Entire guide to… the history of the Isle of Man TT

It’s the oldest and most demanding motorcycle race in the world. With over 115 years of history, you could write a book about the Isle of Man TT Races (in fact many have) but if you just want some pub ammo to amaze your mates, we’ve got 10 full on facts that are sure to impress.

It’s on the island for a reason…

Motor racing began on the Isle of Man in 1904, when the Gordon Bennett trial (for cars) took place. The Isle of Man was chosen because a 20mph speed limit was in place on British roads and competition was banned. By having its own Government, the Isle of Man was able to give permission for the endurance event and a tradition for motorsport was born.

In 1905, the Gordon Bennett Eliminating Trial also included a motorcycle event and the first Isle of Man TT races took place in 1907. The rest, as they say, is history.

It holds a place in history…

… as the first ever motorcycle Grands Prix were held on the Isle of Man. The 1949 TT was part of the newly formed motorcycle world championships (which went on to become MotoGP), with Harold Daniell claiming the honour of winning the first 500cc Grand Prix on a Norton.

He completed a staggering seven laps of the Mountain course at an average of almost 87mph, in a race lasting over four times longer than a modern MotoGP. The TT hosted the British Grand Prix until 1976, when it moved to Silverstone.

No one really knows exactly how many corners the course has…

…even the Isle of Man TT organisers, whose website lists the number of corners as ‘over 200’. There are 60 named corners on the course but the nature of the circuit, with more gentle curves than sharp bends, means in some cases it’s difficult to even define what is or isn’t a corner. Some place the number as high as 264. Either way, it’s a heck of a lot for the racers to memorise and master – that’s why it takes years for the top racers to come even close to mastering the track.

It's a race of endurance…

At 37.73 miles the TT course is the longest in motorcycling and, for the Superbike and Senior TTs, the race is six laps long. That’s the same distance as at least three MotoGP races, and requires two pit stops for fuel and tyres. The longest race was in 1957, when

Gilera-mounted Scotsman Bob McIntyre won the Senior TT at an average speed of 98.99mph. The eight-lap race marked the longest ever Grand Prix, at just over 300 miles.

It wasn’t always held on the Mountain course…

Although we’re all familiar with the iconic 37.73-mile Mountain course used today, a number of different circuits have been in use on the Isle of Man over the years.

The first race was held on 28 May 1907 and took in 10 laps of the St. John Short Course, a 15.85 mile circuit which started in the village of St. John. The first iteration of the Mountain course we know today came in 1911. The very first section was remodelled in 1915 and although there have been changes over the years, it’s this course which we love today.

That’s not all though. The 10.79-mile Clypse course hosted smaller capacity Grand Prix races between 1954 and 1959. The course took in parts of the Mountain course, but the races were held in a traditional mass start format rather than the TT’s usual time trial.

Although not used for the TT, the Billown circuit is a 4.25 mile roads circuit based around Castletown in the south of the island. This hosts the Southern 100 road races in July, as well as some pre-TT events. Jurby airfield also hosts motorbike races occasionally too.

It’s the oldest motorcycle race in the world…

The Senior TT is the oldest (and most prestigious) race in the world. It first took place in 1909, when it replaced the previous Twin TT which had been held at the first two events.

As well as the Senior, there have been numerous categories for bikes of different types and capacities, including Ultra Lightweights (initially 175cc and then 125cc), Junior (traditionally 350cc two-strokes before becoming 600cc four-strokes) and Sidecars (of various capacities over the years and now generally 600cc four-cylinders).

The Supertwins, as featured in the Entire Cover Supertwin TT, is an evolution of the Lightweight category, which was traditionally for 250cc two-stroke Grand Prix bikes.

TT doesn’t stand for Time Trial…

It’s easy to think that TT stands for ‘Time Trial’ – especially as the race is an, erm, time trial, but it doesn’t.

TT stands for Tourist Trophy, which goes back to the pioneering days of motorsport when events were as much about proving the endurance of these new ‘touring’ machines as much as they were about demonstrating outright speed.

Dunlop dominance

Most people know Michael Dunlop is the winningest rider at the TT, when he surpassed his uncle Joey at the 2024 event. Mickey D has a total of 29 victories ahead of the 2025 edition, with Joey on 26. John McGuinness is third in the all-time list, with 23, while the rider with the most wins from outside the British Isles is Kiwi Bruce Anstey, who has won 12 times. Giacomo Agostini, statistically the greatest Grand Prix rider of all time, took 10 of his 122 GP wins on the Isle of Man.

First 100mph lap and the never ending quest for speed

We mentioned him already as the man who won the longest ever Grand Prix but, in that same race, Bob McIntyre also took the honour of being the first rider to lap the Mountain course at an average speed of over 100mph.

It took 50 years but in 1957, the golden anniversary of the TT, Bob Mac broke the highly anticipated 100mph barrier for the first time. He did so on four of that year’s Senior TT’s eight laps, gunning his Gilera to a best of 101.12mph on lap four. Michael Dunlop paid tribute to the lap 60 years later, donning period riding gear and lapping the course on a replica of McIntyre’s Gilera in a demonstration run.

Moving the goalposts is always an aim for the top TT riders and every breaking of the lap record is much celebrated. John Williams became the first rider to break 110mph, in 1976, while Steve Hislop broke through the 120mph barrier in 1989. John McGuinness was the 130mph master, in 2007, and today the record is held by Peter Hickman, who stopped the clock at 16 minutes, 36.115 seconds on his BMW M 1000 RR during the 2023 Superstock TT for an average of 136.358mph.

Will the 140mph barrier ever be cracked? History suggests the record goes up by 10mph every 20 or so years, meaning we’ve still got quite a few years to wait to see if someone can lop 26 seconds off Hicky’s best and write their place in the history books as the first rider to average 140mph.

The Entire Cover Supertwin TT is our favourite race!

Ok, so we are (very) biassed, but we just love the Supertwin TTs – not just because we’re the sponsor but because the bikes are really, really trick.

Most supertwin bikes start out as humble everyday machines – think Kawasaki Z650 and Yamaha MT-07 – which are then modified using the most liberal set of rules in the TT races. The bikes are highly tuned and the best deliver around 100bhp.

They go up against tackle like the Aprilia RS 660 and the exclusive Paton S1-R (with a 650cc Kawasaki Z650 engine at its heart), which come out of the crate to a higher spec but then receive less modifications, and from there it becomes a riot as teams look to develop the best possible bike for their pilots.

Supertwins are races where reliability and looking after the bike is as important a strategy as going as fast as possible. They’re usually the most unpredictable races of TT week, although Michael Dunlop’s record in the class (he’s won five of the last seven, having broken down in the other two) means he starts as a big favourite.