Sinking rear suspension under hard acceleration

[StewMcGrew]

I was out on a training course with Rapid Training yesterday and the instructor noticed that my rear suspension was sinking quite a lot under hard acceleration.

I have noticed this previously as the front wheel becomes very light when accelerating hard.

Now, I do weigh 120Kg. Is this just a spring upgrade issue? something else?

The bike is a R1250GSA TE with the D-ESA system. Can someone explain how the "auto" setting works?

Thanks

 

[Edmund Kean]

I was out on a training course with Rapid Training yesterday and the instructor noticed that my rear suspension was sinking quite a lot under hard acceleration.

I have noticed this previously as the front wheel becomes very light when accelerating hard.

Now, I do weigh 120Kg. Is this just a spring upgrade issue? something else?

The bike is a R1250GSA TE with the D-ESA system. Can someone explain how the "auto" setting works?

Thanks

That’s strange, ordinarily under hard acceleration on a non auto shock, I would expect the unit to lengthen thus raising the rear.

 

[Mr Bean]

That’s strange, ordinarily under hard acceleration on a non auto shock, I would expect the unit to lengthen thus raising the rear.

Wouldn't the weight transfer compress the rear?

 

[Pukmeister]

What suspension setting was the ESA in at the time?

Road mode is very soft and wallowy, whereas dynamic is firm/taught.

 

[landmarkjohn]

I would expect the bike to squat down at the back as the front trys to paw the air when giving it full beans.

Time to change suspension settings to suit. As suggested I would try Dynamic next.

 

[Comfy Old Boots]

That’s strange, ordinarily under hard acceleration on a non auto shock, I would expect the unit to lengthen thus raising the rear.

Pardon? Do you live in an alternative universe? Where everything is back to front? Pure daft. You’ve been watching too much stranger things.


Can the OP not just increase the preload to suit?

 

[Edmund Kean]

Pardon? Do you live in an alternative universe? Where everything is back to front? Pure daft. You’ve been watching too much stranger things.


Can the OP not just increase the preload to suit?

Would you mind explaining why it is daft? Surely it’s better to explain than make mildly pejorative remarks about my comment.

 

[RallyeGS]

Would you mind explaining why it is daft? Surely it’s better to explain than make mildly pejorative remarks about my comment.

Standard on here!

 

[widget]

Would you mind explaining why it is daft? Surely it’s better to explain than make mildly pejorative remarks about my comment.

'midly' ?...............you got off lightly.

 

[Edmund Kean]

Got off lightly? So I’m wrong then.

 

[stever1]

That’s strange, ordinarily under hard acceleration on a non auto shock, I would expect the unit to lengthen thus raising the rear.

How could it lengthen when you are putting more weight on it, thus compressing it ?

 

[Edmund Kean]

Because the forces of an accelerating wheel on the pivoted swinging arm might be greater than the weight transference.

 

[Quattroformaggio]

Before this gets too out of hand, the shaft reaction on pre Paralever BeeEmmTroubleyous can lead to the rear end actually rising somewhat under acceleration, so the comment wasn't totally as daft as it first sounds.

 

[Pukmeister]

As the OP is nearly 19 stones or 120Kg so a fairly well built chap we can assume (presumably in just his undercrackers) it may indeed be that a stiffer rear spring would be of some help, especially if you include the likely future additional weight of riding kit, luggage, pillion etc?

Perhaps a chat with Denz0 of this parish could shed light on the OE spring rating and if an 'upgrade' might help?

ESA settings will change preload and damping, but can't cure an undersprung bike.

 

[Edmund Kean]

Before this gets too out of hand, the shaft reaction on pre Paralever BeeEmmTroubleyous can lead to the rear end actually rising somewhat under acceleration, so the comment wasn't totally as daft as it first sounds.

Aargh you’ve spoilt my fun. There was even a hand slapping head emoji which was lovely.

 

[StewMcGrew]

What suspension setting was the ESA in at the time?

Road mode is very soft and wallowy, whereas dynamic is firm/taught.

Dynamic Pro

 

[StewMcGrew]

As the OP is nearly 19 stones or 120Kg so a fairly well built chap we can assume (presumably in just his undercrackers) it may indeed be that a stiffer rear spring would be of some help, especially if you include the likely future additional weight of riding kit, luggage, pillion etc?

Perhaps a chat with Denz0 of this parish could shed light on the OE spring rating and if an 'upgrade' might help?

ESA settings will change preload and damping, but can't cure an undersprung bike.

Thanks.

I've removed the front and rear shocks on a twin cam before, is the job as easy as that? I could then easily get someone to re-spring it I guess

 

[StewMcGrew]

In addition to the original post, I have noticed the bike's rear suspension get softer over the last 7K miles. I guess might be worth checking for weeping too

 

[er-minio]

Now, I do weigh 120Kg. Is this just a spring upgrade issue? something else?

Change your springs. Standard springs would not be ok with that weight.

I am heavy as well and (Ohlins shocks) always replace the springs on my bikes.

 

[Steptoe]

Pardon? Do you live in an alternative universe? Where everything is back to front? Pure daft. You’ve been watching too much stranger things.


Can the OP not just increase the preload to suit?

Have a good long hard think about it before you accuse others of being daft. ......