Dynamic ESA

[CPJS]

Does anyone out there know exactly how the system works?
I would like to know what the device between the subframe and swingarm (potentiometer)? measures .
Is its function just that for measuring ride height or does it influence the damping rates as well.
I would like to upgrade the suspension on my '17 GS TE, at the moment the after market suspension suppliers are lagging behind and as far as I can tell no one has yet got to grips with the Dynamic ESA.
HELP!
Touratech, Ohlins,wilburs etc etc don't cover march '17 onwards.

 

[Deleted account 191119001]

My first question would be, having the same year bike, would be, is it software related, or actually physical change, that is all my small brain could answer at the moment, will be an interesting thread, and good luck if you can do this, will be really nice to have another option for later...

 

[ChazzyB]

I assumed it does both measuring velocity of impacts to adjust the damping and since 2017 auto ride height too.

 

[Deleted account 191119001]

I assumed it does both measuring velocity of impacts to adjust the damping and since 2017 auto ride height too.

That might be the clue as to why Touratech cannot do it, so it has to be something that BMW are not sharing with 3rd parties.

 

[CPJS]

I assumed it does both measuring velocity of impacts to adjust the damping and since 2017 auto ride height too.

The device was not on the GS before march '17

 

[knutk]

The device was not on the GS before march '17

If "The device" means the level sensor, this has been installed on the LC GS all along. Even the first LC 1200 where equipped with optional dynamic suspension. However, the Auto level feature was introduced later. The latest system is way more advanced than generation #1.

 

[fred_jb]

If "The device" means the level sensor, this has been installed on the LC GS all along. Even the first LC 1200 where equipped with optional dynamic suspension. However, the Auto level feature was introduced later. The latest system is way more advanced than generation #1.

More advanced in some respects, especially the auto preload adjustment which I find invaluable, and I think really contributes to retaining good handling qualities even when loaded with pillion and luggage.

However an early version actually had a more advanced, though not completely automatic, way of adjusting for load. This was able to adjust both spring preload (referred to by BMW as "spring base") but could also adjust spring rate through a clever system combining two separate spring elements - a rubber one with adjustable spring rate, and the normal metal spring with fixed spring rate.

I got quite excited when I first read the following linked article, thinking that my GS had this system, but on further investigation and discussion on this forum, it seems that only the early K series bikes had this.

https://www.bmw-motorrad.co.uk/en/experience/engineering/comfort-ergonomics/esa-esatwo.html

 

[CPJS]

If "The device" means the level sensor, this has been installed on the LC GS all along. Even the first LC 1200 where equipped with optional dynamic suspension. However, the Auto level feature was introduced later. The latest system is way more advanced than generation #1.

I am refering to the link rod attached to the swing arm connected to a small arm that goes into a box of tricks next to the top of the shcock, I don't recall seeing one on my '14 GS TE.

 

[ChazzyB]

I am refering to the link rod attached to the swing arm connected to a small arm that goes into a box of tricks next to the top of the shcock, I don't recall seeing one on my '14 GS TE.

So am I and my 2015 GS TE definitely was so equipped.

 

[CPJS]

I don't know how i missed that, I have always got up close and personal when cleaning, anyway..............
I was thinking of fitting a slightly stronger spring and was wondering how that might affect the damping function of the ESA.

 

[knutk]

Back to post #1. Op asks two questions:
-- 1: What are the input from the sensor arms used for.
-- 2: Any 3 part suppliers out there that may use this information.

#1: seems to be covered already.

#2: Touratech now offers their 'DDA / Plug & Travel SUSPENSION-SET' to be used on all LC GS/GSA, including the 1250.


Does this make sense?

Yes, indeed.

The 'Brains' of the system is to be found in the computers and software.

The suspension is basically modified regular dampers.

On a descent damper you regulate preload with a hand operated handle that regulates a hydraulic piston. The damping is adjusted by screws that merely controls the flow of the internal damping-oil.

The ESA damper merely replace the Preload regulator with a DC motor and a potmeter for feedback, while the two damping controls (for bound and rebound) are small steppermotors that rotates the regulator valves.


Stepper motor: This is a DC motor that is pulsed, and each puls rotates the shaft a given angel (set by the design). So rotating the shaft, say 180 degrees, is merely to send the motor a given number of pulses. Advantage: Compact and very accurate control of position of the saft. Cons: Not very powerful.

Thus, the heavy load for the preload is handled by a regular DC motor, and the position of shaft needs feedback from a potmeter.


So.. The electric internals of the ESA dampers are merely basic electric control.
Anyone who cares to bother can build an ESA adaptable damper by adapting quality dampers with the proper motors and potmeter for the feedback.
The Dynamic ESA is an evolution of the 1 generation of the ESA. The 1 gen ESA only changed adjustments when the rider hit the buttons, while the Dynamic ESA keeps adjusting, based on feedback from the sensors on the swingarms front and rear. I would expect the motors to be reinforced accordingly.

