Unfortunately, another pod post

[LordJebus]

1979 GS850g carb help

Ive been messing with this bike for some time now, I bought it sitting for a year and the previous owner started converting it into a cafe racer, he was never able to get the bike tuned for power and I’m sure it’s because of the UNI pods installed. After cleaning the carbs, adjusting timing, taping the pods, color tuning, and syncing carbs I was able to get the bike to run smooth and recover the majority of its lost power, but it’s still extremely hard to keep that way so I built ITBs for each of the 4 carbs, only for it to tune for the perfect idle but be too restrictive for power or to lean for idle and still too restrictive for power. I need a jet kit for these pods but I cannot find anything 1979 specific, only 1980-83 from dynojet. Does anyone know if that’ll work? Or if I’m headed down the wrong path? Any help appreciated.​

 

[LordJebus]

Even though I have a 50:1 riding ratio (50 min labor to 1 minute riding), I still adore this bike, I mean, look at her.

 

[Big T]

No, that jet kit is for BS carbs. You won't find much for the 79 as it is a one year; only version
Your VM carbs are very tunable
What are your settings for pilot fuel, pilot air, pilot jet, jet needle and main jet?

How do you ride with no front suspension?

 

[zed1015]

For pod use, open carbs or stacks all you need to do is simply install air corrector jets ( main air jet conversion ).
This is the guaranteed proven solution.
Leave ALL carb settings, needle position, pilot jet size STOCK and go up a size from stock on the mains.
This will cure the off idle bogging / hesitation caused by the transitional lean spot and sharpen up the power curve to the red line.

Air corrector jet kit. Suzuki GS1000,GS850,GS750.MIKUNI.LEDAR.PODS,K&N,FILTERS. | eBay​

 

[Suzukian]

You drill drill out the main jets use number or letter, or fractional size drills. Between the three, they go up in increments of .001" inch. If you go to big, You can solder them, then drill back down.

 

[uk gs nut]

As Zed1015 said with VM carbs air corrector jets are the solution.

 

[chuck hahn]

Be sure the rims of the pods rubbers arent plugging any air jet holes or anything else

 

[unfocused]

Purchase a set of Wire Sized drill bits. My idle jet is the next drill bit size up 15 - 16 and my mains are ? hmmm, I just pulled a Mitch McConnell...

However, my air box looks like this...

 

[unfocused]

And then like this...

 

[unfocused]

One more view for those wondering...

 

[chuck hahn]

So my question is that if you're gonna stuff pods in a stock box why not just use stock filter. All this looks like a waste of time.

 

[chuck hahn]

Use the search feature and look for JOCKEYJOURNAL. I posted a jet size chart years ago. If I don't see you have found it when I get home this afternoon I'll try posting a link

 

[unfocused]

So my question is that if you're gonna stuff pods in a stock box why not just use stock filter. All this looks like a waste of time.

It's a factory air box... although it's not stock. It breathes a lot better than stock, obviously.
Also, it's sits in the factory location using the factory mounts. Sleeper...

May be a wste of time to you but my 844cc 750 engine actually enjoys it.

 

[LordJebus]

I love this forum, thanks for all the knowledge and help. The air corrector is a smart fix, I’ll be trying that as well as stepping up the main. And as for how do I ride with my lack of front suspension, the answer is I don't! I just bought new schrader valves and seals as the previous owner broke them in half installing the handlebar.

 

[chuck hahn]

heres the chart


https://www.jockeyjournal.com/threads/keihin-dynojet-mikuni-jet-size-cross-reference-tech.64769/

 

[Rob S.]

Doesn't the "air corrector" negate the benefits of wide open pod breathing?

 

[Cipher]

one more view for those wondering...

sleeper mod. No screwing with carb side. Genius.......
Reduveced chance of crosswind temp buggering intake balance.

Id see if any small footprint flat auto filters could be adapted.
Hell you could mod micture by sliding in varying porosities of media

 

[zed1015]

Doesn't the "air corrector" negate the benefits of wide open pod breathing?

No!
How do you come to that strange conclusion ???
You get the same unrestricted air flow without the associated off idle hesitaton / bogging and that's it..
The air corrector ( main air jet conversion ) targets the cause of the off idle lean spot without detrimentally affecting the rest of the fueling curve and power unlike the grossly ill concieved method of just throwing more fuel at the issue that continues to be inflicted by those who have no idea what they are doing.

A quick explanation..

When you remove or significantly de restrict the airbox, the off idle bogging / hesitation that results is caused by higher atmospheric pressure in the venturi and over the needle jet ( more air volume but moving slower ) ...
This impedes fuel delivery from the needle jet tube at just off idle rpms and creates a noticable lean spot which manifests as a drop in power around 2000 rpm.
Contrary to what many believe this is not a pilot jet or needle jet issue but on the transition between the two which is the area the air correctors have the most effect...
The misguided method of fitting larger pilots and lifting the jet needle as a "cure" only serves to over richen the entire lower to midrange fueling and mask the issue which also reduces mpg and top end power by up to 25% in the process..
The effect of the air correctors feather off proportionately as the revs rise which maintains the correct A/F ratio at higher rpms and results in a sharper throttle response, increased mpg and overall power by 2 to 6 hp on average.

If you look at Mikunis performance VM29/33 smoothbores that are designed to run open without an airbox you will see that they already have a main air jet (at 6 'o'clock in the carb mouth) to tackle this issue in exactly the same way.
This jet is available in several sizes to allow for very fine track adjustment.
( The later Mikuni TMR's etc actually have an air screw type adjuster for this rather than changable jets for quicker and easier tuning )
Unfortunately this jet ( BS30/97 ) is only m4 thread and the un-drilled air passage in the stock VM is already just over 4mm so they cannot be used.
For the stock VM i had to make them larger at m5 and the air passage simply needs tapping to suit.

 

[Suzukian]

zed1015​ based on what you posted, he would benefit by putting spacer plates to isolate middle carb.

 

[zed1015]

zed1015​ based on what you posted, he would benefit by putting spacer plates to isolate middle carb.

I have no idea what you are talking about. but at a guess. NO!