ESA - off road settings

[spm0912]

My ESA works fine, press the buttons and bike goes up and down, goes soft and stiffens and generally performs well.

But can anyone tell me what actually happens to the suspension when you put it into off road mode? I know in high mountain it raises both the front and rear of the bike but is that it, just the ride height to give more ground clearance, or is there more trickery going on? On the road it feels a bit harsher, altered spring rate maybe? Or just my imagination?

Reason I ask is the bikes been lowered by Revs, mainly for when I'm 2 up and loaded with 2 weeks worth of excess baggage, flying solo the original ride height never really bothered me and there are times I'd like the extra ground clearance, ESA in high mountain pretty much returns the bike to standard height. So anyone actually know, rather than guess?

 

[tanneman]

The suspension is a bit softer too.

 

[Bendy toy]

ESA can't change spring rate
Low Mountain uses the standard comfort damping rate. High Mountain is taller still with absolute minimum damping.
I like it for the most narrow back lanes in Devon even if reaching the floor is challenging.
PS I wonder how the new Wilbers WESA for standard bikes compares to BMW ESA.
Booger I now can't find the link.

 

[Alan R]

ESA can't change spring rate.

ESA changes the spring pre load by operating a hydraulic collar which presses down on the spring: hence the change in ride height.
Alan R

 

[robb]

PS I wonder how the new Wilbers WESA for standard bikes compares to BMW ESA.

Getting mine done next week but it will be a new Wilbers vs 27k miles BMW esa comparison. Bit like new tyres vs old I expect. Have to see if I'm any quicker round Cadwell the week after

 

[spm0912]

ESA changes the spring pre load by operating a hydraulic collar which presses down on the spring: hence the change in ride height.
Alan R

Thanks, yep I get that, but by compressing the spring will that not change the characteristics making the spring harsher as there is less travel ( what I'm finding) or does it make no difference apart from altering ride height?

 

[Alan R]

Thanks, yep I get that, but by compressing the spring will that not change the characteristics making the spring harsher as there is less travel ( what I'm finding) or does it make no difference apart from altering ride height?

As Bendy suggests, the spring rate is not changed but, the spring being under pre loaded compression, makes the ride firmer as some of the 'springiness' has already been taken up. I don't pretend to have a degree in suspension technology, but these are my observations and reasoning from playing with bikes for many years.
Alan R

 

[Bendy toy]

I think the preload just raises the ride height. But when the shock reaches its limit (no sag), compressing the spring might make it feel stiffer as its now pushing back more than before.
Sag is how much the suspension dips when bike rolls off the centre stand.
Sadly I can't afford a Wilbers WESA buts its top of the list for when I can.

 

[Alan R]

I think the preload just raises the ride height.

No it doesn't. I do have wesa units fitted both fore and aft.
Alan R

 

[Pukmeister]

Getting mine done next week but it will be a new Wilbers vs 27k miles BMW esa comparison. Bit like new tyres vs old I expect.

It's better than that as your spring rates will be bespoke to you and not generic.

Had Wilbers on my '04 wish I could afford them for my GSA.

 

[tanneman]

Did these bikes have the ESA or ESA 2? There is a difference in the adjustment of the suspension between these 2 systems. ESA 2 allows for the adjustment of the spring rate.

Just to clarify. With the mode settings like Comfort, Normal and Sport the rebound damping is adjusted at the front while the rear is adjusted for both rebound and compression. The preload settings does just that. It applies compression on the spring by putting pressure on a piece of elastic bellows above the spring. This raises the ride height or for the more technical the sag is reduced for the same weight on the bike. The difference between the 2 off road settings is the spring preload adjustment. The hilly setting is 50% preload adjustment and the mountain setting is 100% preload adjustment. This is just to ensure the suspension don't bottom out in off road conditions.

Please refer to page 68 and page 93 of your owners manual.

Ideally the suspension should be set for your weight and how you ride. The bike has been lowered for reasons of comfort and confidence. To set it up for your weight you adjust the preload and for how you ride you adjust the rebound and compression. You are absolutely right that the bike would feel harsher as there is less vertical movement with the preload at 100%. I did find that on the mountain setting the bike rolls a bit more front to rear in enthusiastic riding. For a the odd track day the preload setting 2 up with luggage worked best to give a bit more ground clearance and a little bit quicker steering.

