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Discussion Starter · #1 · (Edited)
I'm trying to set up my 2021 Fox 38 Grip 2 factory fork and after two rides it's harsh as hell! I am bouncing all over the place and it feels like the rebound is way too fast.

My settings are:
Riding weight 200 lbs
PSI 95
Sag 25% (42mm of sag on 170mm fork)
Tokens installed 0
HSC open
LSC 2 clicks of damping cw from open
HSR closed (Fox recommends 2 clicks out from fully closed which I tried and was way harsh)
LSR closed (Fox recommends 3 clicks out from fully closed which I tried and was way harsh)

I have checked the air spring and made sure there is not a ton of grease in the negative chamber which Fox forks are known for. I have also made sure there is no air in the lowers by pressing the bleed buttons. I am getting about 95% travel out of the fork on big hits which makes me think the air pressure and compression are good and the harshness is not coming from there.

Anyone have any ideas? Fox does not list a slow rebound tune on their website but it looks like the rebound valving diagram lists three 17.35mm OD x 7mm ID x 0.10 thick shims that make up the rebound shim stack. I was really hoping to not have to mess with the valves though. Something just seems off.
 

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currently messing around with a mullet setup.
front 29er: 2.5 assegai exo+ 23-24psi on a 30mm ID rim
rear 27.5: 2.4 dhr2 exo+ 26-28psi on a 30mm ID rim(with a tannus insert)

my riding weight is around 190 and im running 100 psi.
can't remember how many tokens.

all clicks are from closed:
lsc: 8 (fox recommends 10, yeti recommends 10-12)
lsr: 8 (fox recommends 4-5, yeti recommends 7-9)
hsc: 5 (fox recommends 5, yeti recommends 5)
hsr: 5 (fox recommends 3-4, yeti recommends 7)

it's been a decent setup so far for me.

why do u run hsr and lsr fully closed? does a few clicks from closed make it any faster or comfy?
 

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Resident Gear Head
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Discussion Starter · #3 ·
I was running HSR and LSR closed because I felt like the fork was rebounding too fast and bouncing me all over the place although now I am thinking that might not have been the issue. I've put in two tokens (Fox factory installed tokens at 170mm of travel) and have dropped the air pressure down to 90 psi to achieve the same 25% sag. I've sped up the HSR to 4 clicks out from closed and LSR to 5 clicks out from closed which are both Fox's recommended settings for my weight and psi.

I was just reading a thread here LUFTKAPPE in a Fox 38? where @Dougal mentioned the midvalve on the Grip2 is pretty tight and running rebound closed can actually have a big effect on damping.

I am thinking there is a possibility I had the air spring too high and the rebound too slow.
 

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You are on the right track. As you were not using full travel with no tokens, remove them and put your pressure back up (you may want to even try a little higher than you were, as running too far in the sag puts the fork in the steep part of the spring curve, so you get harsheness). Too much rebound will cause the fork to pack down and be harsh. Try backing out the rebound further until you start losing traction, then add a bit back in. Try taking out some rebound in the rear to balance the feel.
 
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I've found the factory setting of VVC on rebound to vary hugely on GRIP2 dampers. Because the VVC sets the HSR damping range it changes how both LSR and HSR clicks work. Fox have a method for setting up VVC in their drawings, but the stock forks vary hugely.

Basically there is no way to rely on Fox's recommendations for the number of clicks.

As for compression damping. The F38 has very little compression damping stock and you need more than you're running. This likely means you're running more air pressure than you should to compensate.
 

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Possibly the rebound too slow for sure, you never want the LSR to be closed but I would also try more compression damping. Using most of the travel isn't and indication at all of damping and most rebound complaints are actually from too little compression, as it uses too much travel and loads up the spring too far. The 38 Grip 2 damper has a very soft tune so there is no risk of harshness from too much damping at 95kg
 

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I feel like your trying to go softer and slower but that's possibly the wrong direction. Fox recommend 15-20% sag so at 25% your sat low in the travel.

Personally i run 102-106psi at 180lds and that feels good, when i did try dropping lower pressure it felt worse as i was sat in the deeper in the stroke. I also run slightly faster rebound than FOX recommend also.
 

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I'm a manly 220lbs. This is where I am with mine:

-180mm travel with the equivalent to one spacer (I have the Luftkappe in mine)
-Air pressure is at 125
-HSC is 4 or 5 out from closed
-LSC is about halfway out from closed. I can't tell because you can't feel the clicking in the LSC on the Grip2 dampers
-HSR is I think 3 out from closed
-LSR is about 5 out from closed

DO NOT run the HSR fully closed. It makes the whole fork harsh. I've messed around a lot with this fork and I think 2 clicks out from closed is the furthest you can go.

Honestly, I'd go back to the drawing board and start fresh: 2 tokens, both compression adjusters at the halfway point, HSR 3 clicks out and LSR about 7 or 8 out.

I don't think the Fox 38 was designed to be super plush or whatever. I refer to it as 'sport' suspension: It can feel rough and tight at times but it'll track well. For what it's worth... I've had wayyyy more difficulty setting up the Fox 38 compared to the 2021 Fox 40.

Also, don't rely on the 'not using full travel'. It's not an indicator that your fork isn't set up well. I did bottom out my 40 last week when I washed out in a dry berm and all my weight came down on the handlebars. That extra bit of unused travel might have helped me a bit.
 

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I'm 205 lbs and run 115 psi, LSR 7, and HSR 3. I thought the recommended rebound was too slow and definitely made the fork feel harsh. Everyone's first instinct to deal with harshness is to drop pressure and back off compression but often they'd be better off running their rebound faster and removing volume spacers then reassessing pressure and compression.
 

