Do pipercross air filters really flow better at all?

[lucasg.03]

I’m getting my dt125re dyno tuned and was considering the pipercross air filter just to make sure everything’s dialed in before hand. Do they actually flow better even if it’s just a tiny bit? As I noticed they appear to be the same shape and both made of foam

[Calum]

You'd be better focusing on getting a DT230 Lanza Snorkel as it's slightly larger flow.

https://www.cmsnl.com/products/duct_4tp1443700/

Or a cheaper easier solution is to 3D print a larger snorkel.

[lucasg.03]

@Calum I believe a previous owner removed the snorkel, shall I leave as is? As tune may compensate for air velocity lost to an extent

[Calum]

Removing the Snorkel will adversely affect the performance. Removing the snorkel will result in turbulence adversely affecting performance.

So put the snorkel back in.

[HOTSHOT III]

@lucasg.03 I wouldn't go for a Pipercross air filter element to be honest, the stock one is perfectly adequate if properly maintained. Interestingly I once bought a Twin Air DT125R element which was a bit too small to fit over the plastic cage properly, meaning the base wouldn't seat where it's supposed to seal against the airbox body.

I've also noticed some "tuners" on the DTR Facebook pages saying foam filter oil restricts power output. This is most definitely NOT the case; compare the surface area of the air filter element with the 28mm carburettor bore and there's no way a properly oiled filter could measurably reduce airflow.

You're better off getting 3-4 Yambits air filters which are just as good as stock but half the price; then establish a routine for cleaning and re-oiling them. Put the clean oiled ones in a plastic bag and you can quickly throw on a fresh one after every wash/off-road ride. Jet washing the bike and not changing the air filter/going for a short ride is a leading cause of ruined crankshafts on two-strokes, you only need like half a cup of water to creep in to knacker the mains/big end. And a clean air filter cuts down on a lot of other aggro; you see it all the time with RC car racing. Because a 1/8th buggy air filter is only the size of a 35mm film capsule it starts to affect throttle response after about 7 minutes on a dry dusty track. A lot of the guys at my local club used to try and play the Big I Am Tuning Wizard by endlessly twiddling the mixture screws but all they were doing was reducing the flow of fuel to match the reduced air flow (i.e less power). Whereas changing the air filter = getting your hands dirty; no cool points for the Bloke Down The Pub even though it means the engine just runs well and doesn't suck dirt right through the day.
Also the DTR airbox is poorly sealed where the carb-to-airbox boot meets the airbox (i.e downstream from the filter); it can be very helpful to seal this up with a product called Seal-All which is a petrol- and oil-resistant glue. You really need to remove the airbox completely to do this which means the shock needs to come out but this is easier than it sounds and you get to grease up the linkage bearings at the same time.

https://yambits.co.uk/dt125re-air-filter-p-9241.html

https://www.repairingproducts.co.uk/.../seal-all-gas-oil.../