Moves
Shift Gear boosts Klinklang's Speed by two stages and its Attack by one stage, letting Klinklang outspeed a good majority of Pokemon when boosted, making it an essential move for sweeping. Gear Grind is Klinklang's most powerful STAB attack and hits the foe twice, breaking past Substitutes, Sturdy, and Focus Sashes. Return has decent neutral coverage and hits Pokemon that resist Gear Grind such as Lanturn, Pyroar, Samurott, and Ludicolo. Substitute is very important for Klinklang to avoid any crippling status ailments such as burn and paralysis, both of which stop its sweep. Magnet Rise is another option which assists Klinklang in setting up on a lot of common Ground-types, such as Rhydon, Torterra, Claydol, and, most importantly, Steelix. Wild Charge can be used as a coverage option to hit Poliwrath, Pelipper, Mantine, and Prinplup, but this leaves Klinklang walled by Electric-types if used over Return.
Set Details
Maximum Attack EVs plus an Adamant nature allow Klinklang to hit as hard as possible, while 176 Speed EVs allow Klinklang to outspeed neutral-natured base 80 Speed Pokemon, such as Shiftry and Kabutops. The rest of the EVs go into HP to increase its overall bulk, making it easier to set up. Klinklang can customize its EV spread to outspeed even more Pokemon before a boost; 160 HP / 252 Atk / 96 Spe allows it to outspeed neutral-natured base 70 Speed Pokemon as well as base 95 Speed Choice Scarf users after a boost, while 40 HP / 252 Atk / 216 Spe lets it outspeed Adamant Pinsir. Clear Body prevents Klinklang's Attack from being lowered by Intimidate, as well as preventing the Speed drop from Sticky Web. Leftovers is chosen for passive recovery, allowing Klinklang to set up more Substitutes if needed.
Usage Tips
Generally, it's best to save Klinklang for mid- to late-game when its checks and counters have been sufficiently weakened. Bring in Klinklang against a Pokemon that cannot deal much damage in return, such as Scyther, Mesprit, or non-Heat Wave Xatu. Use Substitute against any predicted status move, against a Pokemon that cannot do much in return, or on forced switches. Substitute is also useful for scouting status moves, Leech Seed, and super effective coverage moves. Once the opposing team is significantly weakened, use Shift Gear to boost Klinklang's damage output, and choose the appropriate move to hit the foe with from there.
Team Options
Grass-types such as Lilligant, Shiftry, Cacturne, and Vileplume all make for great teammates, as they threaten Water-types that check Klinklang, such as Gastrodon, Lanturn, Poliwrath, and Quagsire. Fire-types, such as Magmortar and Pyroar, can cover the vulnerability to Steelix Klinklang gains when running Substitute instead of Magnet Rise; they are also helpful to block Will-O-Wisps and threaten Ferroseed and Vileplume, which are much easier to handle with Substitute. Additionally, Cacturne provides Spikes support for Klinklang, making it easier to sweep teams, and a useful Water-type immunity, which can cover the non-Substitute variant's weakness to Scald. Life Orb Samurott is a good partner, as it's able to break past several answers to Klinklang such as Steelix and Weezing. Mesprit, Xatu, and Musharna are also great teammates thanks to their ability to threaten Poliwrath, Weezing, and Garbodor. Mesprit in particular has access to Stealth Rock to support Klinklang, as well as U-turn to help bring it in safely, while also having Healing Wish to bring Klinklang back to full HP and rid it of any status conditions. Hex Rotom is an interesting partner, as it lures in Steelix and Lanturn, weakening them significantly for Klinklang. Scyther is able to switch in and threaten Fighting-types, as well as lure in Pokemon that Klinklang can use as setup bait, such as Mawile and Ferroseed. Scyther also has good synergy with Klinklang because of its immunity to Ground and resistance to Fighting and Klinklang's ability to cover Scyther's Ice-, Rock-, and Flying-type weaknesses. Powerful wallbreakers such as Archeops, Aurorus, and Life Orb Magmortar can weaken teams significantly, paving the way for Klinklang to clean late-game. Garbodor is a great partner, as it switches into Fighting-types relatively well and supports Klinklang with Spikes and Toxic Spikes. Toxic Spikes in particular pairs very well with Klinklang because it wears down threats that prevent a Klinklang sweep such as Gastrodon and Barrier Musharna.