1977 550

[6ixshooter]

This is the picture I took of the cable not connected under the gas tank...

https://photos.app.goo.gl/FbMqePMZvCB9qhTZ8

[Rich82GS750TZ]

I’d be really concerned about he plug you put in vs the plug you took out. If the one you took out is the right one for your bike, that replacement looks way too long, like the piston would hit it. Just my opinion looking at the pics.

[6ixshooter]

The longer ones are supposed to match the ngk b8es. I was more concerned about the short ones I tookout.
I gained power after changing the plugs.
I went to two parts stores and had them look up the ngk, I bought 1 from one store and compared with the second. Both stores gave me the longer shank plugs so I figured they should be close to oem.

[roeme]

The new plugs are correct. It's no wonder you've had less power with the old ones, being that much shorter puts all kinds of things out of whack.

[Grimly]

The short ones are the kind of plug you would fit if you were in the middle of nowhere and had a box of lawnmower plugs in the shed, just to get it running.

[sam000lee]

Chiming in with others, the NGK B8ES is the correct plug. I live in Boston and depending on when I need them, sometimes end up having to go to 3-4 part stores to get a set of four. I'll typically just buy all the ones they have for spares. You should also be able to get them on z1. As for the oil filter, the correct K&N filter is the KN133. $8 or $9 on amazon and I'll also typically just buy a few at a time. Between me and my friends we have 6-8 GS's so it helps to have extras . Honestly at this point I just buy multiple of everything and then charge them when I inevitably end up replacing stuff.

The petcock has three positions:

ON: Lever pointing down. Vacuum operated.
RES: Lever pointing left. Vacuum operated.
PRI: Lever pointing right. NOT vacuum operated and pulls from the "reserve level" (i.e. bottom of the tank)

If your bike is only running in the Prime position then there's an issue with your vacuum line or the petcock itself. Check to make sure that there are two lines hooked up to the petcock. If only the fuel line is connected, the ON position wouldn't work and you'll also likely have a huge vacuum leak going into the carbs from the line that should be connected to the petcock (this could certainly cause/contribute to the symptoms you're seeing and also potentially cause engine damage).

As for the two throttle cables, your GS550 has a push and a pull cable. Your pull cable is the one that opens the carb slides so is almost certainly the one that is still connected. Just hook the other one back up. Better yet, pull the carbs and rebuild them and then hook everything up correctly.

For your benefit and to make it easier for us to help you, I'd recommend you create a flickr account so that you can post pictures inline.

I'm mostly done with my GS550 resto. I bought it for $900 and have spent about the same to get it to a point where it runs well, behaves well (suspension), and is safe (tires and brakes). I've brought back a few of these bikes at this point - it feels like a lot to spend up front but ends up being cheaper than doing things multiple times.

[6ixshooter]

Awsome info, I see only one line hooked up to the petcock..

https://photos.app.goo.gl/eg5PJFGYtgCdjsaBA

Also now aware of some lines that need changing.
This is the position I run best in, which correct me if I'm wrong but reserve?

https://photos.app.goo.gl/agEGEjeHvjc812MLA

Also I will make a Flickr account, I really dont do social media.
Carbs are already on my list. I'm planning on working on it this winter when work slows down and the snow is on the ground. Rn I'm trying to diagnose as much as I can and make a shopping list of parts.
I appreciate the help, I'm really learning alot about it

Right now I can ride pretty comfortable at 55 60, which is the speed limit here but I would rather not cause anymore damage. I might start my break down tomorrow.
I'll make the flicker account tonight so I can document everything.
I'm going to start at the exaust and carbs.

Thank you guys!

[Big T]

Nope, that picture shows your Petcock on Prime, not Reserve.
The lever points forward on Reserve

[6ixshooter]

Ok thanks, so possible I may need to replace? But most likely just the vaccum which could explain the bogging down on the throttle? I will clean up the petcock with the carbs in vinegar.
I was told this bike was sitting ina barn for 8 years, before that it was sold as scrap so hard telling what's been done to it.

[6ixshooter]

Sorry, my paper work shows it was bought as scrap and titled in 2016, so possibly 4 years sitting.
The guy I bought it from said he did nothing to it. He was going to fix it for his step son but the kid was scared of it.
The numbers on the title match both numbers on the bike so no worries there.
Lots of cosmetic work aswell but atm I'm more concerned with the important parts.
I thought it may have been bobbed, but it looks pretty stock for the most part, aside from being stripped down.
This may take a little longer than I'm planning but I'm really hoping to make it run smoothly and a little "prettier " by next summer.

[6ixshooter]

Also does this look like the right seat?

https://photos.app.goo.gl/ce8GGT2rxro3tFgt9

It came with the bike, which had a single seat tapped to it.
I threw it in my trunk and kinda forgot about it. I was going to throw it out but now I'm considering buffing it up and re cushioning and wrapping myself.

[6ixshooter]

Got some OEM replacement gaskets for the petcock for the #2 bike and flushed the vinegar in the tank and filled it up. The inside is spotless now which is really satisfying. I also bled the brake line which actually works great now, despite the original lines (swapping them out for both bikes soon anyway).

Installed Sonic Springs into both bikes.

For the #1 bike, we rebuilt the carbs with new O-Rings and it starts up and runs great.

I've been running errands on my #2 bike for the past 5 days and it runs fantastically, especially after putting in a new set of plugs. It's so quiet on the highway and I ended up pushing it up to 100mph. The bike took it no problem and had more to go so I'm quite please with that. My DRZ400 was stolen out of the driveway on Friday so with this up and running I still have the same number of rideable bikes...

I've been cleaning up little bits and pieces with an old toothbrush/rag/tin foil and it's cleaning up really nice as well. I desperately need to replace the tires on it so am ordering them in the next couple of days. I'm looking for a not-super-modern looking tire that won't sacrifice performance. On my other bikes I've used the Dunlop K70s (look cool), IRC GS-11's (also look cool) and Shinko 712's (cheap and perform decent), so hoping for something in between. Looking for suggestions if you have 'em.

Next up is replacing the brake lines.

That's pretty awsome. It looks so clean compared to mine lol. This is the one you restored?

[6ixshooter]

I did make a Flickr account, still cant Get my pictures to upload to the forum.
Currently I'm taking a smoke break after getting the carbs, airbox, battery box. Chain gaurd, foot pegs and foot break pedal out.
Those two middle carbs are scary looking...

https://photos.app.goo.gl/pH6sGHt5rTy6MqHp8

I'm not even sure how this thing was even running tbh.

Half the exhaust is out and I snapped off a manifold bolt... ugh. Probably gonna take the otherside out, clean all the parts and call it quits for today.

https://photos.app.goo.gl/11u7uaf2iT1ggxBFA

[cowboyup3371]

In Flickr, you'll click on the picture then click on the Arrow in the bottom right corner (sharing). Click on the BBCode tab and select the link then copy it to your clipboard. You can paste up to 10 pictures into a single post of any thread

Here's your first one uploaded to my Flickr account

20200927_104605 by Scott Baker, on Flickr

[6ixshooter]

In Flickr, you'll click on the picture then click on the Arrow in the bottom right corner (sharing). Click on the BBCode tab and select the link then copy it to your clipboard. You can paste up to 10 pictures into a single post of any thread

Here's your first one uploaded to my Flickr account

20200927_104605 by Scott Baker, on Flickr

Cool thank you.