Author Topic: Project bobber build 70' cb750 four (Read 28323 times)

750four · « **on:** June 26, 2009, 08:20:16 PM »

Just picked up a heck of a deal on a 1970 cb750. Going hardtail and lowered fork on top of firestone 4.00's. At least thats the plan today. I was lead to believe that this was a well running bike that was just parked and forgotten about for 5 years. Charging up a new battery right now. But looking at the cluster of spliced and chopped wires I can tell the electrical will be a chore.

Is there any way to bypass everything except the ignition? So I can get it running, not sure if there are any sensors or whatnot

I'm not putting the turn signals back in. Just a head light and a brake/tail light. Getting rid of the dummy lights and the gauges for now.
Can't wait to cut the back half off this thing!!!

zoo mob · « **Reply #1 on:** June 27, 2009, 12:48:24 AM »

Lets see some pics, got to say that with the prices K0's are bringing and how damn cool they look, it might be worth considering keeping it stock. Best of luck and have fun with whatever you choose.

750four · « **Reply #2 on:** June 27, 2009, 07:09:47 AM »

I'll post up pics after I get it cleaned up a little. The bike's actually titled a 1970, but the motor is a k1. It's not clean enough to do a full resto unless I had a ton of money and time. I don't have much of both so this will be my porject for the summer.

Beans · « **Reply #3 on:** June 27, 2009, 04:59:21 PM »

Where are the pics.

750four · « **Reply #4 on:** June 28, 2009, 02:18:35 PM »

Here are a few pics after I pulled the skin back. My electrical is toast. Wondering if I can just start from the battery go to the key, then ignition. Then run my head light and brake switch.

Thats the parts pile that I'll have to ebay. Tank and side panels are in good shape. The hippie starburst paint might make them worth a bit more?!!...

Beans · « **Reply #5 on:** June 28, 2009, 02:21:20 PM »

Pic not working for me.

Roach Carver · « **Reply #6 on:** June 28, 2009, 03:01:45 PM »

the wiring can be a bit tricky due to the charging system. the abreviated wiring diagram may be available here, but i am almost positive that it is posted over at the honda chopper forum. try this.

http://s119.photobucket.com/albums/o131/jay_sco/bike%20stuff/?action=view&current=simple_wiring_diagram2.jpg

750four · « **Reply #7 on:** June 28, 2009, 03:39:44 PM »

Quote from: 71cb750 on June 28, 2009, 03:01:45 PM

the wiring can be a bit tricky due to the charging system. the abreviated wiring diagram may be available here, but i am almost positive that it is posted over at the honda chopper forum. try this.

http://s119.photobucket.com/albums/o131/jay_sco/bike%20stuff/?action=view&current=simple_wiring_diagram2.jpg

That's a really good link. Nothing helps put things into perspective like cartoon drawling. Seriously though that does help a lot.

Shenanigans · « **Reply #8 on:** June 28, 2009, 04:02:54 PM »

You sure that its a 1970? I thought those were the later side covers?

Roach Carver · « **Reply #9 on:** June 28, 2009, 04:08:31 PM »

the seat latch is early style- 69,70, maybe 71. I think?

that the 69 was the only model with the sidecovers with the screens. 70 would be with the next style.. again I think.

someone will chime in I am sure.

750four · « **Reply #10 on:** June 28, 2009, 06:55:09 PM »

It's titled as a 1970, but the panels aren't the original. They're the burnt orange color on the back side of the side panel. Not sure what year they're from?

andy750 · « **Reply #11 on:** June 28, 2009, 08:28:34 PM »

Looks like a 73 or 74....your wiring harness is not 70/71 but more like a 73/74. Tank is pre-74. Emblems are 74+. Blinkers are 75+. Front brake is a 73+ as it has the rainguard. What does the VIN plate say?

