Went from 23 YZ450 (chassis and i didn't get along) now 23 YZ250f.....but need a little more

Ive heard dual injector and ECU from Twisted is good bang for your buck.

https://www.td-racing.com/product-page/yamaha-yz250f-2nd-injector-kit

Perhaps Athena's 83mm Big Bore kit may be something for you to look into?

What ever you do.  Get a twin air power flow kit, don’t want to suck dirt in and you will get more bottom end with the twin air. I had a 22 with a fmf pipe, get ecu and filter kit and bike was good.  Made more power everywhere.  So I’m sure porting and dual injections can do even more.  Just be ready to change out timing chains at like 15-20 hours. 

I'm also wanting a little more from my '22, but don't want to go into the top end. I'm standing by for a prototype product for the injector/throttle body. I'm told to expect pretty good gains. Should be a simple installation and offer the best value, considering the alternatives. Fingers crossed.

Nah, this device will attach at the throttle body and injector. Just as with Twisted, the target is improved combustion. Nothing related to the electronics. 

Keep us posted! Very intriguing ...

I recently rode a yzf 270 kitted bike that tzr did and it was amazing. I couldn't pull him on my 350 down a 4th gear straight. 

Big bore brah !

On my late RMZ250 I was really surprised how much difference a Twisted Vortex made over the most aggressive map in the GET programmer. I called Twisted thinking I wanted head work but they said I really should try their Vortex first. I thought it was just a sales pitch but after going that route I was definitely mistaken. 

Wouldn’t be doing shit untill I put a CW1 rod on that crank…

What are you looking for exactly.

More bottom, top, 3rd gear to pull longer.

Better, calmer drive where the yz doesn't feel jerky/unsettled.

Being that tall I highly recommend some lower foot pegs if you havent already.

Get the works connection peg relocation mounts if you already haven't. I'm 5'6 and I'm in-between if I like them or not but every person over 5'9 has love them.

For the motor having built a motor on this bike this is the order I would do things.

I needed to just get some more top end and smooth out the jerkyness of the bottom end at the initial crack of the throttle. There was sections were 3rd was not quite enough and would make the bike feel bound up but the shift to 4th on the face of a couple jumps was no fun cause if I had a Lil bog or a not clean shift I would clip my rear wheel on a peak landing.

1st. 49 tooth rear. Will smooth the bottom a touch and give you a little longer 3rd gear.

2nd. Dh1 or twin air filter with gytr boot.   This will give you a bit of response and bottom back from the 49 tooth. It also give you a bit more power in the top. It doesn't seem to pull longer just has a more power from mid up. One thing to make sure to do is the black hard plastic airbox PC in front of the gas cap is cut the small triangles out of it. That opens up the air box to get more air in. I didn't know this until I read the instructions 2 months later. When I did the filter cage and boot I felt a difference and when I did the cut out I felt a difference again.

3rd. Vortex and or fuel. T4 or equivalent. Fuels will give you a bit better response. I use Suncoast pump 260gtx+ mixed with  3.5 to 2. My jugs can fit an extra half gallon. Comes out to 7.10 a gallon and it dyno'd very close to T4. 

With the ignition power wise I definitely felt more in the mid and it pulled longer on top. I did ask for  a smoother initial throttle to again help with the bike pitching when you get on the gas in corners. An a little less engine braking. At this point I don't feel like I'm giving up a shit ton on most starts in the 450B and vet classes. Longer starts it is what it is. 

Lastly would be motor work. Ported head and a HC piston will give you all you need. But at this point I strongly recommend giving my old boss Phil at crank works a call and having them rebuild and balance the crank with their pro rod. I still have one of the initial rods we made in a 08 kx250f with over 400 hours on it and all its needed so far is bearings and new bushings.

On my bike I went whole hog.

Ported,  PC cams valves/springs 270 kit B piston to tighten up the clearance with a thinner gasket to up the compression crank from phil with a bunch of extra work on it. Torque drive clutch plates with Hinson hub and pressure plate polished Trans and 2nd injector. Rocket exhaust for more top. An yeah she fucking hauls ass now. Way more then I need but hauls as from 3/8 throttle to wfo. The biggest thing is the connection to the rear wheel it digs in and pushes you forward with out feeling like it's spinning the rear at any point at every point of the throttle your getting exactly what your asking for. I might try 48 and see what that does.

Hope this helps a little.

Can I ask this?:

Are people trying the Yamaha Power Tuner  and trying different mapping that's FOC, before they dive into spending $$$$. They come free with the YZFs, don't they? 

Look, I ride my old beast mostly, but do get to ride quite a few other bikes that are not my own, having been in the industry for over 50 years now. And, am invariably impressed with newer model bikes each time I get on them. 250Fs surprise me every time, and they get better each year. Though, I'm not one that is as Rev happy as you have to be with them. It's why I suggested the  Athena Big Bore - I just find 250Fs a bit lacking in grunt when weighing them down with my Bear Body.

I've a mate that works for Yamaha, and, he says he sees so many people who Don't even try the Yamaha Tuner - they go straight to Vortex / GETs etc. Yes, it's their money, but to not try something that, in my (limited, admittedly, but I've gone through it with him a few times, and have found marked changes) experience, can make a very noticable difference in performance, seems strange to me. It's like the people who would not try the few seconds to a minute or two of either changing the PV spring tension, or Spring type on the KTM 250 /300 2ts. Cripes you could make them mild, to wild so , so easily.

Said mate sets his suspension, Has a wide selection of Tyres for whatever conditions he's riding in, does a Airbox / Filter mod ( opens it up / or a new top, and a cage and filter) , a slip on Muffler (mainly, he says for weight)   the Tuner settings, and is but a second or two behind his Team riders on practice laps - well, for at least , or the most, a couple of laps. He is over 50, after all, but a blazingly fast rider before he runs out of puff / comes to his senses.

I'm not criticizing - people can spend whatever they want, and doing so keeps things going, but I do wonder if people are trying the available standard options, before they go for the aftermarket bits. 

Got any details or other info on it? 

What info are you looking for ? 

Didn’t know if you had the details on the build. I’m assuming it had a ported head to go along with the big bore, but cams? Second injector? Stuff like that.

I’m on a 350 now but I am curious. Thanks!