Is this a common sound characteristic of a 750 ?

[pearljam724]

What could be happening is the exhaust collar is not correctly set , the collars turn on the exhaust pipe so they can be adjusted so there is a gap between the collar and the cylinder http://www.oldjapanesebikes.com/mraxl_G ... /sr73.html" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false; this is so the gasket between the pipe and the cylinder is slightly crushed sealing it up .

Aside of an improper adjustment of the collars. I'd bet anything that the gaskets are bad to begin with as this bike was poorly maintained and nearly every part on it is original and needs replaced. Are you saying, that the exhaust gaskets could very well be the cause of the " gluck " sound as well ? Or are you only referring to the leak ?

[Suzukidave]

That is likely the source of the goop running down your engine , as far as the sound its hard to grasp the the sound as a problem and the cause . And then you say its coming from the top of the engine ??

[Suzsmokeyallan]

It sounds like you have the surge issue and if you have not fitted the air corrector jets to the carbs, you should.
The surging is a lean condition caused by a slightly too large air corrector orifice that was originally fitted into the carb bellmouth.
The surging is mostly felt when on long hills with a slight decline and the bike in high gear running on compression during light coasting or a slight deceleration.
Applying a slight bit of rear brake and balancing some throttle usually makes it go away.
The fix by Suzuki was to fit a smaller sized air jet into the bellmouth in front of the factory pressed in one to reduce the ratio of air.

[pearljam724]

That is likely the source of the goop running down your engine , as far as the sound its hard to grasp the the sound as a problem and the cause . And then you say its coming from the top of the engine ??

Yeah, it sounds like it coming from the head. But, it's a little difficult to pinpoint exactly. Because, it only happens at slow engine braking and it's non existent at any other time. Including when it's idling. Which it idles perfect. I'm going to try my best to find the time to shoot a vid tomorrow of what I am referring to. But, we'll see how that goes. They are calling for bad weather here. Starting tomorrow.

[pearljam724]

It sounds like you have the surge issue and if you have not fitted the air corrector jets to the carbs, you should.
The surging is a lean condition caused by a slightly too large air corrector orifice that was originally fitted into the carb bellmouth.
The surging is mostly felt when on long hills with a slight decline and the bike in high gear running on compression during light coasting or a slight deceleration.
Applying a slight bit of rear brake and balancing some throttle usually makes it go away.
The fix by Suzuki was to fit a smaller sized air jet into the bellmouth in front of the factory pressed in one to reduce the ratio of air.

Thanks Allan. I'm aware of the air pilot issue. Causing surging, etc. I will consider the smaller jet. I don't feel my bike has a large surging issue. However, I live at the bottom of a large mountain range. I often take rides on the mountain and the only time I experience any type of surging is when the bike is coasting down a steep down grade, I'm in a high gear with no throttle applied. As you said. But, the " gluck " sound happens on a level, uphill, or downhill engine brake only at slower speeds. Where as the occasional surge happens as I described earlier. The once in a blue moon surge does not bother me, but if it's possible that the air jet is causing the " gluck " sound because the bike is running lean. Then yeah, I want to address that. My understanding from a read somewhere about it. Suzuki called for a #80 or #90 air jet replacement. Where can I find that jet ?

[Suzsmokeyallan]

Well if you can live with it I applaud you, but it bothers the heck out of me and I just had to fix it. You will notice besides the surging if you blip the throttle at the time its surging it hangs up around 1500 to 1800 for a brief moment before settling back down.
Its an easy fix and the jets are available from Sudco in 0.7 0.8 and 0.9, 0.8 is the recommended size.

[tz375]

It's a standard Mikuni VM type air jet. More details at http://pinkpossum.com/GT750/carb/BS40carbs.htm" onclick="window.open(this.href);return false;

[pearljam724]

Well if you can live with it I applaud you, but it bothers the heck out of me and I just had to fix it. You will notice besides the surging if you blip the throttle at the time its surging it hangs up around 1500 to 1800 for a brief moment before settling back down.
Its an easy fix and the jets are available from Sudco in 0.7 0.8 and 0.9, 0.8 is the recommended size.

I plan to strip the carbs over the winter, so I will do it for sure then. I've only ridden the bike for a couple hundred miles since owning it and one thing is also certain. I get major throttle hang up. I think 3 times and if I remember correctly. Each time was when I was coasting down hill. Throttle hung up around 7-8 grand for a few seconds, before settling down. Which I know that condition is caused from being lean. Just as you said.

[pearljam724]

It's a standard Mikuni VM type air jet. More details at http://pinkpossum.com/GT750/carb/BS40carbs.htm" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;

Thank you, all. I've been waiting for the fix to that server as well. You guys are pretty good. We'll see if that diminishes the " Gluck " sound. If weather's descent tomorrow, I'll post a vid tomorrow night. Thanks again