Adjusting the lockring on the Ohlin STX46 shock. Help!

[sk8norcal]

Help! Tried to adjust the preload on my Ohlin STX46, but failed.  
I loosened the top lockring, but the lower lockring is hard to turn due to the spring under compression.
 

Any tips on turning the lockring on my Ohlin shock? Space it tight and my friend's wrench kept slipping. I think I need a better "Shock Preload Spanner Wrench"
 

Also, what is the ideal rear sag in mm for comfort?
Ohlin manual suggests 30mm
Current rear sag for me at 170 lbs
(R1-R3) = 24mm
I find the current ride too firm on rough roads.
 

Rear spring is 115N/mm = 657 lb/in

Rebound dampening is 14 clicks stock. I have it 18 clicks right now

Front fork is stock.

[stickshift]

With the right (Ohlins) tool it doesn't take too much effort on mine. Use a tool that doesn't slip.

 

I would aim for the 30mm sag that Ohlins suggests. I found rebound at the suggested 14 clicks perfect for my weight (160lb).

[YZEtc]

I agree with the above:

With the correct wrench made to adjust the preload, it is no big deal.

I'd buy a genuine Ohlins wrench, myself.

[rick]

Hooks at both ends so you don't have to flip the wrench. It really is the right tool for the job  https://www.ebay.com/i/192283194870?chn=ps

 

You can also give that junction between the spring and collar a wee bit of oil. 

[sk8norcal]

ok, I will get a better tool.

I have read that some people think the stock tool is not that great either....

 

this might work too, no?

 

 

[no-lag]

any local motorcycle shop can get this tool. I sell them here for 30$ arrive next day.

[mjh937]

1 hour ago, sk8norcal said:

ok, I will get a better tool.

I have read that some people think the stock tool is not that great either....

 

this might work too, no?

 

 

That seems like overkill and a lot more work.  Try the correct wrench first, it should not be too difficult. 

[no-lag]

this is what i use.

 

[rick]

11 minutes ago, no-lag said:

this is what i use.

 

and that's exactly the spanner in the link I posted above 

 

as for $30? Seriously? 

[no-lag]

4 minutes ago, rick said:

and that's exactly the spanner in the link I posted above 

 

as for $30? Seriously? 

yes Rick, I am a motorcycle repair shop here in Canada.

 

so everything i post is most likely in $CAD not $USD

 

also that is right from Ohlins, not Chines made.

[rick]

1 hour ago, sk8norcal said:

ok, I will get a better tool.

I have read that some people think the stock tool is not that great either....

 

this might work too, no?

 

 

Spring compressors are handy for when you want to remove the spring from the shock.

 

I'm hesitant to say NO ONE uses one of these just to adjust preload, cause there's always one nut out there. - but. 

[rick]

Just now, no-lag said:

yes Rick, I am a motorcycle repair shop here in Canada.

Oh, Canada - sorry. Shipping from there is always crazy expensive. 

 

The going rate here - at least for now  - is, well, less

 

 

[pattonme]

16 hours ago, sk8norcal said:

Also, what is the ideal rear sag in mm for comfort?

There is no such thing. Provided you're not topped out, 1/2" of preload or 2" of preload doesn't change the "stiffness" of the shock. It's still 115N/mm. Tool is available from Amazon and Ebay for $14'ish. Buy 2. They work on a lot of different shocks.

[sk8norcal]

14 hours ago, pattonme said:

There is no such thing. Provided you're not topped out, 1/2" of preload or 2" of preload doesn't change the "stiffness" of the shock. It's still 115N/mm. Tool is available from Amazon and Ebay for $14'ish. Buy 2. They work on a lot of different shocks.

 

Thanks, ordered the tools off amazon..

 

maybe I am not fully understading the preload.    (sry, new rider here)
I understand the spring rate is linear, but doesn't it take more bump force to compress the spring?

 

at 1:15 mark,  "the more preload you put on the spring, the stiffer it will feel"

 

[blackout]

10 hours ago, sk8norcal said:

 

Thanks, ordered the tools off amazon..

 

maybe I am not fully understading the preload.    (sry, new rider here)
I understand the spring rate is linear, but doesn't it take more bump force to compress the spring?

