Running out of parts to change!!

[Meweeble]

I've posted a couple of times about this problem and thanks to everyone who has helped. I took everyone's suggestions and this is what I've done so far.

1979 GS1000 (Initial problem, no power off idle can't adjust carbs very well)

- Dyna S ignition and coils
- Cleaned all connections but did coil mod anyways
- Complete carb rebuilds (soaked, all o rings changed)
- Dynajet Stage 3 kit
- Broke down and bought new intake boots (when I changed boots I checked carbs again, no visible issues)
- Just finished valve adjustment (all shims had to be changed, pretty much 0 clearance)
- Synced carbs

OK everything I did helped a little, but I still have the same problem.... no power off the line and carb adjustments don't help much if at all. There is something I just noticed today when I was sinking the carbs, I tried to adjust the fuel mixture valve (the one on the bottom) turned it off on 2 carbs and the bike still idled. The inside of the carbs (on the filter side are fairly damp with fuel, so it's coming from somewhere).
Not sure if you can see from the pic?-----
Question--- the only thing I didn't change in the carb is the fuel by pass plunger (just changed the o ring at the top) could this account for the issue? It's Other than this I'm out of ideas.

 

[Guest]

Hey there, I havn't followed your previous threads but thought I'd mention a couple of things that have caught me out in the past.

Maybe check that the choke plungers aren't being held open - I do this by making sure the plastic part that gets lifted to open the choke can spin around when the choke mechanism is fully closed (hope this makes sense). If they're slightly open then that may explain your fuel screws not affecting idle. My bike stalls if I shut any one of the fuel screws completely. Are you getting any black smoke when the bikes fully warmed up?

No power off the line can be from being too lean on the pilot settings or the needle depending on how you use the throttle. If it bogs down then takes off it's usually rich. If it just lags then slowly picks up speed then lean. This is just my observation from many mistakes.

Something blocked or not right in the pilot circuit can stuff up your settings everywhere else and drive you crazy. Sort that out and the fuel screw/idle situation first. You may have to pull your carbs apart and just go everything again - make sure everyone of those sneaky passages is clean.

 

[Big T]

While you gave us a good run down of what you did, you didn't mention what you have

Header?
Pods?
Main jet?
Pilot jet?
Fuel screw setting
Air screw setting?

 

[koolaid_kid]

I suggest rechecking the float level. If that does not help, you may need to redo the carb rebuild. Since all the o-rings are new, you won't need a new kit if you don't tear them when you remove them.
You must have headers and pods with a Stage III. Unfortunately, DynoJet does not have an install pdf for that model. What jets were provided and what is currently in the carbs? Where are the needles set?

 

[Meweeble]

Thanks,

OK this is what I have in it now...

- 4 into 1 header
- Pods (off right now)
- Stage 3 (4th notch down)
- 142 main jets
- Pilot jet 1.5 to 2
- Fuel mixture jet is at 1 now
I did take the carbs apart again when I changed intakes last week, all looks good all passages clear as far as I can tell. I checked the floats too and they are still spot on.

Today when I was syncing the carbs I used about 2 litres of fuel in about 15 minutes (seems like a lot to me) It does bog when taking off, 3-4k rpm and up runs well (took it for a spin). No black smoke but the plugs are black. I`ll check to see if the plungers are seated tomorrow.

 

[Suzuki_Don]

You didn't mention what size pilot jets you have. The pilots control just off idle.

Standard pilot jet for this model is #15. What do you have fitted now.

 

[Meweeble]

You didn't mention what size pilot jets you have. The pilots control just off idle.

Standard pilot jet for this model is #15. What do you have fitted now.

Just the stock ones that came with the K&L kits.

 

[Mop Bucket]

I had my idle screw in to far and the bike wasn't responsive when I twisted the throttle. I backed the throttle down and turned out the idle screws a half turn each and improved throttle response.

 

[850GT_Rider]

Thanks,

OK this is what I have in it now...

- 4 into 1 header
- Pods (off right now)
- Stage 3 (4th notch down)
- 142 main jets
- Pilot jet 1.5 to 2
- Fuel mixture jet is at 1 now
I did take the carbs apart again when I changed intakes last week, all looks good all passages clear as far as I can tell. I checked the floats too and they are still spot on.

