Author Topic: 1975 CB750F - Project Yellow Jacket (Read 60140 times)

DollarBill · « **on:** October 12, 2008, 08:39:00 PM »

Here we go... Saw this bike on CL for $600 on a Thursday, called the guy to ask some basic questions and he wanted $650 for it. I ended up not going to look at it because of other obligations and assumed it would be gone. Saw posted again the following week and he dropped the price to $450. I took that as a sign from the Old Honda gods that I must buy it....regardless of female spousal units disgust. I had been looking for a 400F and a guy at the hospital where I work has had one sitting in his garage for over 10 years. I was sooooo close to talking him out of it and his brother, I don't know his name but I like to call him A-hole, talked him into keeping it....and it will probably sit another ten years. Too bad...poor little bike. I have a 73 350 Twin that I love and wanted to graduate to the 400f before tackling a 750...oh well. I live in the sticks so it's not often you find what you want close to home. I don't know what it is about old Honda's but they are hard to find in Texas. When I look at eBay it seems like everything is in the Northeastern states. I wonder if it's because you have longer winters so more bikes get forgotten in sheds? Down here you can ride almost year 'round...some people do.

This bike sat in a shed/carport for 7 years and came with 7 years of saw dust, dirt, and mud dobber nests. The story goes that a kid in the neighborhood gave it to the old guy in exchange for some musical equipment/instruments. The kid put a new battery in it before trading it and connected the pos/neg to the opposite posts and thus melted the harness. It never moved again.

I've been thinking about trying to fix this harness and it was suggested by more than one of you in another thread I started about the harness but after removing it from the bike have decided its not worth it. This thing is crispy almost all the way up and the large connectors are all melted. I'll have to find a good used one or adapt another year model. You can't find a 75/76 super sport NOS harness.

So my initial list to do is get the bike running. Feel free to add to my TODO list...
1. New harness
2. New rectifier (old one looks like it's been in an oven)
3. Clean carbs
4. New battery
5. New plugs
5. New fuel lines - One actually had a spent rifle casing stuffed into it where it broke. That was an interesting find.
6. New oil and filter

I think that might be enough to try and start it???

Alright photo monkeys (I include myself in that group) here's the first batch.

DollarBill · « **Reply #1 on:** October 12, 2008, 08:44:37 PM »

Why am I calling it Project Yellow Jacket you ask?

I never saw these guys until after I took the water hose to it for the first time. They survived the trailer ride home...er to their death I should say. I have never gotten along well with Yellow Jackets as they always seem to seek me out and sneak attack. Mean little f**kers!

I am thinking of a gold and black theme here.

DollarBill · « **Reply #2 on:** October 12, 2008, 09:00:24 PM »

Off with the tank....seat....wiring harness....carbs. The airfilter was NASTY and the foam just melts in your fingers when you touch it. From what I can see on K models the airbox is hidden much better than on the super sports. Thoughts on keeping the stock airbox as opposed to pods or stacks? I like the way stacks and pods look but hate messing with jetting adjustments. This will be a cafe...how cliche huh? I just love the old racer looks as opposed to modern sport bikes. However, the Ducati SportClassic Sport 1000S is pretty bangin!! I'd also like to see the new Norton come to life but I won't hold my breath.

Love the muffler on this thing...HA it looks like the glass pack off of an old truck was welded on the headers.

Some other general photos to remind me of how it dirty and crusty it was.

DollarBill · « **Reply #3 on:** October 12, 2008, 09:03:39 PM »

Now for melted stuff...

DollarBill · « **Reply #4 on:** October 12, 2008, 09:06:06 PM »

And a few more for posterity.

DollarBill · « **Reply #5 on:** October 12, 2008, 09:12:00 PM »

Initial look at the carbs was encouraging. I really expected them to look like poo had been run through them. #1 and #2 look pretty clean with no varnish in the bowls at all. I'll take photos of the bowls tomorrow. #3 has some flaky looking crap in it but not terrible. #4 found the poo! this one is dark and dingy and closer to what I expected of the others. Speaking of poo...I took my kids to the park today and had to take my daughter to the restroom and someone had rubbed human feces all over the sink, spout, and handles. What the hell is wrong with people???

DollarBill · « **Reply #6 on:** October 12, 2008, 09:24:31 PM »

So there it is folks the beginning of a long long process. I wish I could work on it all the time and bang this out in 8-12 weeks but that's just a dream.

