Pods, Pipes, Panic! (Help! Your Bike has Pods)

[blowerbike]

so you have adjustable needles for sure?

[Brad sweet]

i need to pull one and check..

[duaneage]

Do high speed plug chops and read them. No one can tell you what to do from riding descriptions.

[Ric]

Referencing this link:

http://members.dslextreme.com/users/bikecliff/images/carbspec_float_height.html

Your bike came with 112.5 mains and 42.5 pilots.

According to this link:

http://motorcycles.wikia.com/wiki/Rejetting

You need 127.5 main jets and 47.5 pilots.

Raise your needles about a mm, as per the WAG method(WAG - wild-@$$ guess).

[boris.h]

Hi everybody
Sorry for diusturbing everyone, with my "case"...
I have a GS 550 E 1979, with VM22SS carbs, 4/1 with smg like a free megaphone exhaust, and a grid into the airbox....
Historically, I puted 110 mains and had a "lean" behaviour... I did yesterday plug chops at WOT and half throttle (to see about the needle position), my spark plugs were very.... white. I tested 120 mains, but I could not go up 3000 rpm.... I am putting 115 mains now, with the clip on the 3rd position. I will try it tonight or tomorrow. I am so surprised that, with a free 4/1 exhaust, and a grid into the airbox, that I have to increase the size of mains about 40 / 45%!!! I think a grid into the airbox is a good solution to increase performance.

http://imagesia.com/20150323-225342_vxi0

[wally]

I bought a pair of Uni double foam filters and a 6-Sigma jet kit. They supplied two sizes of main jets, pilot jets, a couple of drill bits in case I wanted to do wilder mods (which the instructions warn repeatedly can cause low speed/throttle drivability problems and should only be performed for racing purposes), and several shims for the fuel needles, as well as a pretty good set of instructions. The kit was reasonably priced ($56 shipped for a two carb kit) and they sent me an email asking about any mods and normal riding elevation.

SoHum, let me know how the jets work. Contemplating a set, but with our really crappy exchange rate it is a bit pricey!

thanx!

[Big T]

Guys, this is an informational stickie

You should read it and post up your problems in the forum below, not here

[boris.h]

Ok so I'll try to ask smg about pilot and air screws settings when pods and 4/1...
In my '79 gs 550 (VM22 carbs), I had to put larger main jets, and raise the needles... ok for them.
About pilot (fuel) and air screws, Do I have to keep the standard settings or adjust them to increase the air / fuel flow when idling to avoid dying at idle?
I mean, standard setting to have the good air / fuel setting is air screw -1.5 turn / fuel screw -5/8 turn. Do I have to put for example a similar setting (but with more amount of air / fuel) like air screw -3 turns / fuel screw -1.25 turn?

This is for pods and 4/1 exhaust...

thanks!

[Jlorello]

Hello i have a 81 450 with slip on jigh flow exhaust tips and pod filters i was looking at getting a jet kit from 6 sigma anyone bought from these guys wanted to know how there quality of the kits are

[TDC311]

I have a jet kit, I ordered from them about 2 years ago, in my 1979 GS 750E. I had re-jetted when I put generic ebay pods on my bike, but when one popped off and blasted me in the leg at like 70mph, I decided to invest in some K&N pods. However, in doing so my bike would not run with the now increased air flow so I wasn't sure what to do next and I needed an answer fast so I found the 6 sigma kit on ebay. They asked me about my exact location and modifications and sent me a kit tailored to my bike and atmospheric conditions.

The kit had easy to follow instructions and told you where to set the needle with the "e-clip" and everything. However the installation was really easy for me since I have the VM carbs, depending on your carbs you may need to use the drill bit that comes with the kit.

One interesting note about that kit from them was that they even thought about different jets for the inner cylinders vs the outer cylinders which I found really interesting. I don't remember them proving an exact explanation but I believe it would be due to the fact that these engines are air-cooled so the inner cylinders can get hotter than the outer so they provide slightly bigger jets for the carbs for the inner 2 carburetors. I am not sure if that is a normal practice or not.

They even provided an alternate set of jet sizes in case the first ones weren't quite what you needed.

[TxGSrider]

Hello.I have a question to the carburator wizzards. This is a dyno run from my GS750 1977 Uni filter pods, open exhaust. Pilotjet 15, Mainjet 117.5, fuelscrew 2 turns ,air screw 1.75 turn, needle one notch from downside. So needle can move one higher.
It runs not bad however runs a bit lean on the lower revs. Float level standard . What should I do to make it a bit better?
[ATTACH=CONFIG]46629[/ATTACH]

I don't have as much experience with jetting cv type carbs as most of the people here, but I have jetted several regular style carbs using a wideband. I know on a cv carburetor working correctly that the slide isn't open all the way until the engine rpms are high enough to use the additional air. So if your carburetor slide is less than fully open it is using the needle to regulate the amount of fuel entering the engine, I would sure try raising the needle and it should help.
And that is really lean at low rpms...

[Tarantulahed504]

Hey guys,

so ive got my bike torn halfway apart and just started to put here back together. 1978 gs750. I will be running delkevic 4-1 exhaust and K&N pods. I did a full carb tear down, cleaning, orings/gaskets/fuel tubes, re jet (120 main/17.5 pilot) and jet needle moved one notch richer.

I guess my question is: should I start with stock fuel and air screw settings as a benchmark or does anyone have a similar setup that really purrs through the gears, and is willing to share their settings as a better starting point

also I'm installing SS exhaust studs to replace stock bolts.. I've read that you go locktite stud to head , and anti seize on the nuts. Is this correct??

thanks for the space and your time
andrew r

[Steve]

No personal experience with your particular setup, but the general concensus is to go 1 turn out on the fuel screw (the one on the bottom) and 1.5 to 1.75 turns out on the air screw (the one on the side). After it warms up enough to run without "choke", use the air screws to fine-tune the mixture for best idling.

.

[Jmcb]

Perhaps a dumb question. But I have a 1978 gs550. Are there any aftermarket air filters that are perhaps a bit lower profile and smaller then the stock air box that do not require re-jetting?

[aclaytonb]

Not that I've found.