Talk to me about sh...
 

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[Closed] Talk to me about shock tuning

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My 2013 Trek Superfly FS has a Rockshox Monarch RL, and I don't particularly like it, purely because if I set it to the amount of sag I want I can only get about 60% of the travel, and even if I set it too soft I never get full travel. It may not be the original shock.

So I would like to know if a) this problem is likely caused by the shock being from a different frame and having a different tune, and b) if this is possible to rectify? I suspect it's an OEM shock so probably doesn't have adjustment options. I've serviced the air can, there doesn't appear to be any tokens in it to remove.


 
Posted : 30/11/2019 8:25 pm
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I'd try speaking to James at Jtech about your wants & needs, he's been my "go to" since Loco left the business, and was highly recommended by Simon (who did some excellent shock tuning for me) himself.


 
Posted : 30/11/2019 8:56 pm
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air shocks are hard to measure the right sag due to the stiction
however, have you tried it with no air, does it get 100% travel?
Id pump it up so i get 100% travel on the biggest stuff.then if you want less sag, you can replace the oil with a thicker one.
assuming that there is no air mixed in with the oil


 
Posted : 30/11/2019 9:07 pm
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I don’t particularly like it, purely because if I set it to the amount of sag I want I can only get about 60% of the travel

What % sag are you setting?
How much are you mincing?
Can you fit a larger air can?


 
Posted : 30/11/2019 9:13 pm
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however, have you tried it with no air, does it get 100% travel?

Almost to the end of the shaft but not quite.

then if you want less sag, you can replace the oil with a thicker one.

That won't reduce sag, it'll just take longer to get there. What you say would work the other way round - pump it up to get the right sag then use a lighter oil to get full travel.

There could be air in the oil plausibly, although I don't hear any squelching sounds.


 
Posted : 30/11/2019 9:14 pm
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I'd borrow a Shockwiz off a friendly forum member and cover insured postage both ways.


 
Posted : 30/11/2019 9:15 pm
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What % sag are you setting?

I'm usually running about 35-40%. It needs a lot of air to reduce that. If I put enough air in to get 30% sag that I'd prefer then it's really hard and I feel the bumps much more.

How much are you mincing?

Well, it's an XC race frame, but it does get airborne and I even do deliberate hard landings to see if I can bottom out the shock but it won't go near the last 20% no matter what, and that's even if I run extra sag. It's as if it only wants to be in the middle of the travel!

Wrong oil weight is a possibility.

I’d borrow a Shockwiz off a friendly forum member

What's a shockwiz going to tell me that I don't already know?


 
Posted : 30/11/2019 9:17 pm
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Have you actually measured the travel you're getting? Many shocks are stop short of the bottom of the shaft intentionally although you are still getting the full number of mms travel.


 
Posted : 30/11/2019 9:24 pm
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If you're setting at 40% sag and any getting 60% at full travel there's something proper wrong with your shock.
Get it sent off and sorted.


 
Posted : 30/11/2019 9:28 pm
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If you’re setting at 40% sag and any getting 60% at full travel there’s something proper wrong with your shock.

No.. I can get full travel if I set to 40% sag. But if I set the sag where I want it, I only get 60% travel. It does move all the way through the travel, just not under the right amount of load!


 
Posted : 30/11/2019 9:56 pm
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It may not be the original shock.

That would be my first port of call tbh. I’d imagine that a suspension service company will have the OEM specs for make, model and year and will be able to compare those for the 2013 Superfly with your shock. This will undoubtedly involve you sending your unit to whoever is your preferred company for the comparison but at least you’ll know where you’re starting from.

Suspension tuning is always best done from a known starting point and then preferably making one change at a time to effectively assess any differences.

HTH


 
Posted : 30/11/2019 10:17 pm
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Don't shocks on bikes come pre-tuned to the frame? I've had the air can off, there's nothing in there that I can see that relates to travel or volume. There could be something in the damper that changes the damping rate maybe? I've serviced shocks before and adjusted the external adjusters but never tuned internals, so I don't know what I'd be looking for inside.


 
Posted : 30/11/2019 11:05 pm
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Don’t shocks on bikes come pre-tuned to the frame? I’ve had the air can off, there’s nothing in there that I can see that relates to travel or volume. There could be something in the damper that changes the damping rate maybe? I’ve serviced shocks before and adjusted the external adjusters but never tuned internals, so I don’t know what I’d be looking for inside.

