Last year, spy shots circulated of a heavily disguised BMW GS model on test. That it was going to be a new model was clear, but quite what the specifications would be was not known. Now, a listing on a BMW Service Request website shows not one but three new GS models.

New BMW GS Models on the Way

It is no surprise that BMW is working on a revised GS model: the GS is BMW's best-selling model and the engineers will be working day and night to ensure it stays that way not only in the BMW catalogue but also against its rivals from KTM, Triumph, et al.

Last summer spy shots emerged of just such a new model being tested. It was heavily disguised as you would expect, but one interesting feature were the shrouds on the cylinders. As these would severely hamper air-cooling of the cylinders, it could only be deduced that full liquid-cooling was being employed for the first time. The presence of larger radiators bore out that assumption.

So far, so good. Now, however, more evidence has come to light from BMW itself. The eagle-eyed snoopers at motorcycle.com have noticed that an online service request form has not one but three GS models listed. The drop-down menu isn't functional at present but lists dozens of models going back years.

Hidden in plain view in the list are an R1300 GS, R1400GS and M1400GS. Now, we kind of knew that an M1300 GS was on the cards after BMW filed trademark applications for the name. Extrapolating from that, an R1300 GS was logical, but where the '1400' bit has come from is a bit of a mystery.

There might be one explanation, however. If we look at the F750 and F850 models, they are powered by the same 853cc engine. Could that be the case with the R1300 and R1400 GS models?

It is also notable that there is no mention of 'Adventure' versions of the new models. That could be simply that they have not been scheduled for release just yet. BMW normally only launches the Adventure models a year or so after the 'standard' models. Or it could be that the 'Adventure' name will be dropped and the '1400' models will become the larger-tanked and fully off-road-equipped models.

Whichever way BMW is going, it is certain they are not moving away from the boxer twin engine for its flagship adventure bike. Despite telling us that the layout could not be stretched much more than 1200cc without completely re-designing the crankshaft, incorporating a central bearing, which would make the offset of the two cylinders too extreme. And yet, here we are with not only the 1250 but potentially a 1300 or even 1400.

It will be very interesting to see what they have done.