Author Topic: 1976 CB750F, for my pops. (Read 3606 times)

MrLonghorn · « **on:** July 08, 2016, 07:30:58 AM »

So, my dad decided to officially retire. And I decided to build him a motorbike as a retirement gift.

Enter this titled, running CB750.

Hope to have the bike completed within a month or two.

Plans are to give it a basic tune-up, clean and paint, etc. I am still debating on whether or not I want to swap out the tank/seat. That particular tank has about 10 pounds of bondo, I reckon.

hashvm · « **Reply #1 on:** July 08, 2016, 07:37:06 AM »

It looks good .. Great start for a good cause

SOHC4 Cafe Racer Fan · « **Reply #2 on:** July 08, 2016, 10:23:38 AM »

Great that you started with a titled, running bike.

I'm not sure what your plans are -- restoration, restomod, etc.

The tank's knee indents could use some refinement and the seat could definitely use more padding - your dad might like that.

calj737 · « **Reply #3 on:** July 08, 2016, 10:37:17 AM »

Quote from: CB750 Cafe Racer Fan on July 08, 2016, 10:23:38 AM

...and the seat could definitely use more padding - your dad will definitely appreciate that.

Said the father of 4

MrLonghorn · « **Reply #4 on:** August 10, 2016, 09:46:25 AM »

I have been slowly trudging along with the 750. Picked up a new seat, as well as a slew of other parts.

Tires:

Finned Points Cover:

New seat, with one of the two tanks I am going to run.

The other tank option (which doesn't work as well with the front of the seat and will give me petcock issues):

I am also considering running a GL1000 rear fender:

SOHC4 Cafe Racer Fan · « **Reply #5 on:** August 10, 2016, 10:32:23 AM »

You previously stated the bike was titled and running. How does it run and does it have any leak issues? If it runs well and has no leaks, that's a huge bonus. How are the brakes and suspension?

Using the existing F model tank will be easier since it has no fitment or petcock clearance issues.

The new seat will require you to modify/flatten the frame hoop but it's definitely an improvement comfort-wise. A rear outer fender might be a good idea especially if dad rides in the wet (it will keep a wet dirty trail off his back). A rear inner fender is a must (to keep the same off your motor and electrical components.

s10hornet · « **Reply #6 on:** August 10, 2016, 10:57:13 AM »

I also have a 76 cb750f that I cafe'd. The one thing I will advise is that you get rid of the cheapo pods and get a stock airbox.
I tried mine with pods(and I used K&N) but just couldn't get it to run right. I had rebuilt the carbs and a friend who is a longtime motorcycle mechanic tuned them for me. With the pods the throttle response was sorely lacking. I switched back to the stock airbox with a K&N filter and the difference was amazing.

70CB750 · « **Reply #7 on:** August 11, 2016, 04:16:49 AM »

Following

MrLonghorn · « **Reply #8 on:** August 11, 2016, 05:26:05 AM »

Quote from: CB750 Cafe Racer Fan on August 10, 2016, 10:32:23 AM

How does it run and does it have any leak issues? If it runs well and has no leaks, that's a huge bonus. How are the brakes and suspension?

The new seat will require you to modify/flatten the frame hoop.

A rear outer fender might be a good idea especially if dad rides in the wet (it will keep a wet dirty trail off his back). A rear inner fender is a must.

No leaks, runs as good as it can without a proper airbox (which I am probably going to change), Upgraded front master with SS line. I am in the process of rebuilding the front caliper. I also just rebuilt the front forks (cleaned, new seals, oil, etc).

Instead of modifying the frame hoop, I am going to modify the ABS plastic seat.

I have a modified inner fender in place already, and the more I look at it the more I think I am going to run that rear fender.

SOHC4 Cafe Racer Fan · « **Reply #9 on:** August 11, 2016, 06:24:15 AM »

Quote from: MrLonghorn on August 11, 2016, 05:26:05 AM

Quote from: CB750 Cafe Racer Fan on August 10, 2016, 10:32:23 AM
How does it run and does it have any leak issues? If it runs well and has no leaks, that's a huge bonus. How are the brakes and suspension?

The new seat will require you to modify/flatten the frame hoop.

A rear outer fender might be a good idea especially if dad rides in the wet (it will keep a wet dirty trail off his back). A rear inner fender is a must.