Let me know when you put the tank/sidecovers up for auction as I am interested. Any rust/dents in the tank and any cracks in the sidecovers?

cheers
Andy

750four · « **Reply #12 on:** June 29, 2009, 05:57:46 PM »

vin # cb750 1003695 per the head tube and the title. PM me if you're interested in the side panels or tank. The side panels are primo aside from the paint. Good plastic and all of the tabs are intact. Tank is good too. No dents and very little surface rust in little spots, will need relined though. Cap functions well and still shines up.

andy750 · « **Reply #13 on:** June 29, 2009, 06:11:43 PM »

PM sent about the sidecovers. Ill pass on the tank if it needs relined.

cheers
Andy

750four · « **Reply #14 on:** July 09, 2009, 07:55:18 PM »

Getting the wheels powdered black and my Firestones are bout to be ordered. Plus picking up some new pionts and electronics.O also picked up a new pair of oem honda fork gaitors for the sohc cb750's, new in the pack.

Check out this crazy sohc chopper. What a sound!! I spy the cycle x manifold/2 carb setup, Hot cam you think?

[youtube=425,350]<object width="425" height="344"><param name="movie" value="

name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="

type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="425" height="344"></embed></object>[/youtube]

750four · « **Reply #15 on:** July 12, 2009, 03:15:25 PM »

Getting a little excited waiting on my wheels and tires to be finished up. So I threw on my new tank and one of my fork gaitors to see where I'm at. I am going to chop the 2 front support bars and exstend the backbone down to the bottom of the frame. The rear upper stays will Y out from the back bone. This should give me enough room to drop the rear of the tank an 1" or so. It looks like I'll definitly have to stretch it a bit. Not to much though, I'm 5"10 and will be running straight bars with a little back sweep. Maybe 2-3" I want to keep the aggresive look. Going to be super low. As low as I can get away with. Lowering the forks too.
Anyone running a 4" or wider crosswidth tire up front, will it fit?
Tips to lowering forks?
What's the most common stretch length? with the battery box and oil tank in the rear.

Here's a coupl of pics:

Don R · « **Reply #16 on:** July 12, 2009, 05:57:10 PM »

Before you put the saw to the frame you might check to see if anyone is looking for one, that is a real early frame number. You might be able to trade up and get some parts or cash difference to boot,
Also you can hot wire from the battery to the black/white wire to the coils to get power there. jumper to the solenoid to spin it over and it should run. be careful there are no clutch or neutral safetys.

cdoggy81 · « **Reply #17 on:** July 14, 2009, 07:44:19 PM »

Looking forward to seeing this. Keep up the good work!

750four · « **Reply #18 on:** August 02, 2009, 11:23:35 AM »

Wheels are back from powder caoting, new bearings too. Tires should be on by end of next week. Here's a mock up of what I am thinking. 5" stretch/ 5" off the dirt.

^jockey shifter in progress^

750four · « **Reply #19 on:** August 06, 2009, 07:26:59 AM »

Tires made it in yesterday and got them mounted to the wheels. Looks awesome! Can't wait til I get time to stick them on the bike. I went 4.0 front and 4.5 rear Firestone deluxe champions. After that it's off to the shop so I can do the hardtail. Shifter was welded up and mounted, but not sure if I like the flat look of it.

The_Crippler · « **Reply #20 on:** August 06, 2009, 09:19:39 AM »

As much as I love the look of the brass knuckles on the jockey shift, I can see those helping to make the other name for it more true: Suicide shift.
You need to be quick when running one of those, and I can see your fingers getting snagged in those holes at just the wrong moment.

But otherwise, I dig it. Choppers are often not meant for a daily ride, but as a work of art.

750four · « **Reply #21 on:** August 07, 2009, 06:07:04 PM »

cafeconleche · « **Reply #22 on:** August 07, 2009, 07:41:54 PM »

love those tires!

750four · « **Reply #23 on:** August 22, 2009, 05:45:01 PM »

Lowered the forks, replaced the fork oil, and added the cyclex fork boots. Got the drag bars from cyclex also, plus my 3" seat springs, and a throttle. Found a set of velocity stacks that should work. Currently waiting on some tubing then the real work begins.
Very pleased how well and easy these forks cleaned up and were modified.

750four · « **Reply #24 on:** August 23, 2009, 07:11:03 PM »

Quote from: 71cb500kid on August 23, 2009, 06:25:09 PM

So sick.. how did you lower the forks? Do you lose ridablilty?

http://forums.sohc4.net/index.php?topic=57043.msg617273#msg617273

So far I went just 2". Might try lower after the hardtail. This is pretty simple and very cheap. PM me if you have any questions.

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Author Topic: Project bobber build 70' cb750 four (Read 28323 times)