• Required reading for all forum users!!!

    Welcome!
    Register to access the full functionality of the GSResources forum. Until you register and activate your account you will not have full forum access, nor will you be able to post or reply to messages.

    A note to new registrants...
    All new forum registrations must be activated via email before you have full access to the forum.

    A Special Note about Email accounts!
    DO NOT SIGN UP USING hotmail, outlook, gmx, sbcglobal, att, bellsouth or email.com. They delete our forum signup emails.

    A note to old forum members...
    I receive numerous requests from people who can no longer log in because their accounts were deleted. As mentioned in the forum FAQ, user accounts are deleted if you haven't logged in for the past 6 months. If you can't log in, then create a new forum account. If you don't get an error message, then check your email account for an activation message. If you get a message stating that the email address is already in use, then your account still exists so follow the instructions in the forum FAQ for resetting your password.

    Have you forgotten your password or have a new email address? Then read the forum FAQ for details on how to reset it.

    Any email requests for "can't log in anymore" problems or "lost my password" problems will be deleted. Read the forum FAQ and follow the instructions there - that's what we have one for...

  • Returning Visitors

    If you are a returning visitor who never received your confirmation email, then odds are your email provider is blockinig emails from our server. The only thing that can be done to get around this is you will have to try creating another forum account using an email address from another domain.

    If you are a returning visitor to the forum and can't log in using your old forum name and password but used to be able to then chances are your account is deleted. Purges of the databases are done regularly. You will have to create a new forum account and you should be all set.

Breezy Airbox

  • Thread starter Thread starter MisterCinders
  • Start date Start date
M

MisterCinders

Guest
I see the recommendations to seal up, weatherstrip, etc. the airbox.

When I changed my air filter this weekend (1978 GS750), the side covers seemed pretty tight. Once the old filter was out, I could see that there is a large opening in the rear of the box. It's about 3 inches, but looks deliberate. Not a crack or missing chunk, but a specifically cut notch. I'll try to remember to snap a pic later.

Is this right? Is there a piece missing? Seems odd to have a big opening there, given everyone's emphatic calls to seal that box up.
 
There is supposed to be a rubber snorkel there, it is more like an intake muffler I think.
The carbs are calibrated to run correctly with it in place, might be too lean without it.
 
Today 01:41 PM tkent02 There is supposed to be a rubber snorkel there, it is more like an intake muffler I think. The carbs are calibrated to run correctly with it in place, might be too lean without it.

+ 1, it is likely too lean and usually will also have a big flat spot between 3 - 5 K when you roll the throttle hard. E-bay for a used airbox with one still in it is probably the easiest place to fine one.
 
Hmm, where might I find one of these parts? Came up short at Z1.
 
You have a 1978 with VM carbs, they are not so sensitive to intake restrictions and they are easier to tune than the later CVs. It's probably easier to rejet the carbs than find that snorkel. If you have this flat spot, try going up to the next bigger main jet, then do plug chops to see if you got it right.

Z1 sell the jets, I believe your bike comes with 102.5 stock, so 105 would be the next larger jet.

You never did mention how well it runs now.
 
I think the snorkel will look like this.:)

100_4995.jpg


100_4999.jpg
 
Wierd. So the back of the box is supposed to be open? Or did someone swap the box on this bike? The diagram does not show the back of the airbox where the notch is. Could it be a solid piece on that year?
 
Also, what is the difference between the 1978 GS750C and 1978 GS750EC?
 
You have a 1978 with VM carbs, they are not so sensitive to intake restrictions and they are easier to tune than the later CVs. It's probably easier to rejet the carbs than find that snorkel. If you have this flat spot, try going up to the next bigger main jet, then do plug chops to see if you got it right.

Z1 sell the jets, I believe your bike comes with 102.5 stock, so 105 would be the next larger jet.

You never did mention how well it runs now.

It runs a bit rough, but I need to do valves, carbs, etc. Hitting that next.
 
Also, what is the difference between the 1978 GS750C and 1978 GS750EC?
C had a single front disc and wire wheels. EC had dual front discs and mag wheels. Other minor differences, but those are the two biggies.
 
Both the airboxes my friend got had that hole, I think he also has single disc and mags.
 
According to the fiche there is no snorkel...

http://www.alpha-sports.com/suzuki_parts.htm?fpg=/spst/1978 GS750E/01.htm

My friend got a '78 750 and it came with 2 airboxes... no snokels. Ive also looked on ebay and found nothing.

