1980 GS1000G Carb Tuning Help

[Phaedrus]

Hello.

My bike's getting a new lease on life after a minor accident and I'm back to tuning her carbs...

I was hoping to get a better baseline this time around. The first time around, I believe that my main jets were too rich for my setup:

4 to 1 Exhaust
DynoJet Stage 3 (170 Mains)
**** Pod Filters

For this tuning attempt, I modified the pods in order to remove the restrictive rubber on the boot and raised the jet needle a notch. This removed a bit of hesitation at ~3/4 throttle, but full throttle was totally flat. At 3/4 to full acceleration, she would plateau and after a few seconds she would either launch like a rocket, or stay plateaued.

This time around I'm going with:

4 to 1 Exhaust
DynoJet Stage 3 (165 Mains)
K&N Highflow Pods

Same jet needle height. I'm also rebuilding the carbs and thoroughly cleaning (again). My questions is: do any of you have GS1000s with these mods? Is reducing the main jet in this slight of an increment even worth it? Or, should I jump way down and try the Stage 1, 118 mains?

I've never tuned carbs before, so I'm not very confident in my plug readings...

Thanks for the guidance.

 

[landshark]

I have the same set up and went with the exact instructions in the DJ Kit, no hesitation at all.

 

[Phaedrus]

I have the same set up and went with the exact instructions in the DJ Kit, no hesitation at all.

Did you run the 170 mains or 165?

 

[landshark]

Did you run the 170 mains or 165?

I can remember? I did it a couple of years back. All i remember is that i went with the stage 3 instructions.

 

[Phaedrus]

I can remember? I did it a couple of years back. All i remember is that i went with the stage 3 instructions.

Hmmm... Last question: are you running K&Ms or Emgo/**** Pods?

I'm hoping the carb rebuild helps. Could be a gunked up passageway that's messing up my WOT...

 

[landshark]

I have the "Dual" Pod K&N's. One filter does 2 carbs.
My Carbs were fully cleaned the "proper" way, no short cuts.
Have you seen the Basscliffs Mega welcome?

 

[landshark]

http://members.dslextreme.com/users/bikecliff/

This isnt exactly the mega welcome, but this site will give you any info you need on our bikes.

 

[dorkburger]

Hello.

My bike's getting a new lease on life after a minor accident and I'm back to tuning her carbs...

I was hoping to get a better baseline this time around. The first time around, I believe that my main jets were too rich for my setup:

4 to 1 Exhaust
DynoJet Stage 3 (170 Mains)
**** Pod Filters

For this tuning attempt, I modified the pods in order to remove the restrictive rubber on the boot and raised the jet needle a notch. This removed a bit of hesitation at ~3/4 throttle, but full throttle was totally flat. At 3/4 to full acceleration, she would plateau and after a few seconds she would either launch like a rocket, or stay plateaued.

This time around I'm going with:

4 to 1 Exhaust
DynoJet Stage 3 (165 Mains)
K&N Highflow Pods

Same jet needle height. I'm also rebuilding the carbs and thoroughly cleaning (again). My questions is: do any of you have GS1000s with these mods? Is reducing the main jet in this slight of an increment even worth it? Or, should I jump way down and try the Stage 1, 118 mains?

I've never tuned carbs before, so I'm not very confident in my plug readings...

Thanks for the guidance.

azr recently started a thread that some contributed to listing bike mods and carb settings.
By the way, Is your handle derived from Zen and the Art of Motorcycle Maintenace?

 

[dorkburger]

Here it is.

http://www.thegsresources.com/_forum/showthread.php?225932-Carb-Jetting-List&highlight=

 

[Phaedrus]

azr recently started a thread that some contributed to listing bike mods and carb settings.
By the way, Is your handle derived from Zen and the Art of Motorcycle Maintenace? ... Here it is.

http://www.thegsresources.com/_forum/showthread.php?225932-Carb-Jetting-List&highlight=

This is awesome. Thank you. I don't understand why the DynoJet Stage 3 kit has you run 165/170 mains if most of these guys have "Stage 3" mods (4 to 1 / Highflow Pods), but are only running 115-130 mains... No wonder I lose all of my power at WOT... I'm gonna try the 118 mains and see what that does for me.

And, yeah, the handle is from Zen.

http://members.dslextreme.com/users/bikecliff/

This isnt exactly the mega welcome, but this site will give you any info you need on our bikes.

This is an awesome resource as well, thank you.

 

[dorkburger]

Im no carb guru, but have read that Mikuni and Dynojet #s dont represent the same sizing. Somewhere on this site someone posted a chart that cross refrences different makes of jets. I cant recall where it is though.......

 

[Phaedrus]

Im no carb guru, but have read that Mikuni and Dynojet #s dont represent the same sizing. Somewhere on this site someone posted a chart that cross refrences different makes of jets. I cant recall where it is though.......

Ah, well... That makes more sense. Still... http://www.vmaxoutlaw.com/tech/dyno-mikuni.htm ... The difference isn't as drastic as I'd expect. Sounds like the jets are engineered very differently though. So, that kinda makes comparing Makuni vs Dynojet sizes a wash...

Andddd, I'm back at square one...

 

[landshark]

Ill have a look at what jets are left in my kit when i get home, but if you havent cleaned the carbs properly yet you are chasing sh1t uphill.

 

[landshark]

Just checked, 170 mains.

 

[Steve]

Just checked, 170 mains.

If that is a Dynojet 170, it is the same as a Mikuni 160.

If that is a Mikuni 170, it is the same as a Dynojet 182.

.

 

[landshark]

If that is a Dynojet 170, it is the same as a Mikuni 160.

If that is a Mikuni 170, it is the same as a Dynojet 182.

.

Dynojet 170 is what i am using, sorry for the confusion.

 

[Phaedrus]

Dynojet 170 is what i am using, sorry for the confusion.

Interesting... Well. Step 1 is to clean the carb, the right way. Waiting on my rebuild kit to come now. Step 2 is to clean and reseal the gas tank. I think that the coating inside is starting to peel and some surface rust is getting into the fuel. After all that, We'll see how she runs.