Bottom line:
If you want improved damping control and maintain the Dynamic control you may do so. But it is not for free….

 

[fred_jb]

Back to post #1. Op asks two questions:
-- 1: What are the input from the sensor arms used for.
-- 2: Any 3 part suppliers out there that may use this information.

#1: seems to be covered already.

#2: Touratech now offers their 'DDA / Plug & Travel SUSPENSION-SET' to be used on all LC GS/GSA, including the 1250.


Does this make sense?

Yes, indeed.

The 'Brains' of the system is to be found in the computers and software.

The suspension is basically modified regular dampers.

On a descent damper you regulate preload with a hand operated handle that regulates a hydraulic piston. The damping is adjusted by screws that merely controls the flow of the internal damping-oil.

The ESA damper merely replace the Preload regulator with a DC motor and a potmeter for feedback, while the two damping controls (for bound and rebound) are small steppermotors that rotates the regulator valves.


Stepper motor: This is a DC motor that is pulsed, and each puls rotates the shaft a given angel (set by the design). So rotating the shaft, say 180 degrees, is merely to send the motor a given number of pulses. Advantage: Compact and very accurate control of position of the saft. Cons: Not very powerful.

Thus, the heavy load for the preload is handled by a regular DC motor, and the position of shaft needs feedback from a potmeter.


So.. The electric internals of the ESA dampers are merely basic electric control.
Anyone who cares to bother can build an ESA adaptable damper by adapting quality dampers with the proper motors and potmeter for the feedback.
The Dynamic ESA is an evolution of the 1 generation of the ESA. The 1 gen ESA only changed adjustments when the rider hit the buttons, while the Dynamic ESA keeps adjusting, based on feedback from the sensors on the swingarms front and rear. I would expect the motors to be reinforced accordingly.

Bottom line:
If you want improved damping control and maintain the Dynamic control you may do so. But it is not for free….

I believe a motor is used to adjust the preload because this does not have to be varied rapidly, just checked and adjusted at the start of each journey.

However, I believe this explanation is an over-simplification with respect to damping adjustments. Using stepper motors to automate the turning of a screw based adjuster to regulate damping oil flow would be far too slow to give the rapid adjustment needed to respond to changing conditions in real time. It appears that the solution actually used is solenoid controlled valves, the degree of opening of which can be regulated very quickly and accurately by electronic control of the solenoid.

The following gives a useful explanation, including mention of fact that the GS has height sensors both front and rear to give improved information about ride attitude to the bike's computers.

https://www.cycleworld.com/2013/03/14/bmw-dynamic-electronic-suspension-adjustment-explained

Fred

 

[Deleted account 191119001]

Touratech now offers their 'DDA / Plug & Travel SUSPENSION-SET' to be used on all LC GS/GSA, including the 1250.

Perfect a few weeks ago only bikes pre 2017 where supported, it aint cheap but in a few years, will still be cheaper than a new bike.....

https://shop.touratech.de/touratech...set-for-bmw-r1200gs-lc-r1250gs-from-2013.html


https://shop.touratech.de/media/manuals/09-045-5885-0.pdf

 

[knutk]

I believe a motor is used to adjust the preload because this does not have to be varied rapidly, just checked and adjusted at the start of each journey.

However, I believe this explanation is an over-simplification with respect to damping adjustments. Using stepper motors to automate the turning of a screw based adjuster to regulate damping oil flow would be far too slow to give the rapid adjustment needed to respond to changing conditions in real time. It appears that the solution actually used is solenoid controlled valves, the degree of opening of which can be regulated very quickly and accurately by electronic control of the solenoid.

The following gives a useful explanation, including mention of fact that the GS has height sensors both front and rear to give improved information about ride attitude to the bike's computers.

https://www.cycleworld.com/2013/03/14/bmw-dynamic-electronic-suspension-adjustment-explained

Fred

Thank you for updated information.

On my K-model, the front damper control cable needed repair, and it contained more than two wires. But this was ESA I, and using solenoids for rapid adjustments rather than stepper motors makes sense when the need rises from merely keeping a fixed value until next adjustment is selected by the rider(as was the case for ESA I and II).

I learn something every day

 

[knutk]

A friend of mine have the TT dampers installed. (-16 GSA)
According to his evaluation. he said that riding on regular roads made very little difference. However, riding on the bumpy stuff, where the regular suspension will bottom out is where the upgraded dampers makes the difference.

 

[Deleted account 191119001]

A friend of mine have the TT dampers installed. (-16 GSA)
According to his evaluation. he said that riding on regular roads made very little difference. However, riding on the bumpy stuff, where the regular suspension will bottom out is where the upgraded dampers makes the difference.

Must agree on that, but the main thing is out of the box they are setup for a 100kg and the sachs are only 80kg, and you can ask Touratech even more if you feel the need, many on here, given the stuff they carry..........