Thanks in advance for help, advice, and the occasional kick in the pants throughout this project. Right now I'm going to go out to the garage and stare at it for a while and dream about what it could be.

fuzzybutt · « **Reply #7 on:** October 12, 2008, 11:35:19 PM »

i'm wondering is a fuse on the positive battery cable, like alot of modern bikes, would prevent that from happening. i know it saved my ass at the triumph dealer when i was uncrating and prepping speed triples.

Hush · « **Reply #8 on:** October 13, 2008, 02:03:38 AM »

Ah crispy fried wiring....delicious.

Still looks like the good bones of a project bike.
Harnesses are not that hard to make, I've seen some done on here and taken mine back to nothing to retape it from end to end.
As you are doing a cafe anyway why not abrieviate some of the wiring loom?

DollarBill · « **Reply #9 on:** October 13, 2008, 04:32:03 AM »

I've thought about abbreviating but what should I cut out that isn't necessary? Just the indicator lights on the "dash"? What else can go away?

AK Cafe · « **Reply #10 on:** October 13, 2008, 09:16:46 PM »

Ah yes! Dirt dobber's and yellow jackets, two of the things that I Don't miss about Texas! Along with Rattle Snakes and Mesquite bushes.

Looks like a fun project! Keep us posted.
AK Cafe

DollarBill · « **Reply #11 on:** October 14, 2008, 08:24:30 PM »

Here's the photo of the float bowls before cleaning

Good Lord the SOHC4 Carbs have a lot of little pieces. Here they are taking a bath in Simple Green

All the pieces back out of the bath and getting ready to start reassembly

KB02 · « **Reply #12 on:** October 15, 2008, 04:45:29 AM »

That's about how my work bench looked when I took apart my carbs. Theres a lot a little parts that go into those.

andy750 · « **Reply #13 on:** October 15, 2008, 05:42:04 AM »

Great photos and looks like you are making good headway. Love the orange colour of the bike and too bad about the crushed tank. I think you got a great deal though - not too crusty at all. Im looking forward to seeing how this goes....and I would buy a new harness if I were you...partsnmore or DSS have them....much easier and less hassle troubleshooting electrical problems...keep in mind the ignition barrel may be crap and the connector at the back always jiggles loose so make sure thats secure when you finally come to put it all back together.

good luck!
Andy

DollarBill · « **Reply #14 on:** October 15, 2008, 06:41:49 AM »

I need a bigger work bench!

Thanks Andy, I will be needing a new ignition switch because the plastic on this one disintegrated when I unplugged it. I think the tank may just be my first foray into metal working unless I can get away with a steal on eBay.

I found a used 75 SS wiring harness in Colorado and will be ordering that today.

RM81 · « **Reply #15 on:** October 15, 2008, 09:40:26 AM »

This should be a good thread to follow. Good luck on the rebuild.

DollarBill · « **Reply #16 on:** October 16, 2008, 09:26:54 PM »

Still working on the putting the carbs back together and cleaning them up. In the meantime browsing the wonderful forums here I came across this thread about Hayashi Mags: http://forums.sohc4.net/index.php?topic=38004.0

That's like metal porn. Since I don't have a measly $2500 laying around for a pair I started looking for something similar but different than comstars. Enter recent Nighthawk wheels. Does anyone know if these will fit on a CB750? The fronts are 18" and the rear is 17" I believe???

Now put on your imagination cap and picture these powder coated gold with a polished aluminum shoulder....

KB02 · « **Reply #17 on:** October 17, 2008, 04:41:48 AM »

Quote from: DollarBill on October 16, 2008, 09:26:54 PM

Still working on the putting the carbs back together and cleaning them up. In the meantime browsing the wonderful forums here I came across this thread about Hayashi Mags: http://forums.sohc4.net/index.php?topic=38004.0

That's like metal porn. Since I don't have a measly $2500 laying around for a pair I started looking for something similar but different than comstars. Enter recent Nighthawk wheels. Does anyone know if these will fit on a CB750? The fronts are 18" and the rear is 17" I believe???

Now put on your imagination cap and picture these powder coated gold with a polished aluminum shoulder....

Mmmmmmm....... Thinking cap likey...

Will they fit? As a direct bolt on, I highly doubt it. BUT anything can be Made to fit with a little time, energy, money, lathe, mill, drill press... etc...

I first looked for a Nighthawk for the wheels and tires on my K8 project. I found a Katana first, though, at the right price. I'm making those tires fit, so I don't see why you won't be able to make the Hawk's sneakers sit in place.