Yes they do. If you dig into Fox shocks, they have a number of basic tine options based mostly around the damping set-up plus a couple of air-can options, I'd guess RS is pretty much the same. Altering the basic damping would mean either changing internal shims or possibly altering the order they're installed. There also appears to the the option to pressurise the damper, see this thread:

https://forums.mtbr.com/shocks-suspension/i-give-up-ifp-pressure-2013-monarch-rt3-how-do-you-set-948980.html


 
Posted : 01/12/2019 8:58 am
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I need to read up on shims, haven't quite figured out what they are and how they work.


 
Posted : 01/12/2019 5:13 pm
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How long has it been ridden without a full service?

If it's never had a damper service, I wouldn't judge whether it needs tuning based on the current performance.


 
Posted : 01/12/2019 5:18 pm
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Have you thought about dropping the IFP pressure. I had a monarch xx which had a race tune so I dropped the oil level and the ifp pressue from 550 to under 300. Was a lot better but still didn’t like it so I replaced it with manitou Macleod which has been brilliant.


 
Posted : 01/12/2019 5:21 pm
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I need to read up on shims, haven’t quite figured out what they are and how they work.

Is this one of those threads where mol tries to strip something down and it cost him more money and even worse riding time that it would have done if he'd just sent it off for a simple service and tune to his bike/preferences? 😟
If you don't even know what a shim is please just send it off for a service.


 
Posted : 01/12/2019 5:25 pm
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RockShox shocks normally have a blue (compression) and red (rebound) sticker on the air can with the tune on it, eg LL, ML, ML3 etc. So you can copy an OEM shimstack for your frame, or custom build one if you know what you are doing, or buy a custom shimstack from a tuner.

RS are straightforward to service if you just methodically follow the instructions, check the service manual for tools required.

You can change IFP pressure, and IFP volume (to a limited extent) to change how the shock behaves.


 
Posted : 01/12/2019 6:04 pm
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Thanks bigyan

Have you thought about dropping the IFP pressure.

I don't have IFP adjustment on this one - assuming you mean the external piggyback thing?

Is this one of those threads where mol tries to strip something down and it cost him more money and even worse riding time that it would have done if he’d just sent it off for a simple service and tune to his bike/preferences?

When did I do that?

This is one of those threads where I learn about how bike stuff works so I end up saving myself tons in the future.

If you don’t even know what a shim is please just send it off for a service.

So, all those people who do know what a shim is, how did they find out? Why can't I find out? Do you know what one is? Why can't you just explain instead of acting superior? This is a pretty odd thing to say when you think about it.. how would anyone find out anything if we all did this?

EDIT Just googled shim stacks, I've seen those when servicing shocks before I just didn't know that's what it was called. So bugger off you smug git!


 
Posted : 01/12/2019 7:40 pm
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Huh. There IS an IFP, and the valve for it is hidden in the end of the shaft. The spec gives a specific pressure though not a range. Hmm.


 
Posted : 01/12/2019 7:59 pm
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When did I do that?

On almost every thread you start.

Why can’t you just explain

Do a few flexible washers really need explaining. 😉
You've still not said if the shock has ever been service and you're looking at shim stacks.
Nothing wrong with learning how to do stuff but you need to start at the beginning.


 
Posted : 01/12/2019 8:12 pm
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What’s a shockwiz going to tell me that I don’t already know?

Clearly nothing.

Or it could tell you you exact sag, your rebound is way out, or it could tell you that no matter what you do it's broken.

Or you could faff about and not make it any better.

I won't bother next time.


 
Posted : 01/12/2019 8:15 pm
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Or it could tell you you exact sag, your rebound is way out, or it could tell you that no matter what you do it’s broken.

It was a genuine question about Shockwiz. I mean, I know what my sag is, and I know the rebound is fine...

You’ve still not said if the shock has ever been service

I don't know if the damper has been serviced, but I did the air can myself a few months ago. I didn't touch the damper - but I'll check the IFP pressure now I know it's there.

Do a few flexible washers really need explaining.

I know they are there, and I know what they do, but having just read about it it's actually not that simple. Good job someone else on the internet is more helpful than you 🙂


 
Posted : 01/12/2019 8:23 pm
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This might be useful - different RS shock(s), same principles:

https://www.pinkbike.com/news/RockShox-Rear-Shock-Tuning-Experience.html

Also:

https://www.bikeradar.com/blog/the-shock-of-your-life/

https://forums.mtbr.com/shocks-suspension/rockshox-monarch-rt3-shim-stack-792842.html

And loads more. I found them using one of those search engine thingees 🙂

Edit: 'monarch shock shim tuning' was what I searched, but without the quote marks.


 
Posted : 01/12/2019 8:30 pm
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on a similar note could I replace a MM tune Monarch Plus shock with an ML tuned shock if I wanted a slightly more plush ride?


 
Posted : 07/12/2019 9:36 pm
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Anyone?


