Join Date: Nov 2010
Location: Harleysville , PA, USA
Re: Newbie ESA question
I stand corrected. The differences between the old ESA and the new are tough to decipher. In 2010, the ESA 2 was introduced. I found the following while on a search and thought I'd share. Sorry if it's not quite on topic.
ESA II Electronic Suspension Adjustment
The BMW R 1200 RT is available with ESA II (Electronic Suspension Adjustment II) already well-known from the K series as an option at extra cost.
Benefitting from this system quite unique in the world motorcycle market, the rider is able to adjust not only the damping on the outbound stroke of the front and rear spring strut, but also the spring base (spring pre-tension) on the front spring strut and the spring rate – all this at the simple touch of a button.
This second-generation Electronic Suspension Adjustment or ESA II for short provides the option to set the suspension for maximum comfort and, with greater precision than ever before, for optimum riding and load conditions, thus ensuring a new dimension of riding stability combined with absolutely excellent response.
To control the Electronic Suspension Adjustment as easily as possible and to prevent any unwanted settings, the rider initially enters the motorcycle’s current load condition (solo, solo with luggage, rider with passenger and luggage).
The appropriate spring base and spring rate is then set automatically, with the system coordinating these two parameters to one another.
Depending on the style of riding he wishes to enjoy, the rider must also choose among the Comfort, Normal or Sport mode, giving the suspension the desired qualities. So applying the optimum parameters kept available in the Central Vehicle Electronics, the electronic “brain” calculates the appropriate damper rates and sets them accordingly.
As a result, the new R 1200 RT benefits from a total of no less than nine different set-up options. With additional adjustment of the spring rate, ride height can be set perfectly to various load conditions, ensuring an even higher standard of riding stability, handling and comfort. Even when carrying high loads with a passenger and lots of luggage, the R 1200 RT maintains all of its riding qualities also when leaning over to a low angle in bends, for a truly sporting style of riding at all times.
A further advantage is that adjustment of the spring rate dramatically reduces the risk of the suspension suddenly sagging under extreme load. The rider is able to change the damper setting (Normal, Sport, Comfort) simply by pressing a button also while riding, while for function and safety reasons the spring base may be changed only at a standstill. The spring rate is adjusted by an electric motor complete with its own transmission, while the damping rate is modified by small step motors on the dampers.
Adjustment of the spring rate is controlled by two springs connected in series, one behind the other. An elastomer unit (Cellasto) in combination with a conventional coil spring further down takes up forces under spring pressure, radial expansion of the Cellasto element to the outside being restricted by a steel sleeve.
On the inside the Cellasto element moves an aluminum sleeve by means of electro-hydraulic connection, the position of this inner sleeve influencing the expansion behavior of the Cellasto element to the inside and, therefore, its spring rate.
In all, this interaction of the various units has the same effect as a combination of two springs varying in strength. Whenever the inner sleeve is resting on the steel spring, the Cellasto unit is not in use and only the steel spring provides the desired suspension effect. Once the inner sleeve is moved further, the spring base on the steel spring – and therefore the spring pre-tension – is also varied accordingly.
This configuration significantly improves the normal static position of the motorcycle and riding geometry under all load conditions, without any of the disadvantages encountered with conventional suspension. Benefiting from this self-levelling, the R 1200 RT is just as stable when riding under full load as it is when carrying only the rider without any luggage.
Additional adjustment of the spring rate over the wide range from 160 – 260 N/mm allows far greater variation of the Sport, Normal and Comfort settings on ESA II than on ESA I, with each set-up providing a far greater choice of specific characteristics.
In other words, the R 1200 RT is even more dynamic and precise in the Sport mode, and very comfortable indeed in the Comfort mode, while maintaining an excellent standard of stability.
In all, ESA II offers the following significant benefits:
Much wider range of settings and suspension options with the Sport/Normal and Comfort modes.
Far better maintenance of the machine’s static, normal position and riding geometry with all settings.
Optimum adjustment of the damping and spring rate / spring base in all settings.
Significant change of the motorcycle’s character through adjustment of the dampers.
Excellent adjustment to all load conditions through the adjustment of the spring rate / spring base.
Significant enhancement of safety when braking and in general riding stability, free side angle in bends and firm suspension without sagging.
2011 R1200RT (sold)