Fox 38 Harshness?

[warby]

Thanks for your help. For those kind of operation you need nearly 500€ and a lot of skill.

Do you now if Fox gave a sort of warranty of this kind of problem ?

Luca

sorry not sure if this covered under warranty

 

[Mikerb]

I have Fox 38 Factory on my Whyte E180. ( 27.5 wheels) No harshness. Really plush and very progressive.
I have SAG set at 25% with 80psi air pressure. ( I am 79kg plus riding gear)
LSR 6 HSR 6 ( back from full slow)
HSC 5 LSC 10 ( back from full)
1 volume spacer
Never checked the factory tune but Whyte usually set their forks and shocks on medium for compression and rebound.

 

[Growmac]

I've found my Fox 36 Factory ebike (so 34 internals ) are incredibly sensitive to the low speed rebound being correct. One click can take them from really harsh and packing down to beautifully fluid and on a par with my coil converted Lyric Ultimates on my other bike. Worth checking.

 

[mehukatti]

I just spent two weeks riding big mountain bike parks with 2021 Fox 38 Factory. On long, rough and fast tracks my hands were getting so hammered that I actually had to stop to rest for a while. This after I had done a lower leg service just a few days before. What completely reversed the situation was that I took ALL high speed compression away (set the HS fully open). It was immediately a night and day difference, and brought that "glued to the ground" feeling out of the fork! Now in hindsight I only regret that I wasted some of the best riding days of the year with the Santa Cruz and Fox recommended suspension settings for my weight. Going forward, Instead of HS, I think I'll just put additional volume spacers into the air side to prevent bottoming out on big drops and flat landings.

 

[RickBullotta]

I just spent two weeks riding big mountain bike parks with 2021 Fox 38 Factory. On long, rough and fast tracks my hands were getting so hammered that I actually had to stop to rest for a while. This after I had done a lower leg service just a few days before. What completely reversed the situation was that I took ALL high speed compression away (set the HS fully open). It was immediately a night and day difference, and brought that "glued to the ground" feeling out of the fork! Now in hindsight I only regret that I wasted some of the best riding days of the year with the Santa Cruz and Fox recommended suspension settings for my weight. Going forward, Instead of HS, I think I'll just put additional volume spacers into the air side to prevent bottoming out on big drops and flat landings.

I've learned the same regarding Grip 2 cartridge forks and X2 shocks. Starting with HSC/LSC wide open and going from there has proven to provide the best results for me.

 

[Growmac]

Agree. I run HSC wide open on both my forks.

 

[jadias89]

Trust you, but i only search for original fox parts, thats the clue i think

Luca

You literally only need some 20wt lower lube, some 5wt PTFE lube, some SRAM Butter and a couple of plastic crush washers. In terms of tools, you’ll need a shock pump, a flush-ground socket, some hex keys and some split-ring pliers.

Absolutely no way that will come to anywhere near $500 even if you buy all your tools from the Snap-On truck and all your consumables from Fox.

 

[warby]

For anyone who wants to remove fox 38 Air spring, here is a video showing how to do it?

 

[warby]

how to rebuild the Fox 38 Air Spring

 

[MBag85]

I maybe a little late, but I had the same problems and sent them off to be stripped down. The forks were harsh, no matter what I did with fully open settings . It turned out there was enough grease in the chamber to service 50 forks.

Now they're super compliant on small bumps, no harshness either.

My settings are far from fox recommendations too!

230lbs rider
Fox 38 180mm
114psi
20%sag
LSC 12 from closed (clockwise)
HSC 6 from closed
LSR 7 from full clockwise
HSR 5 from full clockwise

Tyre : 29x2.5WT assegai DD 22psi

The fork now offers loads of grip, smooth compliance and poppy feeling when hitting jumps an no more wrist problems.

A few friends on the same forks seem to run more rebound than fox suggest and it works for them too.

