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Discussion Starter · #1 ·
Hello all, I have a few questions regarding forks, I'm hoping some of you have direct experience in this...

My weight (kitted up) is about 265, I don't ride jump trails, and rarely do any drops more than 12" or so (I know, lame, but at my age & weight...I don't heal like I use to LOL).

I have recently installed a 2018 Rockshox Pike RCT3 on my Kona Honzo, so far it's been an absolute dream to ride...these 35mm stanchions seem perfect for us heavier riders. :thumbsup:

I know very little about the Charger damper, but it seems like a quality piece for sure, and I'm still tinkering with the low speed compression and rebound settings.

So, the question...I have the fork currently set at the manufactures maximum pressure of 163, based on a 120mm fork (factor +/- 1 or 2 psi using a Rockshox shock pump), even at this max pressure I'm still only able to get 30% sag...I'd really prefer to get that closer to 20%, but it would appear I'm maxed on pressure??

Now, that said, I don't do big jumps, and as such have never bottomed it out, but I've been close....and I'd like a little more insurance there.

According to the factory manual, the fork came with 4 bottomless tokens installed (I haven't confirmed this), and the 120mm fork can accept up to 6 tokens...I have 2 extra in the box...would adding these last 2 tokens help at all with me getting my sag closer to 20%?? or are the tokens used for a different purpose all together?

Sorry if these are stupid questions, but even after watching some setup videos, I'm having a difficult time understanding the correlation between spring pressures & bottomless tokens as applied to fork sag. :confused::madman:

Thanks for any help! :)
 

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Something seems off... I ride a Yari (Pike minus the Charger) that use to be 120mm. I am heavier than you, but I only ran 105-110psi in it to get the 20% sag with 4 tokens. Now the fork is 140mm and I run it at 95 psi with 4 tokens.
 

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Discussion Starter · #3 ·
Something seems off... I ride a Yari (Pike minus the Charger) that use to be 120mm. I am heavier than you, but I only ran 105-110psi in it to get the 20% sag with 4 tokens. Now the fork is 140mm and I run it at 95 psi with 4 tokens.
Yeah, it seems like I should be able to get my sag better than what I have...

Maybe I'll just start from scratch...empty the spring, pull the top to confirm I've got the right amount of tokens, and start all over.
 

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Something seems off... I ride a Yari (Pike minus the Charger) that use to be 120mm. I am heavier than you, but I only ran 105-110psi in it to get the 20% sag with 4 tokens. Now the fork is 140mm and I run it at 95 psi with 4 tokens.
The newer Pikes require more pressure. I'm 215 lbs and run 110-113 psi with 3 tokens in my 2019 Pike RC.

OP, why do you want the sag lower? Do you want the fork stiffer?
 

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Discussion Starter · #5 ·
OP, why do you want the sag lower? Do you want the fork stiffer?
No, not so much stiffer, just looking at overall travel.

So I'm probably looking at this wrong (please correct me if I am)...If I have 120mm of travel, and I set my sag at 30%, that means I'm effectively using 36mm of my available travel just "sitting on the bike in the riding position" correct? If so, that means I'm only left with 84mm of available travel?

So, I assumed that if I could get my sag to 20% I'd be able to use 96mm of travel in the fork...giving me more travel before bottom out?

Or...Maybe add 1 more token, to give me more ramp up at the end to avoid near bottom outs?

This should be a simple concept, I can't believe I'm having so much trouble wrapping my head around it LOL.
 

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You sag into the travel so the fork has "negative" travel to track the ground as you ride. If you are blowing through all the travel when sag is set correctly, you need to add tokens to increase bottom out resistance.
 

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The newer Pikes require more pressure. I'm 215 lbs and run 110-113 psi with 3 tokens in my 2019 Pike RC.
That sucks... I like my Yari because I can run lower pressures even though I am far from a lower weight rider. :)
 

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Discussion Starter · #8 ·
I am far from a lower weight rider. :)
LOL, I feel ya there!

So, I think I get it now.

