Trotters and pacers are harness horses that race at different gaits. A pacer moves the front and hind leg on one side of its body forward as a pair; a trotter's legs work in diagonal pairs, the left foreleg landing with the right hind leg. Every Australian harness race is programmed for one gait or the other, and pacing races fill most of the card.
For a punter the gait changes three things: how a race starts, how often a horse breaks into a gallop, and which times you can compare. In Harness Racing Australia's (HRA) results for July to September 2026, 16.9% of trotting starters broke stride at least once, counting breaks in the score-up, against 4.4% of pacing starters. The wider picture of the trots sits in harness racing betting.
The two gaits, and how to spot each
Both gaits belong to the same breed, the standardbred. What separates them is the order the legs move in.
| Pacer | Trotter | |
|---|---|---|
| Legs that move together | Front and hind on the same side (lateral) | Front and hind on opposite sides (diagonal) |
| Side-on, the two legs nearest you | Swing forward and back together | Move in opposite directions, front reaching while hind drives back |
| Usual gear clue | Hopples, straps tying each foreleg to the hind leg behind it | No pacing hopples, which would fight the gait |
| What the race conditions print | PACERS | TROTTERS |
The quickest check is the race itself. HRA's fields and results state the gait in each race's conditions, so you do not have to judge it from a replay. The exception is a trotter entered in a pacers' race, which HRA's handicapping rules allow (rule 9.1). A horse's gait can be changed, but only on an application under rule 97 of the Australian Harness Racing Rules (AHRR), and not until the horse has trialled to the stewards' satisfaction.
Why pacers fill most of the card
HRA's national statistics show how lopsided the split is, and how it has moved:
| Season | Trotting races | Share of all races |
|---|---|---|
| 1991-92 | 570 | 3.72% |
| 2015-16 | 1,353 | 9.51% |
| 2025 | 1,661 | 11.91% |
The card follows the horses racing. In HRA's results for the 414 TAB meetings from 1 July to 30 September 2026, 28,061 of 31,633 starts (88.7%) were in pacing races. Victoria ran 264 of the 429 trotting races in that period.
Two things favour the pacing gait. Pacers race faster, and they break far less often (the break counts are below). The speed gap shows in HRA's Melton track records (checked October 2026): over 2,240 m from a mobile start the pacing record is 1:51.1 and the trotting record 1:55.4.
That 4.3 seconds a mile is a big margin. Over the trip, 111.1 x 2,240 / 1,609.344 = 154.64 seconds against 115.4 x 2,240 / 1,609.344 = 160.62 seconds, a gap of 4.3 x 2,240 / 1,609.344 = 5.985 seconds. When the pacer reaches the line, the trotter still has that gap to run at its own 1,609.344 / 115.4 = 13.95 m a second, so it is 5.985 x 13.95 = 83.5 m behind.
Rating rules reflect the gap. When a trotter races pacers, Harness Racing Victoria's guidelines (clause 13.1, checked October 2026) class it far below its trotting rating:
| Trotting National Rating | Pacing class it races as |
|---|---|
| 55 to 85 | 55 |
| 86 to 100 | 60 |
| 101 to 110 | 65 |
| 110 to 120 | 70 |
How trotting races are run differently
Start type is the biggest difference. AHRR 142 makes the mobile the default, so a standing start needs the approval of the controlling body or the chairman of stewards. In the July to September 2026 results, 81 of 429 trotting races (18.9%) started from a stand, against 38 of 3,080 pacing races (1.2%). The share depended on the state: Queensland started 30 of its 63 trotting races from a stand, Victoria 17 of its 264.
A standing start usually brings handicaps. Horses start from marks in metres behind the front, and under HRA's handicapping rules an automatic handicap sets 5 rating points at 10 metres. How the two starts work, and how to price a back mark, is covered in mobile vs standing starts.
Fields were a little smaller too: trotting races from the mobile averaged 8.3 starters, pacing races 9.1. HRA's rules also provide for Monté races, trotting races ridden in a saddle, which carry a break rule of their own (below).
How often each gait breaks, and what it costs
A break is a switch from the racing gait into a gallop. Every horse can break, but the July to September 2026 results show how much more often trotters do:
| Measure | Trotting races | Pacing races |
|---|---|---|
| Starters that broke | 605 of 3,572 (16.9%) | 1,227 of 28,061 (4.4%) |
| Races with at least one break | 306 of 429 (71.3%) | 924 of 3,080 (30.0%) |
| Favourites that broke | 64 of 437 (14.6%) | 142 of 3,138 (4.5%) |
| Win rate of horses that broke | 15 of 605 (2.5%) | 41 of 1,227 (3.3%) |
| Win rate of horses that did not | 415 of 2,967 (14.0%) | 3,042 of 26,834 (11.3%) |
These counts come from the stewards' comments HRA prints beside each runner, where "broke" is noted. A break in the score-up of a mobile start counts; a broken gear item does not. A trotter that broke won 2.5 / 14.0 = 0.18 times as often as one that did not, so a break cuts a trotter's chance to under a fifth on average.
