78' GS750 Carburator Hose question

[Guest]

Hi Folks,

I'm getting close to starting up a garage sale purchase 1978 GS750E and wanted to know where the vacuum from the petcock connects with the carb system.

Here are two pictures of my carbs and I put a blue cap on the port I believe is the vacuum port. Also, why are two ports plugged on the right
side?

https://kenmurray.smugmug.com/1978-Suzuki-GS750/i-kLxWtQG/A

https://kenmurray.smugmug.com/1978-Suzuki-GS750/i-PP3JPBB/A


Thanks,
Shred

 

[allojohn]

Nope, #3 is the vacuum port, hoses on 2 & 4 should vent to calm air over the airbox.
3 & 4 ports are blocked because someone didn't know what they were doing.

 

[Rich82GS750TZ]

This very well could be the most common question asked on the forum, it certainly is very common, especially when someone gets a GS that doesn't run or runs poorly. It sure would be nice if someone would fix the pics in this link, or create a new article with clear picture of where the hoses go on Both VM and CV carvb. I know I've seen both, so they do exist. I'm just not able to locate them. Not planning to take my carbs off any time soon, or I would do it myself for the CVs. The other broblem is getting files placed on BikeCliff's, which, for whatever reason, seems difficult. Not a Criticism of Bikecliff's site nor the fine folks who have made it the great resource that it is. Lord knows, it's become my favorite website next to this one.

http://members.dslextreme.com/users/storagecliff/images/hose_locations.html

 

[Guest]

Nope, #3 is the vacuum port, hoses on 2 & 4 should vent to calm air over the airbox.
3 & 4 ports are blocked because someone didn't know what they were doing.

Thank you John!!!

 

[Guest]

Nope, #3 is the vacuum port, hoses on 2 & 4 should vent to calm air over the airbox.
3 & 4 ports are blocked because someone didn't know what they were doing.

He drilled (6) 5/8" holes thru the bottom of the air box that I sealed up. I don't know anything about carb settings but I have a feeling these won't be dialed in exactly

 

[allojohn]

Start with the fuel screw (under the carb) at 7/8th of a full turn out and the air jet at 1.5 out. Adjust the airs screws using the highest idle method. Once you have that done you'll need a manometer to balance the carbs.

But all of this may be in vain if you haven't adjusted the valves or cleaned the carbs yet. The 24hr carb dip method is non-negotiable, and while you're there you find out what size pilot/main jets you have.

 

[Guest]

Start with the fuel screw (under the carb) at 7/8th of a full turn out and the air jet at 1.5 out. Adjust the airs screws using the highest idle method. Once you have that done you'll need a manometer to balance the carbs.

But all of this may be in vain if you haven't adjusted the valves or cleaned the carbs yet. The 24hr carb dip method is non-negotiable, and while you're there you find out what size pilot/main jets you have.

Thanks John!!

 

[Guest]

Start with the fuel screw (under the carb) at 7/8th of a full turn out and the air jet at 1.5 out. Adjust the airs screws using the highest idle method. Once you have that done you'll need a manometer to balance the carbs.

But all of this may be in vain if you haven't adjusted the valves or cleaned the carbs yet. The 24hr carb dip method is non-negotiable, and while you're there you find out what size pilot/main jets you have.

Hey John,

I'm going to take the carbs off today and soak them for a couple of days in white vinegar. I have 4 into one exhaust but I found some pristine stock pipes in Winnipeg that should be here by next Friday. What jets will I need for the stock pipes?

Thank you!

 

[allojohn]

Hey John,

I'm going to take the carbs off today and soak them for a couple of days in white vinegar. I have 4 into one exhaust but I found some pristine stock pipes in Winnipeg that should be here by next Friday. What jets will I need for the stock pipes?

Thank you!

White vinegar likely won't be powerful enough, get a gallon can of carb dip (24 hrs) - Berrymans, Napa or whatever...
Stock pipes and stock air box - 102.5 main jet, 15 bleeder (pilot) jet will work fine.
Switching from/to 4-1 and the stock pipes doesn't make a much of a difference that I can tell - I change every so often and never mess with the jetting.

 

[Big T]

http://members.dslextreme.com/users/bikecliff/images/vm_carb_rebuild.pdf

Order your O rings and follow this tutorial

 

[Guest]

White vinegar likely won't be powerful enough, get a gallon can of carb dip (24 hrs) - Berrymans, Napa or whatever...
Stock pipes and stock air box - 102.5 main jet, 15 bleeder (pilot) jet will work fine.
Switching from/to 4-1 and the stock pipes doesn't make a much of a difference that I can tell - I change every so often and never mess with the jetting.

Thank you John!

 

[Guest]

http://members.dslextreme.com/users/bikecliff/images/vm_carb_rebuild.pdf

Order your O rings and follow this tutorial

Thank you Big T! I don't feel confident enough to do a full rebuild. I barely know what I'm doing.

 

[Guest]

http://members.dslextreme.com/users/bikecliff/images/vm_carb_rebuild.pdf

Order your O rings and follow this tutorial

I just looked over that PDF. Sweet! d.o.w.n.l.o.a.d.i.n.g

 

[chuck hahn]

Berrymans for 24 hours. take the basket out and you can put 2 bodies in the can at once. use bread tie wire and wire the jets to one of the bowl screws hole.

 

[Big T]

Thank you Big T! I don't feel confident enough to do a full rebuild. I barely know what I'm doing.

Barely know what you're doing, but willing to bang your head against the wall instead?

