THE BMW GS has just become the longest-running model in modern motorcycling, clocking up 30 years of continuous production.

The Bavarian manufacturer may not have invented the dual-sport category in September 1980 when it launched the first in a long line of GS models, but it certainly popularised it.

Thirty years on, the GS is the world's best selling big capacity motorcycle.

But the R80G/S was the world's first big adventure motorcycle as we call the category nowadays.

The suffix stands for Gelande/Strass, that's off-road/on-road in German, with the slash dropped in 1988 to become GS.

BMW launched the bike to stave off the threat from the Japanese who were building all types of motorcycle for all budgets, capturing the lion's share of a booming market.

It needed an exciting new model to freshen up its conservative line-up - work had started on its innovative range of K-series three and four cylinder engines, but these were still four years away.

BMW also hoped to regain its competitive edge in sporting events with the G/S - a wish it more than fulfilled.

In 1983 the bike won BMW's first Paris-Dakar in the hands of Hubert Auriol. BMW went on to dominate this most high profile of desert races in the 80s, the big capacity G/S winning again 1984 and 1985 with Belgian rider Gaston Rahier.

The Paris-Dakar winning machines were highly modified, yet the standard bike was still hugely capable off-road.

Most big trailies today have no real off-road credentials and their owners have no interest in taken them off the beaten track; they simply enjoy the supremely comfortable riding experience wrapped in the manly adventurer image.

But the GS wasn't built for posing - it's the world's most versatile motorcycle that will take you anywhere, whether it's to work, to Tesco or to Timbuktu and back again showing you a great time along the way.

Just ask Helge Pedersen. The adventurer set off from Norway on an R80G/S named Olga in 1982 to see the world.His two-wheeled adventure lasted ten years.

He crossed treacherous terrain to reach the world's most remote areas, covering 75 countries and 217,000 miles on that same bulletproof machine. The bike now resides in the BMW museum in Munich while Helge heads up adventure touring company, GlobeRiders LLC, on his latest GS.

This go-anywhere potential and Paris-Dakar image persist today (long after rule changes stopped the use of the big capacity GS in the glamorous desert race), and continue to make the GS such a success.

A best-seller in many countries including, unsurprisingly, BMW's home turf Germany.

But it's also Italy's best-selling motorcycle. With home grown manufacturers including Ducati and Aprilia building beautiful and fast motorcycles it appears the Italians would still rather ride the weird-looking BMW GS with its oddball engineering.

Even in the UK, the land of the sports bike enthusiast where off-road machines have traditionally sold badly, the GS is a regular in the top three bestsellers, and was the country's best selling big capacity motorcycle in 2006 if you count the R1200GS and GS Adventure as a single model - selling a staggering 2,277 bikes.

Of course, it was helped along the way by the UK's BBC prime time television series The Long Way Round that was beamed into millions of UK households in 2004, further glamorising the GS and proving it's as happy on the congested roads of Britain as on the desolate tracks of Africa.

KTM must still be kicking itself for turning its nose up at that gig.

But the series also came at the right time, capturing the mood of UK bikers who were shifting away from head-down, bum-up, licence-threatening sports bikes towards more practical machines that were equally as cool but for different reasons, such as naked bikes... and adventure motorcycles.

To mark 30 years of GS, BMW released 2010 special editions of the R1200GS and R1200GS Adventure, finished in the former BMW Motorrad Motorsport colours of Alpine White with three-colour decals and a selection of extras.

With their basic spec, the R1200GS and Adventure cost £10,350 and £11,350 respectively.