 

at 1:15 mark,  "the more preload you put on the spring, the stiffer it will feel"

 

You are correct.  A 675 lb/in spring will need 675 lbs to compress the spring one inch and 1,350 lbs to compress two inches.

 

I would shoot for 1.5" of sag for comfort, maybe even as much as 1.75".

[blackout]

On ‎7‎/‎9‎/‎2018 at 10:28 AM, sk8norcal said:

ok, I will get a better tool.

I have read that some people think the stock tool is not that great either....

 

this might work too, no?

 

 

When I switched to a softer spring, I tried a similar tool to compress the spring to remove the hat on my Nitron shock.   It did not work well for me at all.  I had to do it this way.  There is a hole in the aluminum plate just large enough for the spring hat to fit through, but small enough that the plate engages the spring.  Not saying to adjust preload this way, just showing that compressing the spring is not an easy task with flimsy tools....  With that being said, it is quite possible that your shock spring preload was set like shown below at the factory, and that might be why it's so hard to turn the collar as there is descent preload on the spring.  Sorry for talking in circles...

[sk8norcal]

I got the right tool off amazon,

ohlins shock spanner wrench

https://www.amazon.com/gp/product/B00415XAH0/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1

 

"C-spanner wrench allows you to adjust spring preload on Ohlins S46 shock absorbers"

quality looks great to me.

 

It was easy with the correct tool.

also, doing it on the left side of the bike  gives more clearance.

 

 

 

[sk8norcal]

ok,  I adjusted the sag 

 

R1-R2 6mm
R1-R3 30mm

which matches what's recommended in the owner's manual.

 

rebound dampening at 19 clicks (14 clicks is stock)

 

It rides less harsh now.  but still too firm on some of the bumpy roads around here.

 

Gonna add more sag and experiment.

 

 

[sk8norcal]

Added more sag, even better!!

 

Rides beautiful now.  Shock eating up all those bumps.  It was beating me up before. LOL

 

Gonna do the fork oil mod next....

I think the stock spring is okay for my weight (170 lbs without gear)

[sk8norcal]

On 7/9/2018 at 2:58 PM, pattonme said:

There is no such thing. Provided you're not topped out, 1/2" of preload or 2" of preload doesn't change the "stiffness" of the shock. It's still 115N/mm. 

 

Pattonme, so why did my ride  felt softer after increasing rider sag?

 

I saw in another post where you said,

"more preload makes the shock stiffer so it will move less given the same bump impact"

 

still trying to under this....

[pattonme]

really, I said that? Can you point to the message so I can go fix it? A constant-rate spring is always constant until either coil-bind or the suspension is topped out.

[sk8norcal]

35 minutes ago, pattonme said:

really, I said that? Can you point to the message so I can go fix it? A constant-rate spring is always constant until either coil-bind or the suspension is topped out.

^ it should be on the first page.

So, why dd my ride improved after decreasing preload?

[twf]

Because you have more travel on extension. 

[sk8norcal]

http://www.promecha.com.au/myths_misconceptions.htm

 

 

More Preload makes the spring stiffer?

 

   

Preload makes the bike sit higher, or lower - it does NOT make the spring stiffer. 

   

 "So if someone tells you that you should reduce your preload to make the bike feel less harsh, they probably don’t have a clue" (GB). A spring's job is to be able to compress almost fully and then return to it's free length without any changes to length or rate. When you "preload" a spring it simply means you compress the spring with a load or adjuster before any vehicle/bike load is put on the spring. So if you have a spring that has a rate of 1Nm per mm and when you assemble the forks you compress the spring (preload) 10mm with the adjuster backed right off, then that is "fitted preload". The usual preload adjuster has a further 15mm of preload range, this means the total force you have stored in the spring is 25Nm. To make the fork move you have to exceed this load, and then the rate increases by 1Nm because that's the spring rate. What makes it feel more stiff is that instead of starting at 10Nm it starts at 25Nm because the one force is higher than the other. This is what gives you the feeling of a stiffer spring.

[blackout]

While the spring is not stiffer measured in lbs per inch when adding preload, it will require higher forces to compress the spring a given amount when it is preloaded more by the shock collar.   Explaining this is tricky, but just know too much preload and too little sag will cause a harsher ride.