear of to avoid creating major headaches for myself.
 
Electricity is hard.

Progress post. Now mostly down to the frame.. I ran out of time or i would've taken the forks off too... Trying to reconfigure all the physical components of the frame before i go too much further. I was hoping to put a brat seat on it, but I don't think it's worth reconfiguring the whole frame and risk it falling apart on me. Either I'll just do a little cafe bump, or I'm thinking about putting the seat on the bump anyways and using that space between the frame and seat as an electronics tray... Any advice on that? Would that just look stupid? Can't decide..

I'm in the progress of building new mounts for the rear sets as well. Sorry, no pictures there yet. Macgyver-ing the rear brakes is gonna be a real bitch and a half, but I have a few ideas. More to come there. Tabs marked for execution.

Also, it's hard to find anything out there about how to go about reducing or eliminating (via modern upgrades?) electrical components so they're smaller/more easily hidden. Anyone have a resource? I'd like to keep things like turn signals and eventually i'd like to install a speedo and tach, so not sure what, if anything can be eliminated. I have already installed a rectifier/regulator combo.

Looks like I'll need some new gaskets, too.... Hopefully that'll stop some of these little leaks around the heads.

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Frame mod

Got home for Christmas, so naturally, I spent every moment I could in the shop.

So... Based on little nothing more than a whim I decided to do none of the things I was previously considering doing, and instead decided to flatten by frame like all those badass SOHCs. Will the frame fall apart? Maybe. Will I die if it does? Probably. But hey, I got $55 in this seat, so let's rock n roll.

The pictures do a better job at narrating than I can, but fuck it. Let me slip into my finest Morgan Freeman voice, pour another bourbon and tell you shy people a bedtime story.

The goal here is to make the frame flat so my brat seat sits flush with the frame. But as you can see, the frame juts up just after the triangle and here's the kicker – the rear shocks mount right into that bump *whammy*

So I cut the frame where it starts bumping up, cut the braces in the front of the triangle, heated the bars, and bent them shits up to flat with that back bump. But the pipes were now too short (plot twist!) and they were jutting out at too hard of an angle to connect with the frame in the back (zing!). So i cut the brace down the middle, cut a bit out, measured once and cut twice and welded three times (joking, sorta), and bada bing bada boom, we got a flat frame.
 
I constantly wonder what the predeliction is with insisting on butchering the frames..........people just don't think they are satisfied until they do it. Often like here first bike too.
 
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Next time, feel free to offer your insight when i ask for it. This after-the-fact, wondering aloud business doesn't help anyone but yourself.

For the record, it was a lot of fun to do, and that's why I did it.
 
Its your bike man build it how you want it, just be careful when you start to cut into the structural integrity of the frame. Honda spent a lot of time and money designing and testing the stuff for strength handling and safety. As long as you understand the risk once you compromise the original design. Everyone is just trying to look out for the safety of the others on this board, some of the stuff that people do to there bikes is just awful and completely unsafe just to make it look cool. But in the end it is your bike and you can do with it as you please, just put some thought into it and make it safe. This is after all how choppers came about. so happy chopping!
 
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