Garble noise, lack of power; 80 GS850G

[MUBULLDOG]

Ok the 122.5 mains are on and did pilot jet tune. Idles around 1300 to 1400 rpms. When on the center stand (tank was off and set on prime) I could rev it up & hold at 6K (very smooth) and then settles back below 1500. Took it out for a spin and everything sounded good with good power all the way to 50mph. Then it started the "garble" sound and I could give it more throttle but it didn't help, just made it "garble" more. Below is the list of things I know;
1. With pods and 4 into 1 pipes & the 92.5 mains; runs up to 55-60 mph and starts the "grable" sound with no more power.
2. Pods OFF and 4 into 1 & 95.5 mains: runs up to 65-70 and starts to garble and no more power.
3. Stock airbox and 4 into 1 pipes & the 92.5 mains; runs up to 55-60 mph and starts the "grable" sound with no more power
4. Stock airbox and 4 into 1 pipes & the 122.5 mains; runs up to 50 mph and starts the "grable" sound with no more power.

PO put the pipes and cheap pods on. Not sure why someone would put 92.5 mains jets on.

Where do I go from here?

[tom203]

If someone put 92 mains in, maybe they got creative with needles also- any way for you to compare them against known stock ones?
By "garble", I assume you mean it appears to be choking as it gets loaded in mid range.

[tkent02]

What are the original main jet sizes?

You should be just a few sizes bigger...

[MUBULLDOG]

Tom, the sound is almost like a burbing sound, at the speeds I stated. Could the 4 into 1 pipes, that the PO install, be part of the problem?

[koolaid_kid]

Ok the 122.5 mains are on and did pilot jet tune. Idles around 1300 to 1400 rpms. When on the center stand (tank was off and set on prime) I could rev it up & hold at 6K (very smooth) and then settles back below 1500. Took it out for a spin and everything sounded good with good power all the way to 50mph. Then it started the "garble" sound and I could give it more throttle but it didn't help, just made it "garble" more. Below is the list of things I know;
1. With pods and 4 into 1 pipes & the 92.5 mains; runs up to 55-60 mph and starts the "grable" sound with no more power.
2. Pods OFF and 4 into 1 & 95.5 mains: runs up to 65-70 and starts to garble and no more power.
3. Stock airbox and 4 into 1 pipes & the 92.5 mains; runs up to 55-60 mph and starts the "grable" sound with no more power
4. Stock airbox and 4 into 1 pipes & the 122.5 mains; runs up to 50 mph and starts the "grable" sound with no more power.

PO put the pipes and cheap pods on. Not sure why someone would put 92.5 mains jets on.

Where do I go from here?

1. You need a DynoJet Stage III kit
2. Won't run right without any filter
3. You need a DynoJet Stage I kit, which is included in the DynoJet Stage II kit
4. See 3.
And you need either K&N or APE pods. Those pods will be almost impossible to tune.

[MUBULLDOG]

Hey tKent02, well the stock mains should have been 115, however what I removed have a 92.5 stamped on them. Everythin that I have read so far, and Steve (GS member), state that if you go to pods and 4 into 1 pipes, then you have to go up to 122.5 maybe 127. Steve's son has stock airbox with pipes and he installed 120 and his 850 runs good. Maybe I do need to take a look at the needles. As I said before, when I was running w/o the pods & the 92.5 mains, I could go up 65mph before the lack of power started. Plus the carbs started the burbing sound.

[MUBULLDOG]

Hi koolaide, you say that is won't run without filters. Well that's when it ran the best, up to 65-70 mph, with those weird 92.5 mains. So could have been running rich? With the other setups it seem to be choking out at 50-55mph. Also, I can't find the make nor model of the pipes that the PO put on. So could the pipes be incorrect or have something to do with this issue. Should I pull the muffler and run it and see what happens? Thanks

[MUBULLDOG]

Well talk about learning about carbs. After everything I found on this set of carbs and comparing the part numbers and jet sizes to the attachment (Suzuki GS Carb Database). I really thought that this set came of an early 80's (80-82) GS550. The mains; 92.5 with the 150 pilot air jets, the jet needles stamped 4BEL2, and I found out the correct name for the needle jet (stamped X-6). They are called "Primary-Bleed Type Needle Jets". GS member Billy Ricks replied to my post, "Needle jets look different", with a very informative link to a google book that shows this needle jet. The link is below and the info is on page 177. Oh yea, when I removed all 4 of throttle slides (to check the needle numbers), I found three X-6 and one X-5 needle. So 3 slides were a different length than the 1. Crazy way to learn LOL.

I have alot of new parts, here's what I have done to this set of carbs; Installed the following: 180 pilot air jets, 122.5 mains, 47.5 pilots, used the 4 matching throttle slides with X-5 needles (I lefted the 0.5mm shims under the needles). Going to put them on today and tune as best as possible. I don't have a carb synchronizer so that won't happen today. Take it for a spin and see if it has any power at 3/4 to full throttle.

Wow, it ran very nice! Started with the 2 1/2 turns off set, ended up about 1 1/2 to 1 3/4 of set.

Thanks to all the GS family for the info

[XXWoodmanXX]

What are the original main jet sizes?

You should be just a few sizes bigger...

For the 850G/850GL stock size is 115. 92 seems a bit anemic to me, unless they were looking for good long-range cruising with better fuel range per tank?

I am guessing the pilot air jets were smaller too? 160 or less I would imagine

EDIT: Just read above post....lol