1978 GS750EC build in progress (lots of photos)

[christiank]

Hello. I've been meaning to start on thread in here for over a year. I'm actually trying to wrap up this project in the next few weeks or at least get it to a point where the bike can be regularly ridden while I continue to mess with it.

I bought nearly stock 1978 GS750EC from a fellow NYC Vin Moto member in NYC back in May 2011. The plan was for it to be an upgrade over my very clean CB500. I was looking for something a little bigger. The GS fit the bill but it was aesthetically a mess. The previous owner used it as a daily rider in NYC and it showed but it ran strong.

Great bike but looking a little shabby. Just about everything was covered in rust or flaking paint.














After purchasing it sat for a bit while I was riding and working on my CB500. It didn't get much attention because I was chasing an electrical short. I randomly would clean a few covers here and there, lube the cables, and replaced the rusty chain and rear sprocket.

[christiank]

Then it sat for a bit over a year while I wrenched on other projects before I decided I was going to tear it completely down and give it an overhaul. My plan was to try to minimize where I could as I went. While I have a concurrent CB350 project going these were the first two bikes I've ever torn into. Both are a continuous learning process.

The minimization started right away when I hack off any tab, bracket, or piece of metal off the frame that I didn't intend to use.







My friend had this Benji seat that was no longer being used so it made it's way to the GS. I eventually shortened the seat area by a good 6 inches or so.



Then the engine started to come apart and the paint stripper came out. Most of the paint was already flaking and gas from the carbs had eaten a lot off the top of the engine as well.

[christiank]

Some carb cleaning and rebuilding happened.





The two dots indicate carb 2. Was that factory or did a previous owner do that? What's the 70 indicate?



Bottom end cracked and good thing. The lower cam chain guide below the crank was cracked in half and the two screws were nearly unthreaded and bent.

[christiank]

I got tired of days and days of scrubbing and decided to try to repaint the engine with VHT engine paint. The color was "cast aluminum" I think. It came out pretty well. We'll see how it holds up. You can also see my CB350 engine in the background of a few shots. Those engine cases were glass bead blasted. Both finishes looking very similar even up close.

[christiank]

Next I started messing with the frame and some small fab work. Rear loop, shortened Benji seat, aborted foot control mock-up, gussets for the rear loop, electronics pan with trap door for the battery, new mounts for the stock foot controls, and a new home for the key switch.









Killed this idea for the brake pedal. It's just a mock-up that would have been heftier but it was overly complex. Plus it would have interfered with the kickstart.



Back to the stock foot pegs and brake pedal with new tabs to hang them on.

[christiank]

Now that the engine cases were clean and painted I moved on to reassemble this beast.

Transmission





Crank





Bottom end buttoned up



Cylinders painted



Top end just sitting in place

[christiank]

For the exhaust I wanted to run something shorter. I realized that if I had four outer headers I could route the exhaust underneath the frame and tuck the mufflers underneath. I found two outer headers on ebay and then we mocked it up. I also purchased two 2-into-1 exhaust fittings.

Mock-up





2-into-1 fittings welded onto the headers



Exhaust bracket tacked into place



Headers being painted with Fast Black exhaust paint. Headers had some serious rust that I took a grinder to and after a few coats of paint and the location they look decent on the bike.

[christiank]

Movement on the top end. New gaskets and shiny bolts.

[christiank]

Snugging up covers and seals and installing the clutch.

[christiank]

The frame, wheels, and a box of parts went to powder coat. A few things I painted myself.









Ahhhhhhhhhhhh!

[christiank]

And here's where I'm at as of last week. Jetting carbs, wiring her up, and tons of small tasks. The seat is off to a friend who is doing the upholstery. I'm excited about that.







More to come.

[GateKeeper]

WOW,,,,,what a nice transformation.....

You have some nice skills there....waiting to see the finished project...

Cheers

.

[allojohn]

Very impressive work, although the geometry on the rear brake linkage looks dodgy. Are you sure that's going to work?

[christiank]

Very impressive work, although the geometry on the rear brake linkage looks dodgy. Are you sure that's going to work?

That was just a mock-up made from cardboard and a bolt. It would have been heftier and I think it would have worked but it was overly complex. I aborted that idea anyway and welded on new tabs for the stock brake pedal.

[christiank]

WOW,,,,,what a nice transformation.....

You have some nice skills there....waiting to see the finished project...

Cheers

.

Thanks. I did this with friends and by reading every manual and website I could find. I did all of the metal and engine work but the actual welding was done by a friend.