And that begs the question, a rider of my weight class, based on Rockshox manual, will basically never be able to set the sag much better than 30% without exceeding the manufactures max specs?

This doesn't bother me per se (because my intent is to lose more weight), but for far heavier riders, they may not even be able to achieve the 30%.

I think I'm going to stick with the 30% and pop one more token in (for a total of 5) and then see how that goes...as I said above, I've never bottomed out, but I've been close, maybe that one more token will be the answer?

Next question though...do I need to lower pressure in the fork, if I add more tokens? My brain says that if you effectively reduce the air chamber volume you could run less pressure to achieve the same (or similar) pressure??
 

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No, not so much stiffer, just looking at overall travel.

So I'm probably looking at this wrong (please correct me if I am)...If I have 120mm of travel, and I set my sag at 30%, that means I'm effectively using 36mm of my available travel just "sitting on the bike in the riding position" correct? If so, that means I'm only left with 84mm of available travel?

So, I assumed that if I could get my sag to 20% I'd be able to use 96mm of travel in the fork...giving me more travel before bottom out?

Or...Maybe add 1 more token, to give me more ramp up at the end to avoid near bottom outs?

This should be a simple concept, I can't believe I'm having so much trouble wrapping my head around it LOL.
Bottoming out occasionally is fine. Adding more tokens will increase how much force it takes to compress the fork further into the travel. At the same psi the fork will be firmer.
 

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Discussion Starter · #10 ·
Bottoming out occasionally is fine. Adding more tokens will increase how much force it takes to compress the fork further into the travel. At the same psi the fork will be firmer.
Thanks for the info!

Just for fun, I pulled the left side of the fork to see how many tokens actually did come preinstalled (for those watching, it is indeed 4, plus 2 in the box).

So I reassembled everything and pumped it back up...this time through I tried 125 PSI...and now that gives me 30% sag...WTF?? I'm going to have to assume my shock pump gauge is just plain off...time for a new pump perhaps.
 

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It's hard to measure fork sag too. This is why I generally start with the mfg recommended pressure and adjust from there based on feel. I don't even how much sag my forks have other than being roughly 18-25%.
 

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How does the spring feel? Too soft? Too hard? Just right? More tokens actually equals more sag for the same pressure.

If you think about it, more tokens means less volume and that means theres physically less of a column of air to support your body weight. More tokens also means you'll use more travel for a given hit.

If you want to reduce sag, reduce volume spacers and keep the pressure the same. It'll ride higher, use less travel off the top, and feel firmer overall. It will, however, ramp up less at the bottom. This isnt necessarily a bad thing and it doesnt necessarily mean you'll bottom out easier. More volume, same pressure, means you'll stay more in the top and middle of the travel and potentially avoid bottomout.

You can correctly set a fork without ever measuring sag. I think its actually easier. Just tune for characteristics. A saggy wallowy fork drives me nuts, so I run big volume in the positive and higher pressure. I enjoy how that works.
 

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If you think about it, more tokens means less volume and that means theres physically less of a column of air to support your body weight. More tokens also means you'll use more travel for a given hit.
It's not the volume that supports your weight, it's the pressure. More tokens means you'll use less travel for a given hit assuming initial pressure is similar.

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Discussion Starter · #14 ·
How does the spring feel? Too soft? Too hard? Just right? More tokens actually equals more sag for the same pressure.

If you think about it, more tokens means less volume and that means theres physically less of a column of air to support your body weight. More tokens also means you'll use more travel for a given hit.

If you want to reduce sag, reduce volume spacers and keep the pressure the same. It'll ride higher, use less travel off the top, and feel firmer overall. It will, however, ramp up less at the bottom. This isnt necessarily a bad thing and it doesnt necessarily mean you'll bottom out easier. More volume, same pressure, means you'll stay more in the top and middle of the travel and potentially avoid bottomout.

You can correctly set a fork without ever measuring sag. I think its actually easier. Just tune for characteristics. A saggy wallowy fork drives me nuts, so I run big volume in the positive and higher pressure. I enjoy how that works.
Thank you for the breakdown, that really helps!

