78 1000 carb specs

[Guest]

i found this chart on basscliff's site but it doesn't cover 78. anyone know where 78 GS1000EC info can be found, or if any of the below is relevant?

[Steve]

I think the '78 was the same as '79, but won't guarantee it.

The '77 was just a bit different with the way the needle mounted and possibly different jetting.

.

[7981GS]

For one, I believe that at least the main jets were 97.5's. IIRC
Later years had increasingly tighter emissions.

Eric

[chuck hahn]

Theres a service manual at his bikecliff website.

[BassCliff]

Hi,

Not sure how much this will help but here's an entry from the carb spec sticky:

http://www.thegsresources.com/_forum/showpost.php?p=673066&postcount=82

This section of Mr. first timer's post may be most applicable, but I think this is for a modified intake/exhaust:

sudco recomends for the GS750/GS1000 (A12)
#115 mains
.9 air jet
#25 pilot jet
5dl31-3 needle
0.6 needle jet
2.0 throttle valve (cut away)

This manual (GS1000C/E/S/L Service Manual (67MB)) ("C" being the '78 model year) has these specs for the stock VM26SS carbs:

Pilot Air Jet: 1.2
Pilot Jet : #15
Cut-a-Way: 1.5
Jet Needle: 5DL36-3
Needle Jet: O-2
Main Air Jet: 1.5
Main Jet: #95
Float Height: 23-25mm
Fuel Level: 3-5mm

And that's about all the research I have for you.

Thank you for your indulgence,

BassCliff

[Agemax]

the 78 EC had 95 mains standard

[sedelen]

Service Manual here, you'll find what you're looking for in the lower of page 2-5 and the upper part of page 2-6. Takes a little time to download.

http://www.mtsac.edu/~cliff/storage/gs/GS1000_C-E-S-L_Manual.pdf

[Big T]

The 78s are the same-95 main,15 pilot

[shwaz]

i can't find the numbers on a bunch of the parts, but i can see for sure that the jet needle is 5DL36-3, which is the bone stock setup.

this bike, however, has a kerker 4-1 and pods. (i haven't had it running, just got it). does this mean that work was neglected, or could it run fine with pods and 4-1 with that same needle?

[Nessism]

With VM carbs you can often use the stock needle after you raise it some amount (not sure how much).

[shwaz]

With VM carbs you can often use the stock needle after you raise it some amount (not sure how much).

does "raise it some amount" mean changing which clip it's using? cause this one is still in position 3, same as stock.

[Big T]

does "raise it some amount" mean changing which clip it's using? cause this one is still in position 3, same as stock.

Correct

Placing the clip closer to the needle tip raises the needle, allowing more fuel in

You may need a magnifying glass to see the numbers

[shwaz]

Hi,


This manual (GS1000C/E/S/L Service Manual (67MB)) ("C" being the '78 model year) has these specs for the stock VM26SS carbs:

Pilot Air Jet: 1.2
Pilot Jet : #15
Cut-a-Way: 1.5
Jet Needle: 5DL36-3
Needle Jet: O-2
Main Air Jet: 1.5
Main Jet: #95
Float Height: 23-25mm
Fuel Level: 3-5mm

And that's about all the research I have for you.

Thank you for your indulgence,

BassCliff

With VM carbs you can often use the stock needle after you raise it some amount (not sure how much).

this bike does have the stock needle, and in the stock clip position. does that make sense for a bike that has 4-1 and pods?




i'm fairly certain this is the pilot jet, but it clearly says 17.5 on it. that's confusing given the manual says the stock is #15. is this just #17.5 or am i missing something




please correct me if i'm wrong here. i think this is the main air jet

it looks like it says 125, which i'm guessing is 1.25, which is smaller than stock. does that make sense for a bike with a 4-1 and pods?





thanks for all the help. trying to take stock of what i bought here and figure out what i should replace while it's apart, rather than possibly putting it back together with the wrong stuff

[OldVet66]

You need to get the stock 15 pilot jet back in there. It doesn't change with 4-1 pipes and pods. A Dynojet stage three jet kit makes it a lot easier to dial in, and has a better taper on the needles for the application. You will also want to remove the vent hoses on either side of the petcock vacuum port.

[shwaz]

You need to get the stock 15 pilot jet back in there. It doesn't change with 4-1 pipes and pods. A Dynojet stage three jet kit makes it a lot easier to dial in, and has a better taper on the needles for the application. You will also want to remove the vent hoses on either side of the petcock vacuum port.

managed to pull a set of 15s out of an incomplete spare set of carbs, so i should be ok for the pilot jet.

I'm not clear what all you get with the Dynojet. I understand that the needles have a different taper than stock; other than that it looks like they give you a choice of two main jet sizes but I can't even see what sizes they are to make an informed decision. at $100 that sounds pretty pricey.