Strange discovery adjusting valves

[NCGS]

I took the tank off of my ‘81 GS750 to do a valve adjustment this evening and saw something odd. This is still a new bike for me so I’m still discovering all its hidden secrets. This is the first time I’m adjusting the valves on this bike.

Upon removing the tank I noticed a metal tab on one of the coil mounting bolts that had a jagged edge on it. The throttle cable has clearly been rubbing it and has worn through the sheath. So, I need a new cable. But what is this tab supposed to be? Was it meant to be a clamp or guide for the throttle cable? Maybe it just broke off? I removed it but I’m curious what it’s function was.

Also while removing the tank I found a half moon shaped rubber piece that fell on the shop floor. It looks like it must be meant to cover the frame tube and be a pad that the tank rests on. But is there supposed to be more than one?

I also found the outer cover on one of the ignition coil wires seems to have separated from the coil a bit. I don’t think it’s a problem but wanted to solicit opinions on that.

Thanks.

 

[NCGS]

Sorry apparently you can only have one picture per post. Here’s the half moon rubber piece.

 

[NCGS]

And here’s the coil wire.

 

[uk gs nut]

The tag that has rubbed the throttle cable should be longer and have a plastic coating. The rubber half moon looks aftermarket, are all original mount rubbers present?. The coil lead is the outer sheath and if the lead under it is sound I wouldn't worry about it. Maybe the tank was rattling and previous owner added that rubber ring.

 

[NCGS]

Thank you. So is that tag supposed to be a guide for the throttle cable to slide back and forth in? It seems like it might not be necessary.

 

[uk gs nut]

Yes just a guide, one of my bikes has it missing. I used a zip tie loosely fitted.

 

[Supercub]

The half moon rubber fell out of the head at the end of the cam when you pulled the valve cover. You will see the other three at the cam ends. They seal the blank space when put the cover back on.

 

[Rich82GS750TZ]

The half moon rubber fell out of the head at the end of the cam when you pulled the valve cover. You will see the other three at the cam ends. They seal the blank space when put the cover back on.

No, That's not the half-moon to which the OP is referring. The valve cover has not been removed. C-Shaped would be a better descriptor than half-moon. See pic in post # 2. It's a rubber pad that protects the tank from hitting the frame. Not sure if OEM or not. My bike doesn't have them. Recommend the OP check a parts fiche on a site like partshark.com. I can't claim to have ever seen those before.

 

[Supercub]

Ok well it cant be that.

 

[rphillips]

Yep, fuel tank cushion, found on fische for GS750 and 1100 EX

 

[Rich82GS750TZ]

Rphillips, curious which fiche page/sub-assembly you found the cushion.

 

[NCGS]

Right, I have the half moon pieces that go in the cylinder head. C-shaped is a better description. In any case, it’s clearly not a critical part.

 

[rphillips]

On the fiche page for the 750 and 1100 "EX" ( not on the ET) "fuel tank", not on the frame fiche

 

[Rich82GS750TZ]

Ah, there it it. Fiche shows only one, and only on the '81 (x) Model. Anyway, Mystery solved.

 

[NCGS]

So where is it supposed to go? Up near the steering head or down towards the seat?

 

[Rich82GS750TZ]

I would say, put it where it seems to do the most good. The tank is bolted to frame at the back, and captured at the front by the rubber hockey puck shaped cushions. The piece in question has to go somewhere in the middle.

 

[Grimly]

Iirc, there's one on each horizontal tube so the tank can't wobble and contact the frame, causing a rattle and even worse, wearing a hole in itself.

 

[NCGS]

Good grief. Did I screw this throttle cable up or is it supposed to be like this?

 

[Runningdog]

Don't worry about the loosish cable elbow. Aftermarket parts sometimes fit slightly differently, but work just fine.

The two hole throttle tube is typical for the older GS750s with the VM carbs, which have two cables. You've installed correctly, from what is visible.