As far as how the fork feels? Well I think it's a great feeling fork, I like it a lot, and it seems to absorb all of the little, AND 99% of the big hits I have...but to be fair, I have little experience with a fork of this caliber, all of my other forks have been low spec Recon forks, and compared to those, this fork is divine.

I think I will mess around with the spacers and pressure a bit more, it's easy enough to do at the trailhead...now if it would just stop raining here (has been raining for 3 days, with another week of it in the forecast. :madman:)
 

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Discussion Starter · #15 ·
It's not the volume that supports your weight, it's the pressure. More tokens means you'll use less travel for a given hit assuming initial pressure is similar.

View attachment 1252022
This is a good picture too!

It shows what's happening inside the air spring.

I think what I'm going to do as I mentioned above, I'll try some trailhead adjustments, find a pressure I think feels good, then run a lap and see how much travel I do/don't use, keep the pressure, and adjust tokens accordingly.

The fork can take a max of 6 tokens, I think I'll pop one out and start with 3, I should be able to get this at least "in the ballpark" with just an afternoon of riding...besides, it gives me a reason to grab a buddy and go burn an afternoon.
 

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Thanks for the info!

Just for fun, I pulled the left side of the fork to see how many tokens actually did come preinstalled (for those watching, it is indeed 4, plus 2 in the box).

So I reassembled everything and pumped it back up...this time through I tried 125 PSI...and now that gives me 30% sag...WTF?? I'm going to have to assume my shock pump gauge is just plain off...time for a new pump perhaps.
You need to cycle the fork to fill the negative chamber

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Discussion Starter · #17 ·
You need to cycle the fork to fill the negative chamber

Sent from my Pixel 3 XL using Tapatalk
Yep, I know.

I do think it's time for a new shock pump though, mines got a lot of miles on it, and I've suspected the gauge has been a few PSI off for a while...but not 20+ PSI off...I need to borrow a friends pump to be sure.
 

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Yep, I know.

I do think it's time for a new shock pump though, mines got a lot of miles on it, and I've suspected the gauge has been a few PSI off for a while...but not 20+ PSI off...I need to borrow a friends pump to be sure.
If you measure based on sag percentage, then you don't need to know the pressure unless you are about to open the fork and need to reset it.

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Dont get hung up on tokens. Remove them all and setup the fork for sag. If you bottom add until you dont. If you still bottom with all tokens then you will have to up the pressure further as you wont be able to run that sag percentage.

Eg. 40 psi extended your sag is 95%. All 6 tokens wont keep you from bottoming.

Eg. 110 psi extended 4 tokens 30% sag. But you bottom now and then, so add two more tokens. Result. 30% sag 6 tokens and no bottom. Fork feels smooth and soft. But moves through a bit of the top of the stroke of travel fairly easily.

Eg. 120 psi extended no tokens 30% sag, but you bottom now and then, so you add 1 token and up the compression damping a little.

Eg. 135 psi extended no tokens 24% sag. No bottoming. But fork feels a bit stiff and rides higher up. You like it for steep rougher rooty trails rather than long cross country flats.

The extended pressure is just a reference point and provides the same information as sag does. Obviously you dont want more pressure in the fork at extension than is recommended by the manufacturer. But once you know thats not happening you can just rely on sag after that.

The tuning Sag vs tokens is really a personal preference and varies with riding style/terrain. Compression damping and riding speed will also affect your suspension fork travel.

Have fun!

tip: fork has no sag markings, grab a business card and cut it to the percentage you want. Then place under the oring to verify setting when on trail/before you head out from your vehicle. Can even travel with you easily on your pack.
 

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It's not the volume that supports your weight, it's the pressure. More tokens means you'll use less travel for a given hit assuming initial pressure is similar.

View attachment 1252022
The picture is misleading or it could be... It shows the same pressure at a fixed point of compression with and without tokens. It should show a third image for each of the beginning/extended position with slightly less air in the token image.

Confusing... you have less and more air pressure in a fork with a bunch of tokens.
 
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