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I had a good setup on my 36 Grip 2 damper and now I’m feeling it’s too harsh. Couple of questions:

When you do the click adjustments, it’s always clicks OUT from fully closed—I.e. counter clockwise clicks to the desired number, right?

Second, when you start counting clicks, so you start from fully closed or do you go to the first click position first? Fully closed usually doesn’t line up with a proper click so I’ve been considering the first click position as 0 and counting up from there.
 

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I had a good setup on my 36 Grip 2 damper and now I'm feeling it's too harsh. Couple of questions:

When you do the click adjustments, it's always clicks OUT from fully closed-I.e. counter clockwise clicks to the desired number, right?

Second, when you start counting clicks, so you start from fully closed or do you go to the first click position first? Fully closed usually doesn't line up with a proper click so I've been considering the first click position as 0 and counting up from there.
Counting from closed is the normal way.

I usually count the first discernable click as my zero point. This is partially because Fox lists 0 clicks in some of their tuning guides (ex 2021 X2) and it makes more sense to me.
 

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Counting from closed is the normal way.

I usually count the first discernable click as my zero point. This is partially because Fox lists 0 clicks in some of their tuning guides (ex 2021 X2) and it makes more sense to me.
interesting, i count the very first click as 1. even if it can't turn anymore clockwise. i thought i heard a fox tech in the dialed series say the first click is always 1.
 

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interesting, i count the very first click as 1. even if it can't turn anymore clockwise. i thought i heard a fox tech in the dialed series say the first click is always 1.
Yeah Jordi counts the first click as 1, which means you have to remember to count the click you're on if you're counting to see how far from closed you are. Like I said, the manuals list zero clicks. Also personally, I think of closed = zero and the other "clicks" being how far from closed I am.
 

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It doesn’t matter if you count the fist click as zero or one, as long as you do it the same each time. The recommended settings are a starting point and manufacturing tolerances allow for variation, 4 clicks out on one fork off the assembly line may give the same dampening as another at 3 or 5. Choose a method and stick to it soyou can be consistent in setup. It is the same reason you should use the same shock pump when making adjustments.
 

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To all those mentioning closing the HSR causing harshness I too have felt that when setting up a heavier friends 2020 36 (so vvc rebound and spring/shim compression). I’m confused as to why this happens but it really does, it’s even noticeable stationary. I can see if the ports on the piston were too small that the LSR closed could cause an issue but the HSR is increasing the force on the shims on the opposite side of the piston so it shouldn’t be effecting flow through the LSR port or mid valve. Really strange effect.
 

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It doesn't matter if you count the fist click as zero or one, as long as you do it the same each time. The recommended settings are a starting point and manufacturing tolerances allow for variation, 4 clicks out on one fork off the assembly line may give the same dampening as another at 3 or 5. Choose a method and stick to it soyou can be consistent in setup. It is the same reason you should use the same shock pump when making adjustments.
yeah i figured as much. stay consistent with how you count and track
 

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To all those mentioning closing the HSR causing harshness I too have felt that when setting up a heavier friends 2020 36 (so vvc rebound and spring/shim compression). I'm confused as to why this happens but it really does, it's even noticeable stationary. I can see if the ports on the piston were too small that the LSR closed could cause an issue but the HSR is increasing the force on the shims on the opposite side of the piston so it shouldn't be effecting flow through the LSR port or mid valve. Really strange effect.
Too much rebound damping causes the fork to ratchet down and generally ride lower in its travel so the harshness is from being in a region with a higher spring rate. Due to the overlap of adjusters it can be caused by either the LSR or HSR knob but generally its a low speed rebound thing
 

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Clicker position is not going to fix those dampers. But it can be used to minimise the problems.

For rebound you can create the extreme cases with the GRIP2 system. Intentionally or otherwise.

If you wind in too much LSR and not enough HSR you can end up with a digressive rebound curve. One that feels dead and has no pop, but doesn't have enough high speed damping and feels unstable recovering from deep compression.

If you wind in too much HSR and not enough LSR you can end up with a progressive rebound curve that feels poppy and lively but can't follow the ground at speed.

Finding the middle ground is difficult without a dyno. Because the factory clocking of the HSR (VVC) is extremely sensitive to preload and the factory preload is varying by about 20%.
My best suggestion (on GRIP2 only) is to set HSR in the middle of the range before adjusting LSR.
 

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My best suggestion (on GRIP2 only) is to set HSC in the middle of the range before adjusting LSC.
Would you recommend the same approach for pre-vvc grip 2? Seems for me there's no middle ground between supportive and spikey. Currently run a bit more LSC vs HSC. On the rebound side I run near equal but echo your thoughts on rebound behavior there.

Sent from my Pixel 4a (5G) using Tapatalk
 

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Would you recommend the same approach for pre-vvc grip 2? Seems for me there's no middle ground between supportive and spikey. Currently run a bit more LSC vs HSC. On the rebound side I run near equal but echo your thoughts on rebound behavior there.

Sent from my Pixel 4a (5G) using Tapatalk
So I wrote HSC/LSC all through that post where it should have been HSR/LSR. Which made the post really really confusing.
I've fixed it now.

You absolutely don't want to run HSC in the middle before setting LSC. You want to run HSR in the midd before setting LSR.

All GRIP2 (2018-2020 and 2021+) use the same VVC adjustment on the rebound damper. For 2021 they used it on the compression too.
 
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