SELKIRK PRO S1 VS FRANKLIN X-40: HEAT, COLD, CONSISTENCY

If you’ve ever had a ball crack on a cold night-or watched one slowly turn egg-shaped in the heat-you already know why “durability” is a misleading one-word spec.

Franklin X-40 is the ball I bring when I want zero drama at open play and the most predictable, familiar experience. Selkirk Pro S1 is the ball I bring when I specifically want its play style and I’m paying attention to temperature and shape.

My answer up front

If I’m walking into open play with strangers, I bring the Franklin X-40 because it’s the safest “everyone will accept it” choice.

If I’m playing an arranged session and I want a different speed/feel (and I’m watching for heat-related shape issues people warn about), I’ll pick the Selkirk Pro S1.

A common thread in r/Pickleball discussions is that open play is “always” or “almost always” X-40, and that reality matters more than most gear talk admits.

Quick spec snapshot

Here’s the cleanest way to compare these two pickleball balls without overthinking it.

What that means on court

Hole count and construction aren’t trivia-they show up in real points.

• With the X-40’s 40 precisely machine-drilled holes and one-piece rotational molded build, it’s designed for “true flight” and durability outdoors. In a typical outdoor rec game-serve, third-shot drop, then a bunch of crosscourt dinks-the X-40 is the ball most groups already know how to read.
• With the Pro S1’s patented 38-hole seamless rotomolded design, Selkirk positions it around consistency, durability, and aerodynamic performance in tournament play. In a windy outdoor match, that “aerodynamic performance” claim is the kind of thing you notice as fewer weird floaters when you’re trying to drive a ball through a crosswind.

The friction point: if your group is used to one ball, switching balls can feel “off” for the first game or two even if the new ball is objectively consistent. People adjust, but the adjustment period is real.

Consistency over time

Most players talk about durability like it’s only about cracking. I care just as much about the ball staying round, because an out-of-round ball can create the kind of strange bounce that makes a clean rally feel random.

Franklin X-40: predictable until it fails

Franklin frames the X-40 as a durable outdoor ball that resists dents and cracking and withstands hours of aggressive play on rough courts. In real use, that’s the scenario where it earns its reputation: outdoor courts that chew up softer plastics, long rec sessions, and the kind of pace where you’re hitting hard drives and counters.

The tradeoff is that players commonly associate the X-40 failure mode with cracking-especially when conditions get cold. When it fails, it tends to fail obviously.

Selkirk Pro S1: durability claims vs the shape debate

Selkirk positions the Pro S1 as a long-lasting tournament ball that maintains shape, with a 1-year no-crack warranty and claims of no deformation in tests. Community praise also leans hard into “no cracks or deformation even after heavy use in heat,” plus a solid feel and “true spin with no wobble.”

But the decision isn’t that simple, because r/Pickleball also contains a highly upvoted warning that S1s deform quickly in hot areas, and another comment noting Pro S1s are better for cold weather. Players also report S1s can go out of round faster than X-40s crack, and that’s the exact kind of durability problem that ruins consistency before you ever see a crack.

So over time, I think about it like this:

• Cracking is a durability failure you can spot and replace.
• Going out of round is a consistency failure that can quietly wreck a session until someone finally says, “Is this ball weird?”

That’s why I don’t treat “no-crack” as the whole story.

Heat and cold behavior

Temperature is where these two balls separate in the way players actually feel.

Heat: the out-of-round risk matters

The most useful warning I’ve seen repeated is simple: S1s can deform quickly in hot areas.

If you play on sun-baked outdoor courts, that’s not a theoretical issue-your ball can start the session fine and then, later in the same run, you’re getting a bounce that kicks sideways on what should’ve been a routine dink.

On the other hand, Selkirk’s own positioning and some community praise point the opposite direction: heavy use in heat without cracks or deformation. That split is exactly why I treat the Pro S1 as a “conditions + batch + expectations” choice rather than a universal default.

With the X-40, the heat conversation is less about shape and more about it being the familiar outdoor standard. If I’m playing in heat and I want the lowest chance of a weird, out-of-round bounce, I’m more comfortable defaulting to the ball most groups already trust.

Cold: cracking vs cold-weather preference

Cold is where the X-40’s reputation gets the most pushback: players commonly say X-40s can crack in cold.

At the same time, one r/Pickleball comment specifically notes Pro S1s are better for cold weather. If you’re the person organizing winter outdoor games, that’s a meaningful nudge toward trying the Pro S1-especially if your current routine is “bring extra X-40s because one might crack.”

The friction point here is social, not technical: if your group expects X-40 and you show up with Pro S1, you may spend the first few minutes negotiating the ball choice instead of warming up.

Speed and play style

This is the part most comparisons avoid because it’s subjective-but it’s also why some players switch.

Selkirk frames the Pro S1 around control, predictable flight in wind, and consistent spin with “no wobble,” with a solid feel off the paddle. That “solid feel” shows up most when you’re hitting fast exchanges at the kitchen: hands battles, counters, and quick resets. If you like a crisp response and you’re trying to shape the ball with spin, that’s the Pro S1 pitch.

