[Closed] Ebike rear shock tuning/advice please.

sounds like volume spacers are needed. That'll potentially sort the issues you describe.

What are you classing as 'the correct sag' ?

How fat?

I weighed 115KG when I first got my eeb and I could get the shock on that working ok. It was a bit harsh off the top, but bottom outs were never a problem.

Ok,

So Im 115kgs

I think there is a max pressure limit on the shock of 350psi, I am at about 310psi to get 30% sag.

If I pump it up to 20% sag it feels to harsh.

Currently @ 30% sag the bike blows its mid travel just dropping of a kerb. However, even riding hard I dont think Ive bottomed the shock out as it feels like it ramps up loads at the end.

I think I would like a plusher feeling with more midrange support? Is that possible.

“ sounds like volume spacers are needed. That’ll potentially sort the issues you describe.”

Wrong way around - if it’s blowing through the midstroke and then ramping up too harshly it needs more air pressure and fewer tokens.

A heavier damping tune is needed and a larger volume shock with a bigger negative spring. I’d have a look at the Cane Creek DBair shocks - as a default they’re more damped and calm feeling and you can tune them yourself by twisting knobs. Avoid the Inline version if the shock is driven by a yoke.

A heavier damping tune is needed and a larger volume shock with a bigger negative spring. I’d have a look at the Cane Creek DBair shocks – as a default they’re more damped and calm feeling and you can tune them yourself by twisting knobs. Avoid the Inline version if the shock is driven by a yoke.

Do you mean a yoke as in the link that bolts to the bottom of the shock?

Would it be worth trying a shock tune on the Deluxe shock first or is it better just to go straight to a different shock?

Avoid the Inline version if the shock is driven by a yoke.

Elaborate ?

The CC shocks have a reputation for snapping shafts when used on yoke driven full suss, but I thought that was only the coil.

I'd call TFTuned or similar and ask their advice. They can either advise add/remove volume spacers or even a custom tune. It will cost a few £ but a lot less than a new shock that may have the same issue.

The CC shocks have a reputation for snapping shafts when used on yoke driven full suss, but I thought that was only the coil.

Well i certainly wasn't aware of that one... Thanks for the info fellas.

as per cgg advice - I'd look to remove any volume spacers from the shock air chamber,and try again.

If there are no volume spacers already installed then its probably time for a new shock - unless you can install a larger volume air chamber on the shock you have?

Well i certainly wasn’t aware of that one… Thanks for the info fellas.

Me neither. Good to know !!

I have the same issue with my Rockshox Super Deluxe Select on my Vitus 21 ebike. Though the suspension is extremely sensitive but it blows travel like nobodies business. I'm half tempted to get a coil.

On my other bike (non eeb) the Super Deluxe Ultimate does blow through travel but doesn't feel half as squishy and unsupportive, perhaps its helped by the large amount of anti squat.

There isn't any difference between the ultimate and select other than the fancy dials unless I'm missing something.

Had the same issue on my 5010 when I was at my heaviest (99kg). Smaller volume spacer and more pressure solved it.
A bigger negative chamber may also be useful combined with the above. Can get the Megneg upgrade for your shock for not too much money. Was one for sale in the classifieds this week with spacers (no connection to seller), not sure if it’s the right one though or still there.

A bigger negative chamber may also be useful combined with the above. Can get the Megneg upgrade for your shock for not too much money. Was one for sale in the classifieds this week with spacers (no connection to seller), not sure if it’s the right one though or still there.

I did look into the meg neg but apparently it requires even more air in the shock to start with and as Im getting close to the max air pressure i discounted it.

115kg is heavy, but it's not insanely heavy.. I honestly wouldn't expect you to be up near 350 anyway. Which tells me that something else in the tuning isn't quite right potentially. I am 90kg and run 220. I'd have thought mabye 280-300 for you, but that's still a chunk less than 350.

In some of the reveiws Ive read it says that Whyte spec the shock with a light tune so maybe its to do with that?

In some of the reveiws Ive read it says that Whyte spec the shock with a light tune so maybe its to do with that?

seriously - take the volume spacers out.

seriously – take the volume spacers out

To be honest Im not sure if there are any fitted?

as suggested above, try a meg neg. different bike and rider weight (105kg), but the meg neg made a noticeable difference to the supper deluxe. previously it was harsh and wooden or would blow through the travel - there was no middle ground. fpor £90 it was a relitively cheap experiment that worked well

To be honest Im not sure if there are any fitted?

It looks like on the e150 it has 2 tokens installed by default

as suggested above, try a meg neg. different bike and rider weight (105kg), but the meg neg made a noticeable difference to the supper deluxe. previously it was harsh and wooden or would blow through the travel – there was no middle ground. fpor £90 it was a relitively cheap experiment that worked well

Ive just spoke with TFtuned and the chap said at my weight not to go with a Megneg as they need 30% more air which would put me over the max shock pressure.

I’d still try taking a volume spacer out and upping the pressure. You’re still a good bit away from max. All it will cost is a bit of time.
Don’t get too hung up on the so called light tune. Unless the spring is right changing damping is just papering cracks.
Know anybody with a shockwiz? May give an idea of what is actually going on versus what is going on. Can be hired for a weekend as well fairly cheaply.

