"Woody" a '75 cb750k cafe racer woodgrain paint. Done 4/15!


Been Around the Block
Hey guys,

I picked up this 75 single slammer 750k for $800, it's a runner but needs a good amount of work to be where I want it. So... I decided to create a project thread and post progress along the way. I have some really cool things planned for this bike that I have yet to see on any other bike. I will have to keep those secrets for now and you can tune in to my thread to see them come to life ;). This is my first bike build so take it easy on me.


Day 1


shortly after that I took off the fender and taillight and added some drag bars


The factory coil wires were in really bad shape and had been trimmed back so many times that there was tension on the leads. I replaced the wires and caps with dyna 200 units, and lengthened the wires a few inches.




The bike was running poorly because of a cracked airbox and melted inlet stacks. Since the previous owner put 120 main jets in for the exhaust I just replaced the airbox with cheap pods. Surprisingly the bike runs much better with pods.


quick video after i put the pods on


bonus photo with some cages


So that brings us to today when my seat came in from DCC. I did some frame modification, removing the rear peg mounts and old seat mount, and rear crossbrace. I ran out of daylight so I will clean everything up tomorrow and do a bit of welding on the rear seat tubes. And I need to tighten up the chain again so I can safely ride it.





Here's a quick test mock up after trimming the front. Tomorrow I will trim the rear and weld on some hinges and mounts, and figure out where I can hide the electronics! I think the battery is going to have to stay in the current location...

Re: "Woody" a '75 cb750k cafe brat

Looking good ;D.....pm me if you are intersted in a battery idea...
Re: "Woody" a '75 cb750k cafe brat

I didn't make a whole lot of progress yesterday since I had to do some paintwork for a friend, but I fabbed up an electronics tray that goes under the seat. I'm making hinges today and I still haven't figured out exactly what to do with the battery although I have an idea for something temporary...


I'll have more updates at the end of the day.
Re: "Woody" a '75 cb750k cafe brat

After much fabrication frustration I ditched the idea of a hinged seat and just welded some studs/nuts to the frame and tank. I also made a little electronics tray to house everything under the seat. It looks a bit messy but once everything is plugged in it fits great, and I can even keep the factory oil tank for a bit longer until I make an aluminum unit with braided hoses and AN fittings. I will be making some really thin side covers to hide the tray from the sides soon too.





Re: "Woody" a '75 cb750k cafe brat

Took apart the rear end to find out there was no collar between the hub bearing and swing arm on the sprocket side. I really dont' know how the previous owner overlooked that! I didn't really want to order a new collar from honda and then wait, so I cut up an old wheel bearing and used the inner race as a collar/spacer along with a couple washers. It worked great! Since the wheel hoop was in rough shape I hit it with some black paint and polished the drum casing and threw it back on. I also removed the shock lowering blocks and put them in the factory location. Just waiting for some front caliper pads and fork seals and I'll tackle that.

Re: "Woody" a '75 cb750k cafe brat

Yes indeed. ;)

Started on the new headlight for the bike which involves 3D printing. Stay tuned!
Re: "Woody" a '75 cb750k cafe brat

Okay this is one of the unique things I'm doing to this bike that I have yet to see anyone else do. I'll preface this by saying I'm sort of an HID lighting fanatic/guru and I do a lot of projector hid retrofits for cars, maybe some of you are familiar with this?

I cut the front half off a 5.5" bmw sedan ellipsoid headlight and ditched the halogen projector, so basically all that was left was the lens, trim ring, and chrome bezel


Next, I 3d printed a tapered bucket and a front portion to mount an oem lexus rx330 xenon projector to. This projector is low beam only but is one of the best performing, widest projectors you can find. If it works out well I'll probably make a bixenon lamp to try too. Since I live in the city a high beam isn't totally necessary.

here are all the parts, you can see I overbuilt the printed parts so I could trim as necessary.




After I mount the projector to the center portion the parts will all be grafted together, bodyworked, and turned into a complete headlamp. It will be a bit longer than a traditional 7" or 5.5" headlight but I will do my best to tuck it back and make it not be an eyesore. It will all go together sort of like this: (note the projector itself is not yet inside the housing).

Re: "Woody" a '75 cb750k cafe brat

First time I've seen MakerBot in a build. Fukin love it! 8)
Re: "Woody" a '75 cb750k cafe brat

Yes, makerbot is the bees knees ;D

Got the prototyped pieces trimmed up and everything's put together. I;ll post some photos tomorrow. Any ideas what to use to finish the surface? I was thinking brushing on some fiberglass resin or gelcoat then using body filler and painting it. The printed parts are ABS.
Re: "Woody" a '75 cb750k cafe brat

Okay everything is all grafted together with the help of our friend JB. Here's some photos of it all together, it's just over 6.5" from lens to the back of the bulb, not bad.

Oh yeah, and here are some photos of the BMW headlight after removing the halogen projector:



makerbot headlight...







I need to get some kind of boot for the back too.
Re: "Woody" a '75 cb750k cafe brat

I guess this is kind of important, being an HID retrofit and all. It's an OEM phillips 85122+ (4100k) bulb.

Re: "Woody" a '75 cb750k cafe brat

I did a little research and found that ABS cement, which is basically abs particles dissolved in acetone, should be the ticket to smoothing out and strengthening the headlight housing and the best part is it's cheap and available at the hardware store. Going to give it a try ;)

Oh, as for classy, just wait til the tank and seat pan get painted! minds will be blown.
Re: "Woody" a '75 cb750k cafe brat

makerbot!! siiiiiick. the new one came out recently, i'd love to invest if i had the cash. when you look at what it does though, it's really a cheap deal innit.
signing up dude, this'll be interesting
Re: "Woody" a '75 cb750k cafe brat

Makerbot or RepRap is on my list of things to build soon... I have a large CNC router that I built a couple of years ago.. couldn't put it to much use on this build due to the one off fabicate on the fly nature of more of the parts I had to build custom.

But I would think that you are going to be pioneering how to make your parts smooth and stable for motorcycle use. I'd probably start with fiberglass resin... Then follow up with the usual body filler and such.

Watchout for the ABS cement... if you brush it over it'll make the whole part gummy til it hardens... could deform the part.... your parts are big though
Re: "Woody" a '75 cb750k cafe brat

Wow ABS cement is so awesome. I'm going to be using this stuff anytime I glue abs parts together- it's super strong and dries way fast. I coated the housing with one layer of cement and added a 2" flange off the back. I'm sure I have a spare headlight boot to cover the back I just need to dig through my parts bin. This is with one layer of the cement brushed on, I'll do another one or two then body filler then paint. I'll also epoxy some nuts into the side pegs so I have something to mount with.



(note, output photo is way underexposed)
Re: "Woody" a '75 cb750k cafe brat

OK let me get this straight...
All that for the headlight (awesome!)
but you friggin spliced the old ignition wires together? :eek:
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