 
Posted : 08/12/2019 12:10 pm
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on a similar note could I replace a MM tune Monarch Plus shock with an ML tuned shock if I wanted a slightly more plush ride?

I did this when I 'upgraded' from a Monarch (no bands) to a Monarch Plus (came with 5) and it did make a noticeable difference. Currently trying to get my Plus right.. I think it is still a little too soft with 2 bands, so will be adding a third later today.

Bought a ShockWiz last month to try and help and am still playing with settings...

NB. I am a novice.


 
Posted : 08/12/2019 1:05 pm
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2013 frame. Original shock? Not sure if it's been serviced? Get the thing serviced... Both air can and damper.


 
Posted : 08/12/2019 7:02 pm
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I did the air can myself. Bought the special pump to get 500psi in the damper, read the instructions too.


 
Posted : 08/12/2019 7:05 pm
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on a similar note could I replace a MM tune Monarch Plus shock with an ML tuned shock if I wanted a slightly more plush ride?

If the second letter signifies compression (rather than rebound) then yes, sounds like a good move. Done similar myself before.


 
Posted : 08/12/2019 7:19 pm
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I think it’s medium rebound, low compression. I figure I could always stiffen it up with the 3 position compression adjuster. I never run it fully locked out anyway.


 
Posted : 08/12/2019 8:39 pm
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A proper service is more than just the air can though. There are loads of other seal in the damper, and eventually nitrogen (or air) gets from behind the IFP into the oil side.

It is doable at home but really need proper shaft clamps and need to know the IFP height. Just as easy to get to get ti done properly.


 
Posted : 08/12/2019 9:23 pm
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J-Tech tuned the monarch R off my son's old ripcord. Made a huge difference to the bike.

I wouldn't bother trying to do it yourself.

As for the MM to ML - send it off for proper tuning.


 
Posted : 09/12/2019 8:12 am
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I don’t know if the damper has been serviced, but I did the air can myself a few months ago. I didn’t touch the damper – but I’ll check the IFP pressure now I know it’s there.

I'd start off with a full service (and tune) ... then start home servicing from there or you're shooting in the dark.


 
Posted : 09/12/2019 9:43 am
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Bought the special pump to get 500psi in the damper, read the instructions too.

If you've just shoved 500PSi in an unserviced shock then I wouldn't be surprised if the performance is ropey. As mentioned above, the nitrogen is now likely mixed with the oil and you've just shoved in yet more gas


 
Posted : 09/12/2019 10:29 am
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on a similar note could I replace a MM tune Monarch Plus shock with an ML tuned shock if I wanted a slightly more plush ride?

Having fiddled and replaced the shim stacks on a monarch RT3 before, the only difference is probably a single shim difference. The shim stacks are mostly not very complex. You could remove this easily during a service to get the lower compression tune without having to buy a new shim stack. Huge amounts of information on MTBR on this topic if your willing to read through it all.


 
Posted : 09/12/2019 11:38 am
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If you’ve just shoved 500PSi in an unserviced shock then I wouldn’t be surprised if the performance is ropey. As mentioned above, the nitrogen is now likely mixed with the oil and you’ve just shoved in yet more gas

Suggest you read back carefully.

The shock needs a service, I have now bought the tools and read the instructions in preparation for said service.


 
Posted : 09/12/2019 12:25 pm
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Thanks @balfa. The issue I have is my monarch plus rc3 has developed the dreaded weird notchy sag issue. Its going to be a minimum of £120 once I've sent it off for service plus any parts that need replacing. I've found a brand new Monarch Plus Rc3 for £179 except its the ML tune which would come with warranty etc. Doing some reading around leverage ratios and shock tunes etc suggests that the ML tune wont suit my frame, as its firmly in the middle of the "m" compression tune range. So might just plump for a service-at least I've learnt a bit about how it all works though


 
Posted : 09/12/2019 12:32 pm
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Suggest you read back carefully.

Pass. You lost me at "what's a shim?" "oh, i really knew what they were all along"


 
Posted : 09/12/2019 12:49 pm
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Pass.

Thanks.


 
Posted : 09/12/2019 1:18 pm
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I pulled the damper apart, shims and all, greased everything, replaced the oil with genuine rockshox stuff of the correct weight, set the IFP depth properly and pumped the IFP chamber up to 500psi. That seems to have fixed it since I can now get full travel with the correct sag, and the shock is dramatically better - far more supple and responsive.

I think someone had done a home service and used heavier oil, as previously I had the rebound set on minimum and now it's somewhere in the middle for the same damping effect. Too heavy oil would also explain not having been able to get full travel.

Up yours, singlespeedstu.


 
Posted : 14/12/2019 6:46 pm

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