jets in GSX 1100

[HUM]

Hi all

 

I have the impression that it runs a bit too lean, the spark plugs are more gray than brown

but in deccellaration I have beyond 5000 backfire in muffler  see video

Test drive Video

setttings

gsx 1100e 1047 cc
yoshis stage 1 cams
36mm carbs from Efe arther clean

4/1  V&H classic  with racing baffle
original air filter with box
main jets 120
needle in middle
mixture 2.75 rotations

 

I think a bigger jets as 122,5 or 125 will help, what do  U thnk  or does anybody has

expirience ?

 

cheers 

Uli

 

 

[Gixer1460]

With modern fuels, plugs are more likely to be grey than brown - those in my daily come out near white and its running perfectly! And I wouldn't call - what was heard on the video - a backfire, just sounds normal for bike fitted with aftermarket can - they all draw a little air in and burn's with any unused fuel drawn through under high vacuum situations like decel., it wouldn't worry me, otherwise stick a wideband up the exhaust to check it definitively?

Edited December 9, 2021 by Gixer1460