Needle shims vs Clip

Hello everyone, Im wondering what I should expect to add a 0.5mm shims vs moving clip on my Vm28ss !? If Im at 13 afr middle throttle. What you think I could get with dropping the clip vs shimming needle ? Thank youu

In general, one notch up or down on the needle will affect fuel flow as follows:
At 15% throttle valve opening you will get +/- 3% to 6% more/less fuel for each step
At 50% throttle valve opening +/-5% to 8% more/less
At 75% throttle valve opening +/-1% to 2% more/less


The above info comes from a Mikuni manual 
 

Oh I see.:Thats a good step!! Thank youu

Maxbou92 wrote:

Hello everyone, Im wondering what I should expect to add a 0.5mm shims vs moving clip on my Vm28ss !? If Im at 13 afr middle throttle. What you think I could get with dropping the clip vs shimming needle ? Thank youu

What are you trying to achieve ? 13 is ideal for AFR

Hum, next summer I switch to real K&n pods. My afr at 4000rpm is approximately 16 .. so I thinking about shimming my needles and put all the same main jet size!! Now I have 102.5 1-4 and 105 2-3. I will put 105 everywhere..  1-4 are lean a bit if you remember the colors on my last post!!?

So are you saying the FR is 16 (way too weak) at 4000 then drops to 13 at mid throttle ? what is it above and below these points ?

The dyno graph(wot) start at 4000 (16afr) 5000(13.9afr) 6000-10 000 (12.5-13.07afr)
maybe real pod will help me ?!

Maxbou92 wrote:

The dyno graph(wot) start at 4000 (16afr) 5000(13.9afr) 6000-10 000 (12.5-13.07afr)
maybe real pod will help me ?!

So from around 5000 upwards all looks good so main jet is fine, lifting the needle may help lower down but don't forget as mentioned before, snapping the throttle wide open from low revs will cause a momentary "lean" condition with carbs while the jets try and catch up with the increased air flow. Before you change anything I would suggest getting readings at a constant 3000 - 4000 - 5000 rolling the throttle on not snapping it open

Thank you, if I put 105 everywhere. Will it change top end afr(too rich)?!

Maxbou92 wrote:

Thank you, if I put 105 everywhere. Will it change top end afr(too rich)?!

it will change the top end but not by much, I would fit your new filters, even up the mains then see where you are. AFR is a great way to see what is happening but try and measure it under normal riding conditions as opposed to WOT power runs

Okay!! I will put 105 everywhere
thanks a lot
 Merry Christmas to you all