Hi guys! This is my first motorcycle ever, I bought it in may 2013. A fairly stock 1977 model CB750 Four. I liked it but it was too much "late 70's" in my opinion. I'm trying to get it to look more like a rough and gritty "barn find" type, that could've been ridden by someone in a 1960's biker gang. That is, without transforming it into a chopper or a Cafe racer. I need the double seat to accommodate a female from time to time and long forks are not really my type. It should just look as "old" as possible. With the help from you guys I was able to make the first modifications and learn a bit about motorcycle maintenance as well. To say thank you I now want to show you how far I've come.
The bike when I bought it:
First I took of the side covers, removed the emblems and sanding it down to make the paint stick better to the surface. Then I added a coat of primer.
Same thing for the emblems...
...and the headlight case. Sanding off the chrome took a while.
Then I gave the side covers several coats of matte black, some a bit further away to get it dusted and some a bit closer to seal the dust. Some light sanding again and then a matte clear coat in the end. It gave a nice uneven finish, as if it were painted over rust, or paint deteriorating from standing 40 years in a barn. The emblems were painted gloss black and finished with a gloss clear coat.
The tires were ancient. The front tire was from 1987 (!) and the rear tire (pictured) was twenty years old, made in the 12th week of 1993. Riding around with those would have been life threatening so both had to be replaced. The front rim had a lot of rust build up on the inside that could only be removed with a rotating steel brush.
I found this nice fuel tank and some extras from an older model (74? Petcock was on the left just like the K7 tank) on an internet swap meet and upon getting them, began to prepare it all for the new paint job. First the fuel cap had to be removed, then it received the same treatment as the side covers.
Fuel cap back on and rubbers installed again.
There was a bit of surface rust on the inside, but nothing that couldn't be removed with some gallons of vinegar.
The vinegar is slowly dissolving the rust. Then it was time to remove it and flush the inside with water and immediately spraying it with a lot of WD-40 oil to seal it.
Off with the old fuel tank...
...and using a Dremel to cut the new steel braided fuel hose.
Installing the hose...
...and on comes the tank again. The fitting hasn't changed since the first model so this was fairly easy. You just need and older style tank rubber.
There was just one problem: The older style tanks are almost 5 cm shorter then the '77 models. What to do?
I found some foam rubber in the attic...
...and used my sushi knife to cut it.
It was the only thing sharp enough for the job.
But I didn't want the seat it to be longer than the original so I opted for shifting the attachment points about 4 cm further.
As the seat was an aftermarked part made of epoxy-glass resin or glass fiber this was easy and a regular drill insert on the dremel could be used as a milling cutter.
Seat lock back in place.
One of the holes was still used so it only needed one more attachment point for each of the hinges...
...that also made sure that the correct distance was maintained. All hinges are now attached again.
https://lh5.googleusercontent.com/-zBLo50T_IIo/UjNw3RlMMjI/AAAAAAAAC5s/dsmtK2H7UvE/s800/24.jpgThen it was time to change the seat cover. I didn't like too much black so I opted for a vintage brown one.
The dark brown rubber piping was quite easy to sew on to the newly cut centerpiece.
Finished seat and seat cover.
The strap in the middle must have some reinforcement in order not to rip or stretch so i used some PALS webbing I had lying around. Don't ask.
Then the seat cover was ready to be permanently attached again using a rivet gun. Now the seat is finished.
On to the rear light. When I bought the tank I also got a bunch of other parts from that guy including the older rear light holder. First the top was cut off as the new rear light was to be mounted horizontally instead of vertically (notice the concave shape at the top) and then the old paint and rust was removed with this rotating steel brush.
On the other side a little metal part was welded in, with the attachment points for the new rear light.
Then it was time to weld the little metal parts that were holding the indicators to some threaded pipes I got off ebay. The indicators and rear light are from a retro Triumph Bonneville T100.
https://lh5.googleusercontent.com/-lV2v7rGUDX0/UjNw7in7GvI/AAAAAAAAC64/YS-pa1XNUbU/s800/32.jpgAll welded on and ready to be assembled.
The rear light holder was painted silver...
...and the indicator cases matte black. I was cutting off around 2cm from the indicators cases that are going to be in the rear.
The rear light attached to the holder and the wiring routed.
Last picture of the old rear light and indicators before the new stuff went on.
...and here's the new ones already attached. Much less 70's now.
Also the front indicators had to go.
But the old metal tubes were really difficult to remove so I had to use brute force to get it off...
and here's why: Decades of rust and debris built up on the threading. I'm not sure if these things were original. After the rust was removed the theaded portion was cut and also a slot was grinded in at the end so now it could still be used as a screw to hold the fork ears in place. Now it's finished.
The air filter box was bleached out from UV light over the years and the attachment to the carburetors was poorly due to the missing pipe clamps so it was time to do something about this as well.
The box was taken off and the attachment points cleaned.
The major scratches on the box were sanded off...
...and received two coats of this black waxy stuff to restore the color again. Then some pipe clamps were attached to the tubes, as the bike had none installed before. (I removed those generic pipe clamps again recently and installed the original ones from Honda. They original ones were narrower and the generic wider ones were almost pulling them off, possibly leaving some space for air to come in)
Air filter back in and attached to the carburetors. That was pretty much everything so far.
And now it looks like this...
...much better...
...and much more classic.
From the rear...
...and from the side. Some other small changes included flipping the mirrors upside down and adding some 60's style handlebar grips, replacing the clutch cable and and adding a xenon kit to actually see something at night. My plans are for the winter to get the complete K0-K6 fork setup also painted in the same style.