Today when I was syncing the carbs I used about 2 litres of fuel in about 15 minutes (seems like a lot to me) It does bog when taking off, 3-4k rpm and up runs well (took it for a spin). No black smoke but the plugs are black. I`ll check to see if the plungers are seated tomorrow.

Are you trying to sync the carbs without the pods or airbox?

 

[Meweeble]

Are you trying to sync the carbs without the pods or airbox?

Yes the pods are off right now, I still have the carb sync hooked up... Oh I forgot to say that the bike also has a 1085 big bore kit on it.

 

[MisterCinders]

Put the pods back on. That way you can start it without burning up your engine with too much air.

 

[Meweeble]

Put the pods and the top of the carbs back on, carbs still in sync. It's running crappier now.... tried to adjust settings.. no improvement. I had a thought... I did check the floats again when I changed to new intake boots and they were still at 24mm. When I rebuild the carbs I put in new float valves and had to adjust all the floats as they were different than before. Could possibly the new valves require a different float height? Could the 24mm setting be too high and I am getting a way to rich mixture? I just ran a litre and a half of fuel through in about 5 minutes ideling and when it ran out it started ideling real nice for a few minutes.

 

[koolaid_kid]

Sounds like your float levels are too high. Are you sure you are measuring at the correct places on the float and the carb body?
I am only asking because I have rebuilt 2 sets of carbs I purchased from other persons. Both had the float levels incorrectly set, which allowed me to get some bargains.

 

[BassCliff]

Hi,

Just the stock ones that came with the K&L kits.

The aftermarket "carb kits" are infamous for inferior and incorrect parts. If you need to replace any internal carb bits then I suggest you use OEM parts. When you dipped the carb bodies you should have dipped all the other metal parts (needle jet, pilot jet, needle valves/seats, air jet, etc) and re-used them along with a new O-ring kit. The manufacturing tolerances (or lack thereof) on the aftermarket "carb kits" can cause issues that are hard to troubleshoot. The OEM stuff may be a little pricey, but it just works properly.


Thank you for your indulgence,

BassCliff

 

[Guest]

I just ran a litre and a half of fuel through in about 5 minutes ideling and when it ran out it started ideling real nice for a few minutes.

This does point to fuel level. Check the "wet" fuel level with some clear tubing. should be approx 3-5mm under the mating line of the carb body and float bowl.

http://www.z1enterprises.com/Fuel-Level-Gauge-Tool-Kawasaki-Suzuki-4160.aspx

 

[Meweeble]

This does point to fuel level. Check the "wet" fuel level with some clear tubing. should be approx 3-5mm under the mating line of the carb body and float bowl.

http://www.z1enterprises.com/Fuel-Level-Gauge-Tool-Kawasaki-Suzuki-4160.aspx

Ahhhh ya that's a great idea. I'll make one and try it. Hopefully I'll find the fuel level is too high, if not it's strip em down again cause I got nothin else left. Thanks for this tip!!

 

[Meweeble]

Hi,



The aftermarket "carb kits" are infamous for inferior and incorrect parts. If you need to replace any internal carb bits then I suggest you use OEM parts. When you dipped the carb bodies you should have dipped all the other metal parts (needle jet, pilot jet, needle valves/seats, air jet, etc) and re-used them along with a new O-ring kit. The manufacturing tolerances (or lack thereof) on the aftermarket "carb kits" can cause issues that are hard to troubleshoot. The OEM stuff may be a little pricey, but it just works properly.


Thank you for your indulgence,

BassCliff

I did keep all the parts and they all looked fine, but I used all the shiny new pieces from the kit. If it's not the floats I'll tear them down and re do them. Thanks

 

[Meweeble]

Just an update... wet checked the fuel levels and they all were at or above the mating surface of the bowl and body. So it looks like fuel levels were too high. Haven't adjusted the floats yet but I will this weekend and see if that works.

Thanks,

Kevin

 

[Guest]

One of my floats ended up at 28mm to get the wet fuel level right. I imagine they must get less bouyant with age.

 

[bwringer]

One of my floats ended up at 28mm to get the wet fuel level right. I imagine they must get less bouyant with age.

No, they don't.

The foam floats generally last just about forever, but they can get physically or chemically damaged and soak up fuel.

You need to replace that float, and check the others carefully to make sure they all float identically.

If you have a sensitive postal scale (down to 1/10 gram), you could weigh the floats to make sure they all weigh the same. Or, put the floats in a small amount of gasoline in a glass jar and make sure they float at the same height and attitude.