1980 GS550E + 2000 Katana 750

Not gonna lie.... took a big, long break from this project. Had life get in the way over the winter. Had lots of other distractions and, honestly, I just lost interest in it. I sold the Brat project with the stock 550 engine. I even tried to sell the 750 swap project and, I guess you could say luckily, I had no takers.

So... I took it apart and started working on it again.

I got the frame, swing arm and various bits and hangers painted yesterday. Today, I adjusted the valves (all were within specs but I snugged up the intakes just a bit) and slotted the timing advance plate to I can try advancing the timing once I get it running.

I tried to install the starter motor I bought a year ago only to find that I had a -'98 starter and I have a '00 motor. Doh! Got the correct one ordered and once it's installed I'll get the engine back in the frame and start putting this thing back together.
Got a roller. It's about time to start working on the wiring harness and electrics.




Not sure if anyone really cares or not, but I finally found some gumption to work on this thing again. Got the turn signals wired up today and ordered a battery. I have to find a frame ground for the GSX750F wiring harness. I think I can use the lower, front battery box bolt.

I got the Bandit 400 control wiring all figured out (I think) and I should be able to pop the battery in and see if any smoke gets out soon.

If it doesn't burst into flames, it won't be long until I add some gas and see if it starts!
Woo Hoo! Put a battery in it today and it turns over with the starter! The oil light went out after a few revolutions. I have tail light, brake light (both front and rear switches), horn and a hi beam indicator.

Most importantly, I have spark from both coils!

I *don't * have headlight or turn signals, so I'll have to trace that out. I don't think I have backlights on the Bandit 400 gauges, but I do see the tach needle "twitch" when I power it up.

I'll sort out those things and then add gas and see if she'll run!
Just checked and I DO have tach and speedo back lights. Just gotta figure out the headlight and turn signal situation.
So....checked out the diagram and the harness.

Checked out the fuses: all good. Checked and I have power where I'm supposed to have power. I was trying to run an LED headlight and turn signals. Tried the old headlight bulb and it works. When I test the LED bulb off the bike, it works.

Same with the turns. When I test them with a spare battery, they work. My engine/harness is from a '00 750. It uses the wired, multi-prong relay, https://www.ronayers.com/oemparts/p/suzuki/38610-03f00/relay-turnsignal .

I'm about to hit the search button to see what everybody is doing for LED lights on a 2000 Suzuki Katana, but will this work?


Even if I get the turns to work with a good/different relay, what is keeping the LED headlight from working? Are there better ways to get the turns to work?
OK.....found out that the prongs on the LED headlight bulb don't match the prong on the harness. I will work on depinning and repinning those when I have better light in the garage.

Found a 7 pin LED flasher relay for less than $14 shipped....have it on the way, too.

As soon as I get the wiring sorted and neaten it up a bit, I'll try firing her up!
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Swapped pins and got headlight to work. Yay!

Swapped polarity on all 4 turn signals and now they all light and blink (fast).
But they ALL blink. Left turn: all four.
Right turn: all four.

Could it be the indicator bulb in the dash, if it uses a single bulb? But the Katana and the Bandit (dash) both had a single bulb for the turns.
I'm not getting a turn signal indicator in the dash, either.
I had a similar problem when wiring my 360/378. I ended up having to put a diode in line on both of my turn signal + wires to keep the DC going in one direction rather than sneak it's way through to places it shouldn't go. Check out this comment that @teazer made in my build:
If you have a singe idiot light for both indicators, check this out http://pinkpossum.com/Lights.htm

It was a big help for me to get it all sorted out. That situation and yours aren't exactly the same issue that I had but they were enough related that they required being sorted out pretty much the same way. Good luck!
Today was fire up day!

At first, #1 was silly hot and #4 was cold-ish; and it was hard to get a nice idle. Some investigation found a diaphragm that wasn't seated properly on #4 and the intake manifold was crazy loose on #1. I guess I just forgot to tighten it up when I put it together. We fought it for a while, then just pulled the carbs and oil lines and tighten all of the manifolds while we were at it.

Seems to run pretty damn good now!

As a reminder: 2000 GSX750F engine, Yoshimura slip -on, BST-36 carbs with DynoJet kit, RamAir filters and a slotted timing advancer (stock, for now. I plan on going to a dyno soon).

Got some pics, then took it apart again. I pulled the tach signal wire loose installing the tank, so that had to come off. Then I noticed some gas weeping around the petcock screws. I need to see if they use fiber washers. I also need some rubber grommets for the side covers. The clutch could use some adjusting and I want some pin stripes on the tail cowl.
But, overall, I'm pretty happy with it.









I've only been up and down the street in front of my house so far. But I haven't crashed yet!
What do you guys think.... doesn't the tail cowl need a little matching pin striping?

Got th ed petcock rubber bits in. Hope to get it all back together this weekend.
Agreed on the tail striping. Aren't you glad it didn't sell? Great looking bike.
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