Franklin frames the X-40 around true flight and consistent bounce for outdoor play, and it’s optimized for outdoor tournament conditions (it’s the official ball of the US Open Pickleball Championships). In a real outdoor rec setting-mixed skill levels, different paddles, different swing speeds-the X-40’s biggest advantage is that everyone already has a shared baseline for how it comes off the paddle.

A small tradeoff to be honest about: if you’re chasing a “softer feel,” both brands position these as outdoor/tournament-leaning balls, and Franklin explicitly notes the X-40 struggles in indoor settings where softer bounce is preferred. If your main court time is indoors, neither of these is automatically the perfect answer just because they’re popular outdoors.

Value and availability

I’m not going to pretend value is only about money. Value is also about how easy it is to show up, toss a ball to the server, and start playing.

The X-40’s biggest real-world advantage is availability in the social sense: it’s the ball people expect, and r/Pickleball regulars consistently describe open play as “always” or “almost always” X-40. That makes it the safest bring-your-own choice.

Selkirk is upfront that the Pro S1 may cost more than basic pickleballs, and that premium only pays off if you actually want what it’s doing (durability claims, wind-focused aerodynamics, solid feel/spin) and your conditions don’t trigger the deformation complaints.

If you want a broader shortlist beyond these two, I keep that in my separate roundup of the best pickleball balls in 2026-but for this decision, the “common ball” factor is a huge part of value.

Who should choose which

This is where I stop talking specs and talk about what happens when you’re actually on court with other people.

Open play

If I’m going to open play, I choose the Franklin X-40.

Not because it’s magically perfect, but because it’s the default. When a group has already been playing with X-40s all morning, bringing the same ball keeps the session smooth. You’re not asking four strangers to recalibrate their drops and drives mid-run.

If you want the deeper X-40-specific context, my Franklin-focused breakdown is here: Franklin X-40 outdoor pickleball balls guide.

Arranged group play

If it’s my group and we’ve agreed on the ball, I’m more willing to use the Selkirk Pro S1.

This is the scenario where “play style” matters: if you want that solid feel and the controlled, predictable flight Selkirk is aiming for, you’ll actually get time to adjust over a few games. The first game can feel different; by the second or third, most players settle in and stop thinking about the ball.

Tournament prep

Both balls are USAP/USAPA approved (as listed above), and the X-40 has the extra real-world signal of being the official ball of the US Open Pickleball Championships.

If I’m prepping for an event where I expect X-40-like feel because that’s what I see everywhere, I practice with X-40. If I’m prepping for a setting where Pro S1 is in play (or I simply want to train with its feel and wind-focused design), I’ll practice with Pro S1-but I’ll pay attention to temperature and check for out-of-round behavior during the session.

My decision checklist

These are the five questions I ask before I throw balls in my bag.

1. Am I going to open play? If yes, I bring X-40 because it’s the most socially “welcome” ball.
2. Is it cold enough that cracking is likely? If yes, I’m more willing to try Pro S1 because players specifically call it better for cold weather.
3. Is it hot enough that shape could be an issue? If yes, I’m cautious with Pro S1 because of the repeated warning about heat deformation/out-of-round.
4. Do I care more about familiar bounce or a different feel? Familiar and predictable for a mixed group points to X-40; chasing a specific solid feel/spin points to Pro S1.
5. Will we play long enough that “over time” matters? For longer sessions, I’m watching for the failure mode that ruins consistency first: cracks for X-40 in cold, out-of-round for Pro S1 in heat.

Pros and cons

Selkirk Pro S1

Pros

• USAP approved
• Patented 38-hole seamless rotomolded design aimed at consistent flight and aerodynamics
• Positioned for predictable flight in wind and “true spin with no wobble”
• 1-year no-crack warranty
• Community praise includes durability and solid feel off the paddle

Cons

• Can be a tougher sell at open play if your courts default to X-40
• Players warn it can deform/go out of round quickly in hot areas
• Selkirk notes you may pay a premium and give up a softer feel

Franklin X-40 Outdoor Pickleball

Pros

• USAPA approved for outdoor tournament play
• Official ball of the US Open Pickleball Championships
• One-piece rotational molded construction with PE material
• 40 precisely machine-drilled holes for true flight
• Widely accepted at open play; the “default” ball in many groups

Cons

• Players commonly report cracking in cold conditions
• Franklin notes it struggles indoors where a softer bounce is preferred

FAQ

Which ball is better for cold weather: Pro S1 or X-40?

Pro S1 gets the nod in cold weather because players specifically call it better for cold, while X-40 is commonly associated with cracking when it’s cold. If your winter sessions keep ending with a split ball, Pro S1 is the one I’d try first.

Which ball holds its shape longer?

X-40 has the stronger “stays round” reputation in the way open-play groups talk about it, while Pro S1 has repeated reports of going out of round in heat. Selkirk also positions Pro S1 as maintaining shape over extended play, so I treat shape as condition-dependent: heat is the big watch-out.

Why do some balls go out of round instead of cracking?

Cracking is a visible structural failure; going out of round is a shape/consistency failure that can happen without a clean break. On court, out-of-round is often worse because it creates strange bounces that look like mishits even when your contact was fine.

Which ball is more common at open play?

Franklin X-40 is more common at open play. r/Pickleball regulars consistently describe open play as “always” or “almost always” X-40, which is why it’s the safest ball to bring when you don’t control the group.