Which carburetor needle to choose, I need your advice.

[Batlet]

This is my first post, before writing it I searched the forum and maybe I didn't look properly, but I didn't find the solution.
I'll explain my problem. When I bought the Vmax, I took it apart piece by piece, cleaned it, painted the frame, engine and rims , changed all the engine gaskets, adjusted the valve seats and then adjusted the valves. The engine was perfect. The carburettors were cleaned and the gaskets were changed. The engine runs perfectly, sounds perfect, but it doesn't run well in the mid-rpm range.
I know the problem is with the carburettor needles, the bike runs dry in the mid-rpm range. I changed the position of the needles from P3 to P5 and it improved a little, but it still fails in the mid-rpm range. Right now I'm wearing the 5DZ19 needles, I also have the 5EZ50 and 5EZ43 needles but the last two are not adjustable in height, they only have one clip position. I have also tried them and the problem continues.
I have seen different needles on the forum, and by the shape they have, I think that the ones I should install are the Dinojet Stage 7. Do you think that will solve the problem?
Remember that my bike is European, it has a 2EN engine with the Vboost system installed. At low speeds it runs perfectly and at high speeds it runs like hell, it seems like it will tear your arms off. The high and low jets are the European standard.

Thank you in advance.

 

[Fire-medic]

On an internally-stock engine, I've had good luck with the Dynojet Stage 7 needles, and 147.5 mains. Miami is at sea-level (for now).

 

[Batlet]

Thank you very much for your advice.
I would like to ask you a few questions.
I live in Mallorca, a small island in the middle of the Mediterranean Sea, with quite pleasant temperatures, I think the climate is very similar to Miami. In what position do you have the Stage 7 needle?
Right now I have a 150 main jet, and the bike runs perfectly at high rpm, do you think I should order the 147.5 or should I first try with just the needle and then change the main jet?
Do you know the references for the Stage 7 needles? I suppose that with these references it will be easier to find them.

Thank you very much again

 

[MaxMidnight]

Attached are the instruction for fitting the DJ S7 which has the part numbers of the components.

Is there somewhere you could get it on a dyno so you had factual data to work on? (Aw c'mon, you would have been disappointed if I hadn't asked! )

 

[Batlet]

I found this:
https://www.dynojet.com/jet-kit-for-1985-2007-yamaha-v-max-4716-1/

But its incredible price for 4 needle and 8 main jet, its crazy

 

[apsolus]

I found this:
https://www.dynojet.com/jet-kit-for-1985-2007-yamaha-v-max-4716-1/

But its incredible price for 4 needle and 8 main jet, its crazy

im going to try shimming the needles out with small washers. make sure they fit in the caps the needle sits in propelry. that kit sure is pricey!

 

[Batlet]

There isn't a good Samaritan around here with 4 needles to sell, right?

 

[Tom Determan]

im going to try shimming the needles out with small washers. make sure they fit in the caps the needle sits in propelry. that kit sure is pricey!

I can't recall where we bought them but there are kits available with different thickness shims that go under the clip so you can get exactly where you want to be by varying the shim. (Assuming your needle has the correct taper for your engine and tune set up.) We did it on our sleds with data collection systems that collected throttle position, RPM, EGT, all the inputs one needs to nail the A/F ratio where you want. Try all the parts houses for "Mikuni shim kits". Then think about where your throttle will be most of the time. Without a dyno and measuring A/F or EGT, I don't know how you can get really dialed in across the full range of operating conditions.