The GSR exists to pass our accumulated mistakes on to you, so that you can do things the right way

Go here -https://www.thegsresources.com/_forum/showthread.php?196338-New-Members-CLICK-HERE!! (it's the sticky in the GS Owners forum)

Read thru everything -especially the Top 10 Newbie Mistakes (made just for you!) and the BassCliff website. Get yourself a factory service manual there and check out the valve adjustment, carb sync and electrical tutorials. Yes, some of links are broken

Ready? Get yourself an egg carton, a can of carb dip, a JIS screwdriver, small metric sockets, an impact driver and order up a set of O rings for the carbs and intake boots.

Aaaand, Go!

 

[Rich82GS750TZ]

........................

 

[Guest]

Barely know what you're doing, but willing to bang your head against the wall instead?

The GSR exists to pass our accumulated mistakes on to you, so that you can do things the right way

Go here -https://www.thegsresources.com/_forum/showthread.php?196338-New-Members-CLICK-HERE!! (it's the sticky in the GS Owners forum)

Read thru everything -especially the Top 10 Newbie Mistakes (made just for you!) and the BassCliff website. Get yourself a factory service manual there and check out the valve adjustment, carb sync and electrical tutorials. Yes, some of links are broken

Ready? Get yourself an egg carton, a can of carb dip, a JIS screwdriver, small metric sockets, an impact driver and order up a set of O rings for the carbs and intake boots.

Aaaand, Go!

You sure know how to burst a bubble Big T :biggrin::biggrin: can't I just soak the carbs in vinegar and shake everything out the drain hole? I don't want to start stripping out tiny screws. I'd be screwed then for sure. There was no lacquer or sediment in the bottom of the gas tank only rust inside. I'm going to hope the carbs will be fine and that he drained the gas tank before storage. I need to successfully complete more work on this bike before becoming carb man.

The world is a complicated place. I did read the new member info and went over to the Basscliff and Resources area but it like drinking from a fire hose. I'm just finding my legs with this bike stuff. I use to work on my own cars as a kid through about emission central and sensored up car upgrades. Then I let the pro's do it. I will get one of those egg carton hats though

I do have the bike service manual but it doesn't cover what experience is needed.

 

[Rich82GS750TZ]

I'm going to hope the carbs will be fine and that he drained the gas tank before storage.

I’m going to paraphrase Steve: you can do it right, or you can do it over.

 

[Big T]

You sure know how to burst a bubble Big T :biggrin::biggrin: can't I just soak the carbs in vinegar and shake everything out the drain hole? I don't want to start stripping out tiny screws. I'd be screwed then for sure. There was no lacquer or sediment in the bottom of the gas tank only rust inside. I'm going to hope the carbs will be fine and that he drained the gas tank before storage. I need to successfully complete more work on this bike before becoming carb man.

The world is a complicated place. I did read the new member info and went over to the Basscliff and Resources area but it like drinking from a fire hose. I'm just finding my legs with this bike stuff. I use to work on my own cars as a kid through about emission central and sensored up car upgrades. Then I let the pro's do it. I will get one of those egg carton hats though

I do have the bike service manual but it doesn't cover what experience is needed.

You need to understand that buying an old bike has not only a learning curve, but a fi nancial burden
Expect to spend somewhere from $500-1,000 to make your bike roadworthy.

If you worked on cars before, it's really not much of a leap to bike carbs, there's just 4 of them

Plus, you get to buy more tools
What could be better than new tools and new skills?

JIS screwdrivers from gofastinnovations.com
O rings from cycleorings.com
Small metric sockets from Harbor Freight
Valve shim tool from Motion Pro
Steve's valve spread sheet
Valve cover gasket

And you're 90 per cent of the way there!

 

[Guest]

You need to understand that buying an old bike has not only a learning curve, but a fi nancial burden
Expect to spend somewhere from $500-1,000 to make your bike roadworthy.

If you worked on cars before, it's really not much of a leap to bike carbs, there's just 4 of them

Plus, you get to buy more tools
What could be better than new tools and new skills?

JIS screwdrivers from gofastinnovations.com
O rings from cycleorings.com
Small metric sockets from Harbor Freight
Valve shim tool from Motion Pro
Steve's valve spread sheet
Valve cover gasket

And you're 90 per cent of the way there!

Lol, I've been totally jazzed about the tool purchases. I mean, who doesn't love an impact driver, hammer and chisel with a stubborn Phillips screw. Homie wins that battle every time I'm sooo metric now I have a European accent when I burp, and a rack of flat head and Phillips screw drivers for only $9.95 that takes up half the work bench Who needs that many screw drivers. Back in the day you had 2 favorites that did everything.

But seriously, I'm having the time of my life right now with this bike. I bought it with the first stimulus check because I love bikes and I miss the 70's like you read about. They were the best years of my life. I have severe emphysema and at one point in the last 4 years I was completely couch ridden 24/7. Now I scoot around the bike with my stool and half inch drive socket set like I'm working on a ship in a bottle with a couple of ax handles.

I just got the sweetest set of stock pipes from ebay UK shipping from Winnipeg, MB. They are damn close to new looking. The wife got dropped from unemployment here in FL because she refuses to go back to work at this time so I'll have to cut back on my restoration a bit but life really doesn't get better than this and I'm truly grateful for the support I'm getting here.

I'm going to get a black light and some black light posters for the carport and a Lava lamp and just dig it. Thanks for your help Big T!! Be well brother!!