GS550 VM carb mid pilot jet size

[Vloukole]

Hi guys

I would like to know how important the size of the mid pilot jet (air jet) is?
The thing is I cant find the correct size 50 pilot (air) jets. All I can find is 160’s.
My bike has pod filters, because I cant seem to find a complete stock airbox.
The weird thing is how rich the bike is running with these pods.
Main jets are stock 80’s and pilot jets are 15’s.
Needles are set at stock clip position.
I had to completely close the fuel screws at the bottom of the carbs just to be able to lean the idle out using a colortune plug.

Any ideas or advise would be appreciated

 

[allojohn]

By your setup description you should be running very lean, maybe your float valves are not closing... have you cleaned the carbs to forum specs?

 

[zed1015]

What make pods are they?
Cheap pods are well known for being restrictive or masking the air bleeds in the mouth of the carb causing rich running and power loss and this is most likely your problem.
You get what you pay for and should only use well known free flowing proven brands such as K&N, APE, PIPER, UNIFILTER etc.
Once you have an unrestricted inake you should fit air corrector jets to cure the off idle hesitation/flat spot and only increase the main jet size while leaving all other jets and needle position stock.

 

[Vloukole]

Carbs were cleaned to forum spec. Dipped, ultrasonic and new o-rings etc.
Yes the pods are no-names.
I will replace them with proper pods.
If I were to run without pods, my bike should be really lean? Just as a test?
I will report back.
Thank you

 

[Vloukole]

What exactly does the mid jet (50) do considering there is another pilot jet (15) just above?

 

[zed1015]

Yes the pods are no-names.
I will replace them with proper pods.
If I were to run without pods, my bike should be really lean? Just as a test?
I will report back.
Thank you

Yes! if stock jetting it will run lean without the airbox.
Quality pods should flow as much or almost as much as running open carbs or velocity stacks and offer little or no restriction.

 

[Vloukole]

What exactly does the mid jet (50) do considering there is another pilot jet (15) just above?

Any idea/info regarding this?

 

[Vloukole]

I ran my bike with no filter. Just around the block. The bike still bogs down and plugs are black/sooty.
It bogs at half throttle and up.
How is this possible with stock jets and needle position.
Idle to 1/4 throttle is fine. I used a color tune to tune the idle.
Fuel screws are at 1/2 a turn and air screws are between 1 1/2 and 2 turn out.
Could it be the emulsion tube o-rings that are leaking? They are all new.
Float height is set at 26mm.