Best pipe for low-mid gains 350

I would say save your money and skip the pipe.. Buy a vortex ignition mapped by TD with your requests. Just my 2 cents

Also if you’re not already run the 2 stroke air filter cage and the vented side cover as that helps a bunch. 

HGS without a doubt. Cheap and effective and header developed for the 350. Most others offer their 250 pipe.

Bingo

HGS

i had an fmf full system on my 22, it almost just felt like it freed the engine up. it would pull 3rd in the corners better and rev quicker. i got it used for a good deal but i dont think it would be worth spending full price on one. put a 2018 airboot on it, you can get them cheap and according to jamie ellis is good for 1 ft lb on the torque curve.

Are those loud ? 

The best way to get more low-mid out of 350 is to just get a 450 in the first place. 

I did these exact mods and a remap from Twisted on my 350. It's stronger in every part of the power, and I have no desire for anymore. It's as perfect as can be. 

As others have indicated, a Vortex mapped by Chad - XPR or Jamie - Twisted is much better than any pipe.  Talk to either and ask if they can get close to exactly what you need.  Couple in the 2 stroke filter cage, 1 or 2 tooth up on rear and make sure to run the vented side plate everywhere but super sandy tracks and you should be be good.  

450sxf

The 450 brigade can't help themselves.

I call them the "I mostly idle around the track because I'm tired after 3 laps crew."

As opposed to the “I mostly idle around the track because I’m old” crew 

Touche 

LOL

I do understand the appeal of a stock 350, but asking for more low-mid power is exactly what a stock 450 would give you, so why not just buy the 450?!

I went up to a 53 tooth rear sprocket and cut the air box cover inside the hand hole so it's not visible. Also got a map switch(you probably have one/I have the gasgas and had to buy one), and map 2 is much better than map 1. Sometimes I still just gotta rev 2nd gear longer instead of using 3rd. It's just not a 450. Spring fork conversion gave me enough confidence to not be as slow in the turns (i have never been fast).

HGS is dutch and are mostly aiming for the European market so they aren't very loud. If you combine the HGS with a new vortex ECU (mapped by someone who knows something about it), your bike will be doing just what you want.

I just put an xpr mapped vortex on my 23 350 and it made the bike run very well. The power is very smooth but it just runs so much cleaner down low that I can lug the bike much better. It decreased engine braking and I can't believe how tight of corners I'm able to run 3rd and it will just pull it. 

Flawed thinking in the same way that saying a beefed up 125cc is the same as a 250F - pretty different methodology. You can't ride a 450 as aggressively you can a 350 (basically a big 250). Go Harder, Longer, Deeper on a bike with less rotating mass like the 350.

pipes dont have the effect that they provided a 2 stroke.

cams or ignition is where its at for a 4 stroke

HGS is a good pipe for that, but to be honest quality is shit. It doesn’t fit proper on those bikes and worn out pretty quick. It’s also an European brand so don’t know if it’s easy to get you’re hands on. 
 

Like above said, a well mapped Vortex will be doing a better job than just a pipe. I should go for that and in a later stage ad an  pipe…

It’s not so much just the power that makes the 350 better and more fun to ride. How the 350 engine feels in the chassis and how much better and lighter feeling it is, is what makes it good in my opinion. Farther revving and less inertia, quicker and easier side to side, less shifting. Not really lack of power. My post might not make sense lol

https://www.bestdualsportbikes.com/grunt-exhaust-manifold-ktm-husky

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