As an aside, what rear tyre you running? Reason I ask is my 27.5 e150 came with a double down rear casing which feels completely dead compared to an exo.

Isn't this the bike you are trying to sell.....

Why spend more money on it in that case?

I’d still try taking a volume spacer out and upping the pressure. You’re still a good bit away from max. All it will cost is a bit of time.
Don’t get too hung up on the so called light tune. Unless the spring is right changing damping is just papering cracks.
Know anybody with a shockwiz? May give an idea of what is actually going on versus what is going on. Can be hired for a weekend as well fairly cheaply.

Thanks, going to have a look and see if there are spacers in it tonight.

I had thought about a shockwiz, since upgrading the fork with the charger damper its massively outperforming the rear shock but could still be better itself.

Isn’t this the bike you are trying to sell…..

Why spend more money on it in that case?

I have had it up for sale but keep getting offered silly money for it. Ive also spent a lot on "upgrades" for it so would stand to lose a fair bit of cash.

That plus there is nothing on sale currently that would replace it as everywhere is out of stock.

Isn’t this the bike you are trying to sell…..

Nah can't be it's a well known fact that he keeps his bikes for years and never sells them because something isn't right.

Nah can’t be it’s a well known fact that he keeps his bikes for years and never sells them because something isn’t right.

I was wondering how long it would take for the sarcastic comments.

What does it matter if I've had it up for sale or not?? Genuine question.........

Ive come on asking for advice thats all.

It doesn't.
It's just an observation and a bit of a standing joke how often you swap bikes.
Carry on as you were.
You know deep down keep changing bikes doesn't solve the problem.

I reckon a megneg might really help here. Would increase the mid-stroke support noticeably. They're actually good pieces of kit.

I reckon a megneg might really help here. Would increase the mid-stroke support noticeably. They’re actually good pieces of kit.

I had considered it however after speaking with one of the techs at TFtuned this morning he said it wouldnt be a good idea as when its fitted you need to run more air pressure which would put me over the max shock pressure.

Renton, I can loan you a Shockwiz mate

Renton, I can loan you a Shockwiz mate

That's really generous. I'll ping you a pm.

Thanks.

Steve.

Fair enough you would be close to the max. Did they say a custom tune might help?

I found a shockwizz helpful as it showed how badly my pump gauge was reading, I had way less pressure in there than I thought.

Fat and used to be thin man here. Weigh 113kg nekkid.

Have found that getting air shocks to perform optimally at 100kg+ is so difficult to be almost impossible. My answer to this has been coil. I have two bikes with Ohlins TTX22 coil.

Interestingly, air forks have not given the same hassle.

Try putting a spacer in the negative chamber.

I’ve an e180rs and I find exactly the same as you. Need to run 330psi in the x2 to stop it blowing through. Faffing about with spacers doesn’t help either. There’s something fundamentally awry with the design.

Also, unless you run 20% sag it’ll kill pedals with strikes in days. It’s not like the geometry is wrong either, it’s within a gnats chuff of the figures on my alpine & that’s completely fine. It just gets 70 or 80% through travel, gives up support and down it goes, as if the leverage ratio at the end of travel goes up massively. I need to re-ShockWiz it now I’m 6 months into ownership and see what it suggests.

Also, unless you run 20% sag it’ll kill pedals with strikes in days. It’s not like the geometry is wrong either, it’s within a gnats chuff of the figures on my alpine & that’s completely fine. It just gets 70 or 80% through travel, gives up support and down it goes, as if the leverage ratio at the end of travel goes up massively. I need to re-ShockWiz it now I’m 6 months into ownership and see what it suggests.

This is exactly how my rear travel feels. Lots of pressure to get anywhere near correct sage, then blows most of its travel before ramping up massively at the end. Dont think Ive ever bottomed out the shock even at 30% sag??

“ Try putting a spacer in the negative chamber.”

This is a good idea! That’ll firm it up at the start of the stroke. Take out some volume spacers to soften the end of the stroke. And then up the air pressure to firm the middle of the stroke.

If that gets you roughly in the right place then a custom tune with more low speed compression should finish the job.

fwiw, I'm 96kg on a Commencal Meta Power, which has a similar shock arrangement (150mm travel, 210x55 rockshox super deluxe ultimate) and I run 245psi to get just under 30% sag. Shock doesn't seem to blow through its travel. Certainly not dropping off a curb. I have to run rebound 2 clicks off max though.

Maybe it came with the wrong shock tune?

Maybe it came with the wrong shock tune?

Going off what other people have said on the Whyte ebike stalkbook page, it's a common complaint (once you get through the fog of bad spelling, flag waiving, massive mudguards and questions like: "its got tu mANy geaz, kan I MAK it 8 spead!?!!")

“ Try putting a spacer in the negative chamber.”

This is a good idea! That’ll firm it up at the start of the stroke. Take out some volume spacers to soften the end of the stroke. And then up the air pressure to firm the middle of the stroke.

Is this an option? Ive seen nowhere on the net mention neg air volume spacers??

Yeah you can put spacers in the big negative chamber. That's kind of the point to be able to tune the negative spring as well as positive.

from J-tech a few years back, when I was having similar issues (you use the same 'band' spacers):

Yeah you can put spacers in the big negative chamber. That’s kind of the point to be able to tune the negative spring as well as positive.

Do you have a link at all showing how its done?