Whatchoo talkin 'bout, Willis? :confused:

In that diagram, you can see the upper edge of the snorkel peeking out from the back of the airbox, beneath parts 11, 12, and 13.

The snorkel is not available as a separate part, but it appears this motorcycle did have one from the factory.

And yes, it is tragically common to find that misguided POs have removed the snorkels, thinking it'll somehow improve performance. It does not. Quite the opposite, in fact.

As noted above, it might be easier to rejet than to find a good snorkel. They are depressingly rare, although a plea in the parts wanted section may get results.
 
Whatchoo talkin 'bout, Willis? :confused:

In that diagram, you can see the upper edge of the snorkel peeking out from the back of the airbox, beneath parts 11, 12, and 13.

The snorkel is not available as a separate part, but it appears this motorcycle did have one from the factory.

And yes, it is tragically common to find that misguided POs have removed the snorkels, thinking it'll somehow improve performance. It does not. Quite the opposite, in fact.

As noted above, it might be easier to rejet than to find a good snorkel. They are depressingly rare, although a plea in the parts wanted section may get results.

ooooh THAT snorkel!
Really though? Thought that was just an edge of the airbox... looks like I'll have to tell my friend to add that to the list of things to get...
 
Does your airbox look like this on the back?

http://cgi.ebay.com/ebaymotors/79-S...3299963QQptZMotorcyclesQ5fPartsQ5fAccessories

If so there was a snorkel on there at one point, it is part of the airbox assembly and does not show up on parts fiches as a seperate number. I am pretty sure most snorkels were the same size though, Suzuki usually did not re-invent the wheel for parts like this. When I got one of my bikes it was missing and as Tkent mentioned the CV carbs are VERY touchy on intake air mix. I ended up taking a chance getting an earlier 850G type box for an L model and the snorkel fit perfectly. Maybe measure your airbox and expand your options on finding one. I can check the dimensions on the L type box. If they are the same that would expand your options to include G & L type boxes. Most of the boxes on e-bay are missing the snorkel if they even give you a picture of both sides. :o Unfortunately they are usually not cheap either.

The missing snorkels are out there somewhere with all the missing PO titles. :eek:
 
LAFFO!

My bike has single front disc brake and mag wheels.

:confused:
Your bike is also 32 years old. Anything could have happened. In your case, it sounds like a PO purchased mag wheels and moved the single disc from the spoke wheel to the mag wheel. That way he did not have to change a lower fork leg for the second disc or run the second line. Just a thought.
 
Does your airbox look like this on the back?

http://cgi.ebay.com/ebaymotors/79-S...3299963QQptZMotorcyclesQ5fPartsQ5fAccessories

If so there was a snorkel on there at one point, it is part of the airbox assembly and does not show up on parts fiches as a seperate number. I am pretty sure most snorkels were the same size though, Suzuki usually did not re-invent the wheel for parts like this. When I got one of my bikes it was missing and as Tkent mentioned the CV carbs are VERY touchy on intake air mix. I ended up taking a chance getting an earlier 850G type box for an L model and the snorkel fit perfectly. Maybe measure your airbox and expand your options on finding one. I can check the dimensions on the L type box. If they are the same that would expand your options to include G & L type boxes. Most of the boxes on e-bay are missing the snorkel if they even give you a picture of both sides. :o Unfortunately they are usually not cheap either.

The missing snorkels are out there somewhere with all the missing PO titles. :eek:


Yep, that's definitely a snorkel slot.





The word "snorkel" sure is fun, huh?

Snorkel snorkel snorkel snorkel snorkel snorkel!


Snorkel!

(Snorkel.)
 
The word "snorkel" sure is fun, huh?

More useless fun info from the internet:

The word "snorkel" comes from the German word "schnoerkel", which was a tube used by German submarine crews in WW2. The subs used an electric battery when traveling underwater, which had to be recharged using diesel engines, which needed air to run. To avoid the hazard of surfacing to run the engines, the Germans used the schnoerkel to feed air from the surface into the engines.
 
More useless fun info from the internet:

The word "snorkel" comes from the German word "schnoerkel", which was a tube used by German submarine crews in WW2. The subs used an electric battery when traveling underwater, which had to be recharged using diesel engines, which needed air to run. To avoid the hazard of surfacing to run the engines, the Germans used the schnoerkel to feed air from the surface into the engines.

OK, but did they forget about the exhaust bubbles rising to the surface?

Wouldn't that give away their location, as well. Like a fart in a bath tub ? :p
 
Back
Top