 

[Bendy toy]

I find full mountain apart from being taller is also a lot softer. It feels like damping has been turned tight down and ride height right up.
The three normal height damping settings feel like harsh (bounce off bumps) soft (absorb bumps) with an in between (normal). On rough A and B roads I find the bike handles better in comfort mode. Presumably Sport mode is ok for max performance on billiard table smooth roads.

 

[spm0912]

Did these bikes have the ESA or ESA 2? There is a difference in the adjustment of the suspension between these 2 systems. ESA 2 allows for the adjustment of the spring rate.

Just to clarify. With the mode settings like Comfort, Normal and Sport the rebound damping is adjusted at the front while the rear is adjusted for both rebound and compression. The preload settings does just that. It applies compression on the spring by putting pressure on a piece of elastic bellows above the spring. This raises the ride height or for the more technical the sag is reduced for the same weight on the bike. The difference between the 2 off road settings is the spring preload adjustment. The hilly setting is 50% preload adjustment and the mountain setting is 100% preload adjustment. This is just to ensure the suspension don't bottom out in off road conditions.

Please refer to page 68 and page 93 of your owners manual.

Ideally the suspension should be set for your weight and how you ride. The bike has been lowered for reasons of comfort and confidence. To set it up for your weight you adjust the preload and for how you ride you adjust the rebound and compression. You are absolutely right that the bike would feel harsher as there is less vertical movement with the preload at 100%. I did find that on the mountain setting the bike rolls a bit more front to rear in enthusiastic riding. For a the odd track day the preload setting 2 up with luggage worked best to give a bit more ground clearance and a little bit quicker steering.

Pretty much what I thought, thanks. Making progress solo there is bags of clearance when it's in it's normal (lowered) position and with the Wilbers fitted it's very predictable and precise, need the extra height around town and on gravel tracks where the extra preload on the springs will not have a noticeable effect. Best of both worlds? Maybe

 

[Beemerman59]

I have the Wilburs WESA front and rear - I went for a spring equal to my weight at the time I bought them (2 yrs ago). Since then I've lost over 20Kg so the ride is a bit on the firm side even with "Comfort" mode set in single rider mode. I hadn't thought of trying the off road settings - will give these a go next time I'm out.

 

[Bendy toy]

New springs could be fitted to the existing Wilbers shocks.

 

[Beemerman59]

New springs could be fitted to the existing Wilbers shocks.

Sure, I know, but altering the preload to off road maybe a free solution. Or maybe not after a test ride if it's too bouncy!

 

[TunturiSport]

I find full mountain apart from being taller is also a lot softer. It feels like damping has been turned tight down and ride height right up.
The three normal height damping settings feel like harsh (bounce off bumps) soft (absorb bumps) with an in between (normal). On rough A and B roads I find the bike handles better in comfort mode. Presumably Sport mode is ok for max performance on billiard table smooth roads.

I would agree. An increase in preload surely lifts the bike upward and the shock absorber "stretch". As a consequence the compression travel increases and the rebound travel decreases. This would allow softer compression damping but would necessitate more effective rebound damping. I guess (surely do not KNOW) that these changes in damping have been programmed to the system and happen at the same time when we adjust the preload. This guess is supported by my (and Bendy toy's) feeling that the mountain settings feel softer.

 

[Bendy toy]

I suspect any programming of damping rates is pretty basic. But saying that the Wilbers WESA does cover a wider range - read more difference between settings.

I used mine today on full mountains. It rocked fore/aft and floated a bit more than normal but was quicker to ride than in normal height Sport mode, because it wasn't bouncing off the bumps. Only snag was tippy toes at traffic lights.

 

[robb]

Sat in Street Bike waiting for Revs to fit my new WESA units

 

[Deleted account 211025001]

.................. ESA 2 allows for the adjustment of the spring rate.
................................

How so, I'm intrigued ?

Spring Rate is, very simply, how soft or hard the spring is ie how much weight is required to compress the spring a given distance.
Hence, as long as the spring is rated for your weight, increasing/decreasing preload (within reason) has no effect on how soft/harsh the ride is.

Andres



Andres