No leaks, runs as good as it can without a proper airbox (which I am probably going to change), Upgraded front master with SS line. I am in the process of rebuilding the front caliper. I also just rebuilt the front forks (cleaned, new seals, oil, etc).

Instead of modifying the frame hoop, I am going to modify the ABS plastic seat.

I have a modified inner fender in place already, and the more I look at it the more I think I am going to run that rear fender.

Good news and good progress.

GV1390 · « **Reply #10 on:** August 11, 2016, 06:42:44 AM »

Neat! Keep at it man.

MrLonghorn · « **Reply #11 on:** August 23, 2016, 09:46:07 AM »

New tires mounted. Front brake rebuilt and bled. Rear brake bled. Getting closer to having a rideable motorbike.

Need to get the rear fender mounted and figure out a tail light.

Soon it will be ready for a shakedown run.

mitch5069 · « **Reply #12 on:** August 23, 2016, 07:47:54 PM »

Is the seat custom or did you buy it somewhere?

MrLonghorn · « **Reply #13 on:** August 25, 2016, 10:24:47 AM »

I am considering this paint scheme, thoughts?

SOHC4 Cafe Racer Fan · « **Reply #14 on:** August 25, 2016, 02:58:21 PM »

Black with white pin line evokes vintage BMW. Perhaps limit the pin to 1 line.

TomsK8resto · « **Reply #15 on:** August 25, 2016, 04:12:13 PM »

Quote from: MrLonghorn on August 25, 2016, 10:24:47 AM

I am considering this paint scheme, thoughts?

That paint scheme is very "BMERish". I kind of like the old BMW paint scheme. Any bike, any color as long as it is black with white pin stripes....

Tom

SOHC4 Cafe Racer Fan · « **Reply #16 on:** August 25, 2016, 04:45:33 PM »

The only thing is that the seat does not evoke vintage BMW.

Black seat, black paint, white pinstripe says BMW.

Example:

MrLonghorn · « **Reply #17 on:** September 06, 2016, 06:54:55 PM »

So, I took absolutely no pictures of the process, but with the following items I fixed the contour of the seat/hoop

A flexible cutting board (for template)
A sheet of ABS plastic.
A soldering gun.
A heat gun.
A flap disc.

Cut out template. Transfer template to abs sheet. Rough cut with angle grinder. Flap disc to grind to proper shape. Weld abs plastic to seat pan using soldering gun. Mix up acetone and and scrap to create ABS filler putty. Smooth out welded areas. Grind smooth. Fine tune shape to match hoop.

Final result.

MrLonghorn · « **Reply #18 on:** April 13, 2017, 05:36:35 AM »

It has been a long time since I updated this thread. My pops decided he really didn't want a motorbike, so this got put on the back burner for a bit.

Decided that I should finish it up and ride it for a while myself. Back to work I went:

Decided to run the tail/stop/turn LED inset into the rear hoop.

Still have some filler/cleanup work to do before paint.

Also decided to weld up a new oil tank/battery box.

Oil tank:

Battery box:

Getting closer to throwing some paint on things.

MrLonghorn · « **Reply #19 on:** April 14, 2017, 09:07:42 AM »

Working on some mini side covers. Still fine tuning the shape. Will probably drill some holes or open a large area and back it with mesh.

MrLonghorn · « **Reply #20 on:** April 17, 2017, 05:28:18 AM »

Refined the shape, welded up the mounts, made the matching left side, installed with temp hardware.

Also painted the oil tank and battery box and started making the new oil lines.

MrLonghorn · « **Reply #21 on:** April 20, 2017, 03:36:07 AM »

Wired up the tail light:

Threw some appliance epoxy on the tank, I don't think that there is a straight panel anywhere on this thing, HA:

Threw the sidecovers and the tank on the bike, rolled it out of the shop to get a good look. So far, I dig it.

SOHC4 Cafe Racer Fan · « **Reply #22 on:** April 20, 2017, 08:48:00 AM »

Looks pretty good. Just my opinion, but I'd (personally) eliminate the ridge between the knee dent and the rear of the tank, since it will rub on/cut into your knee and upper thigh when you grip the tank with your knees. That would bug the bejezus out of me.

News:

Author Topic: 1976 CB750F, for my pops. (Read 3606 times)