Thoughts on Jetting for Aftermarket Exhaust

[Clanky]

Hi,

I recently added a stainless exhaust and R6 exup end can to a FZR400 3EN1. Unfortunately electrical repairs after a burned out VR put a delay on fine tuning the carbs until now. After getting used to the new set up the main issues with the performance are bogging above idle and below 4000 rpm and a bit flat in the mid to high end ranges.

Today I lowered the needle clips from position 4 to 3 and the mid range is spot on now. Top end still flattens out so I reckon I need bigger main jets to compensate. Currently has 92.5 and 90 mains in cylinders 1 & 4 and 2 & 3 respectively so I am thinking going up to 95 and 92.5.

I think the bottom end bog is down to being too lean (I don't think this is a float height issue). Maybe a bigger pilot fuel jet is needed. Currently I have 30s but it looks like a lot of 3ENs use 35s. The pilot air jets are 115s which I think are the correct size.

Current settings are:

Stock air box with K&N filter
92.5 and 90 main jets
52.5 starter jet
30 Pilot fuel jet
115 Pilot air jet
Needle clip 3 of 5
Float height 24mm
2 1/2 turns out on the air screws
Carbs balanced

Carbs have been fully stripped and cleaned this week so I have no reason to doubt their operation.

Any tips or pointers to save me a potential ball ache are welcome

[willandrip]

Clanky ,I have a 3EN1 parts manual

90 & 92.5 mains.
%2.5 starter
35 pilot
125 pilot air

First time I have needed to refer to this manual !

[Clanky]

Cheers Will, that's very helpful.

I always thought that the pilot jet sizes on mine were stock but seems not. I'll go with the 35/125 pilots and let you know how it works out.