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Rear shock advise
 

[Closed] Rear shock advise

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[#10882087]

Got a 150 rear travel full suss but I’m not happy with it , doesn’t matter how much air you put in the sag just won’t sit right .so I’m looking at getting 1 with the extra can on it , thing is it’s 190 x 51 so will any shock that’s 190 long fit my frame , where does the 150 travel come from the shock or the frame , and can I fit say a 200mm shock . Confused.com


 
Posted : 25/10/2019 7:38 pm
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190 is the length of the shock, eye to eye. 51 is the stroke of the shock. Ideally you need to keep these measurement the same.


 
Posted : 25/10/2019 7:41 pm
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RS Monarch RS3 available in 190 * 51
https://www.tftuned.com/monarch-plus-rc3-debonair-2018/p3117


 
Posted : 25/10/2019 7:53 pm
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Why didn’t I think of that . Cheers


 
Posted : 25/10/2019 7:54 pm
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150mm is the amount the wheel moves relative to the frame. As mentioned 51mm is the stroke of the shock and 190mm is the overall length.
I'd research setting up what you have or find a helpful shop before spending on a new one.


 
Posted : 25/10/2019 8:57 pm
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I’d research setting up what you have or find a helpful shop before spending on a new one.

That could well save you a lot of money.

I had a monarch on a Nomad and took a while to get it running sweet. Perfect sag meant it blew through travel. More air to stop.it blowing through meant sag was half what it should be and was very hard in the initial and mid strokes. Spent a bit of time faffing with reducer bands and got it dialed in and running sweet.

OP - what shock on which bike?


 
Posted : 25/10/2019 9:48 pm
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The travel is a combination of the shock stroke and frame design. You have a 50 mm stroke shock, which gives 150 mm travel on that frame. That means you have an average leverage ratio of 3:1. If you put a 200 x 50 mm shock on, the back of the bike would sit up an inch or more higher, but you wouldn't get any more travel (this is a bit tricky though, because the leverage ratio will vary a bit throughout the travel, so the actual changes will vary according to the specific frame design). That's assuming the longer shock will fit, of course. In general, putting a longer or shorter shock on is not a good idea. It's not impossible that it will be an improvement, but it's much more likely to cause problems. I would only try that if I had different shocks on hand and wanted to experiment a bit.

As above, playing with air volume spacers is the obvious place to start. Otherwise, buy the same sized shock with more adjustability and start adjusting.


 
Posted : 26/10/2019 12:15 am
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So... How much sag are you trying to achieve? And how are you measuring it?


 
Posted : 26/10/2019 5:52 am
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It’s a rockshox monarch , I’m pumping nearly 300psi in to it to get near to 25-30% sag,I’ve tried playing with spacers but doesn’t seem to make any difference, also when I re attach the shock pump to it I haven’t got 300 psi anymore but that could just be air loss back into the pump


 
Posted : 26/10/2019 9:14 am
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Sounds to me like the negative chamber has been overpressurized (unless you weigh 150 kg).


 
Posted : 26/10/2019 9:18 am
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Have you tried pumping it up in stages, cycling the shock a few times then adding more air?
There is probably a sticker with what tune you want if you need a new one.
Probably something like MM or ML.


 
Posted : 26/10/2019 11:01 am
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It’s a rockshox monarch , I’m pumping nearly 300psi in to it to get near to 25-30% sag,

I'd start off with letting all the air out and begin from scratch.
Remove all volume reducing bands
Turn all dials to minimum/off settings
Pump up to 75psi and cycle shock several times
Pump up to 125psi and cycle shock several times
Pump up to 175psi and cycle shock several times
(At some point whilst carrying out the above the Negative chamber will equalise)
Repeat until you achieve the correct sag
Remember pressure
Ride and adjust bottom out with volume bands as required to stop bottom out

I was bout 82kg fully kitted up and ran approx 215psi to achieve 30% sag on my Nomad

One other thing - Is the shock in warranty?? (2yrs from new if you're the original owner) as might be an issue that is covered


 
Posted : 26/10/2019 1:12 pm
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What bike is it? 3:1 Leverage ratio on an air shock is always going to be sub optimal.

Back in ye day I had a couple of frames that had 3:1 leverage and even though I'm a 65kg skinny git I needed to run custom tuned coils to get them to work properly. I did try an air shock on 1 bike, but it lasted a matter of weeks before failing.


 
Posted : 26/10/2019 1:32 pm