Favourites won about as often in both gaits, 41.9% of trotting favourites and 41.1% of pacing favourites, even though trotting favourites broke three times as often. A break costs the horse that makes it, so the risk belongs in each runner's price rather than in a rule about the whole race.
A gallop and your bet
A gallop cancels nothing. AHRR 128(1) makes every horse drawn up behind the barrier a starter, so a trotter that breaks at the start has still run, and a win bet on it needs it to recover and finish first. A ruling at the start can change that, such as a horse declared a non-starter or withdrawn after causing two false starts. Harness racing betting rules sets out each case, and your bookmaker's terms decide how each bet type settles.
Once the race is on, the driver must pull the horse back to its gait at once, without gaining an unfair advantage or interfering with another runner (AHRR 154). If it gains or holds ground while galloping, or interferes, the stewards can disqualify it or place it lower (AHRR 155). In a Monté race, a break clear of interference in the final 200 metres means disqualification (AHRR 331). Breaking stride covers how stewards record a break.
Worked: pricing the break risk on a trotter
Example: Illustrative numbers for a made-up trotter, not a real race or market. You rate Runner 3, a trotter, a 30% chance if it trots cleanly. It broke in 3 of its last 12 starts, so you put today's break risk at 3 / 12 = 25%. If it breaks, you cut its chance to 5%, a little under the 30 x 0.18 = 5.4% that HRA's counts suggest.
chance = (1 - break risk) x clean chance + break risk x chance after a break = 0.75 x 0.30 + 0.25 x 0.05 = 0.225 + 0.0125 = 0.2375
| Ignoring the break risk | Allowing for it | |
|---|---|---|
| Chance | 30.0% | 23.75% |
| Fair price (1 / chance) | 1 / 0.30 = $3.33 | 1 / 0.2375 = $4.21 |
| Value of $10 at $3.70 | 10 x (0.30 x 3.70 - 1) = +$1.10 | 10 x (0.2375 x 3.70 - 1) = -$1.21 |
| Value of $10 at $4.80 | 10 x (0.30 x 4.80 - 1) = +$4.40 | 10 x (0.2375 x 4.80 - 1) = +$1.40 |
Ignore the break and $3.70 looks 11% better than fair. Count it and the same bet loses 12.1 cents in the dollar on average. Three breaks in twelve starts is a small sample, so treat 25% as a rough figure. Look at where each break happened, too: a horse that only breaks in the score-up of a mobile carries a different risk from one that breaks under pressure in the straight.
Risk: Betting involves risk. Your break estimate and your clean-run chance are both guesses, and Runner 3 loses about three races in four even when the price is right. There is no guarantee of profit; see responsible gambling for limits and support.
Hopples and other gear
Hopples are loops round each foreleg and the hind leg on the same side, joined by a strap, so the two legs on a side swing as one and the horse holds its pacing gait. A pacer racing without them is free-legged. Trotters race without pacing hopples, and HRA's approved gear list (checked October 2026) bans cross hopples and half hopples on the back legs of trotters.
Any gear change has to be applied for before the race (AHRR 269), and how to read harness form covers where each meeting's gear changes are posted and what blinds, ear plugs and boots signal.
Mistakes that cost money on the two gaits
- Comparing a trotter's mile rate with a pacer's. The 4.3 seconds a mile between Melton's two records is about 83 m over 2,240 m, so a trotter's time looks slow only against the wrong yardstick.
- Pricing a trotter on its clean-run chance. In the worked example that turned a $3.70 bet worth -$1.21 per $10 into one that looked worth +$1.10.
- Reading a trotter's mobile form into a standing start. Nearly one trotting race in five started from a stand in the July to September 2026 results, and a horse can be sharp from one start and slow from the other.
- Expecting a refund when a horse gallops. A gallop is part of the race, so the bet stands and settles on where the horse finishes.
- Missing a gait change. HRA's handicapping rules adjust a converted horse's rating as though its past races were run at the new gait (rule 10.7), so check what gait a form line was run at.
Checking the price once you have a number
Once your fair price allows for the break risk, the job is finding a price above it. The Terminal shows prices from 40+ bookmakers across racing and sports. On its racing board the trots sit beside thoroughbred and greyhound meetings, a code filter narrows the list, and the best available price on each runner is picked out. B337 does not rate horses or pick runners, so the break estimate stays yours.
Prices are read on a repeating cycle rather than tick by tick, so confirm the price in your bookmaker account before you bet. A free account opens a limited view of the Terminal with live odds. Bookmaker names are trade marks of their owners. B337 is not affiliated with them.
Risk: Betting involves risk. A price above your fair price can still lose, and trotting races add the chance of a gallop to everything else that can go wrong. For free and confidential support call 1800 858 858 or visit gamblinghelponline.org.au. See responsible gambling for limits and support.