DollarBill · « **Reply #18 on:** October 17, 2008, 06:33:41 AM »

It looks like this model of Nighthawk 91-92 used a drum brake in the rear so I would probably have to lose the disk in the back... Of course there is a pair of Hayashis listed on eBay this morning with a starting bid of $999. I remember the look my wife gave me when I brought home Cobra rims for my mustang....she then promptly cut a telephone pole in half with that car. Yeah....I think I will stay away from the Hayashis...

DollarBill · « **Reply #19 on:** October 17, 2008, 02:01:13 PM »

KB08....just read your entire project thread. You are making some stuff "fit" for sure. I like those Katana wheels too! The deeper I get into this the more I see LOTS of new tools in my future. Here's the short list:

1. New air compressor
2. Welding equipment
3. Drill press
4. Paint kit - I'd love to do more than rattle can
5. Powder coating equipment
6. Old oven for the above
7. Motorcycle lift

KB02 · « **Reply #20 on:** October 18, 2008, 05:22:24 AM »

Quote from: DollarBill on October 17, 2008, 02:01:13 PM

KB08....just read your entire project thread. You are making some stuff "fit" for sure. I like those Katana wheels too! The deeper I get into this the more I see LOTS of new tools in my future. Here's the short list:

1. New air compressor
2. Welding equipment
3. Drill press
4. Paint kit - I'd love to do more than rattle can
5. Powder coating equipment
6. Old oven for the above
7. Motorcycle lift

8.) 3 in 1 Drill, Mill, Lathe...

DollarBill · « **Reply #21 on:** October 18, 2008, 05:57:21 AM »

Right...how could I forget the 3-in-1??? Now I just need to make a few bucks to pay for all this stuff...not to mention the parts for the bike. I'm a web/graphic designer in real life and only pretend to be a motorcycle mechanic/custom bike builder in here so if anyone needs a website or some cool graphic design holler at me. That I can definitely do...God only knows how this bike is going to turn out

You can see some of my work over at http://www.hamiltondesigns.com

DollarBill · « **Reply #22 on:** October 20, 2008, 08:44:55 PM »

Son of a.... You can NEVER take enough photos is the lesson I am learning right now. I took the carbs apart laid them out neatly in what I thought was an organized manner but let a few days go by and WHAM you won't remember a thing. What I am having trouble finding a home for is this little washer:

I looked in the blown apart parts manual and the shop manual and I can't find where this little guy goes. TAKE MORE BEFORE, DURING, AND AFTER PHOTOS!

On another note I got my new/old wiring harness in the mail today and I learned another lesson. When ordering something over the phone ask VERY specific questions. I asked about the condition of the harness and the response I got was VERY GOOD...no cut wires...complete. He failed to mention that the plastic connectors were crap.

I looked at connector kits online at Z1 and Vintage Connections and their harness rebuild kits are pretty expensive and they didn't have in stock the connectors I needed so I just bought another old harness. Does anyone else know a source for these connectors?

I also discovered why that spent shell casing was stuffed in the fuel line on the petcock; this isn't the stock petcock. This petcock has two fuel outlets and from what I can tell the original had a single outlet. Can anyone confirm this? Also can anyone suggest a good aftermarket petcock that will work? The prices for used petcocks and NOS seem ridiculous to me.

...AND I can't believe it but I found a picture of EXACTLY what I was talking about doing with Nighthawk wheels....gold...and I think it looks AWESOME!!! Gotta love the Internet!!!

By the way the shell casing has a 54 on it...never heard of a .54....

Jerry Rxman Griffin aka MuthaF'er · « **Reply #23 on:** October 20, 2008, 09:57:49 PM »

The correct petcock has only 1 outlet.

See if this carb diagram helps.

Go to www.Electrexusa.com
Perhaps they can supply a few connectors for you.

DollarBill · « **Reply #24 on:** October 21, 2008, 06:34:17 AM »

Thanks Jerry, that is exactly what I needed! Do you or anyone else in here have any experience with the combination regulator/rectifier aftermarket units? Are they worth it? The one below is from the website you sent me electrosport.com

Product Description:
This regulator/rectifier replaces both the original rectifier bridge on the Honda CB four-cylinder models, as well as the mechanical regulator. Both are replaced with this single modern solid state regulator/rectifier. You will see more stable voltage output at the battery compared to using the outdated OE components. Warranty: one year

News:

Author Topic: 1975 CB750F - Project Yellow Jacket (Read 60140 times)

fuzzybutt

AK Cafe