 

[MTBMOTOMat]

I maybe a little late, but I had the same problems and sent them off to be stripped down. The forks were harsh, no matter what I did with fully open settings . It turned out there was enough grease in the chamber to service 50 forks.

Now they're super compliant on small bumps, no harshness either.

My settings are far from fox recommendations too!

230lbs rider
Fox 38 180mm
114psi
20%sag
LSC 12 from closed (clockwise)
HSC 6 from closed
LSR 7 from full clockwise
HSR 5 from full clockwise

Tyre : 29x2.5WT assegai DD 22psi

The fork now offers loads of grip, smooth compliance and poppy feeling when hitting jumps an no more wrist problems.

A few friends on the same forks seem to run more rebound than fox suggest and it works for them too.

Similar weight to you and I'm wondering if over time it would breakdown the grease or does it just have to be taken apart? For a fork that expensive we shouldn't have to send it off for anything. I wonder if its just a batch of them or are they all coming that way? I have the option to go with a 38 or zeb and I want to drop the fork on and start riding asap.

 

[MBag85]

Similar weight to you and I'm wondering if over time it would breakdown the grease or does it just have to be taken apart? For a fork that expensive we shouldn't have to send it off for anything. I wonder if its just a batch of them or are they all coming that way? I have the option to go with a 38 or zeb and I want to drop the fork on and start riding asap.

It was that bad I couldn't ride for more than a couple miles before the wrists started hurting so I had no choice but get them sorted. After researching the issue online, it seems this has been a problem for several years ?.

I loved the Zeb but honestly now the 38 is sorted, it's loads better.

Anyone reading this, highly recommended you dial in a few clicks more rebound too!

 

[MTBMOTOMat]

It was that bad I couldn't ride for more than a couple miles before the wrists started hurting so I had no choice but get them sorted. After researching the issue online, it seems this has been a problem for several years ?.

I loved the Zeb but honestly now the 38 is sorted, it's loads better.

Anyone reading this, highly recommended you dial in a few clicks more rebound too!

Ok great to hear!

 

[Gyre]

It was that bad I couldn't ride for more than a couple miles before the wrists started hurting so I had no choice but get them sorted. After researching the issue online, it seems this has been a problem for several years ?.

Yeah, this issue has been going on for a long time. Whoever builds these forks for Fox consistently screws this up, and Fox doesn't have the QA processes or the interest to reject them. If they just pulled a few forks at random and inspected/tested them properly this would have ceased to be an issue long ago.

I loved the Zeb but honestly now the 38 is sorted, it's loads better.

That's good to hear. My 38 isn't as bad as it was when I made the original post (increasing fork pressure reduced sag and actually helped performance), but it's still nowhere near the Zeb. I haven't yet had the time to set the fork aside and take it apart, so hopefully it'll turn out to have been packed with grease and easily sorted.

 

[Jersey Skier]

Two rides in on Vorsprung Secus and it has transformed this fork. Super plush as I had hoped. I would have gone straight to coil, but those were backordered longer. No need now.

 

[Gyre]

Two rides in on Vorsprung Secus and it has transformed this fork. Super plush as I had hoped. I would have gone straight to coil, but those were backordered longer. No need now.

Nice. Are you running any tokens?

As an aside, if you notice the fork losing pressure, one of the bolts at the footstud assembly of the Secus sometimes isn't torqued right from the factory, resulting in a very slow leak. Spraying some soapy water around it will help spot any issue.

 

[Jersey Skier]

Nice. Are you running any tokens?

As an aside, if you notice the fork losing pressure, one of the bolts at the footstud assembly of the Secus sometimes isn't torqued right from the factory, resulting in a very slow leak. Spraying some soapy water around it will help spot any issue.

I had two tokens and left them as is for now. I have a Shockwiz hooked up and waiting to see what it says.

 

[Motohawk75]

I’ve found my 38s on the Bullit to be a bit harsh, I’m also not using all the travel so being advised to remove the tokens …. I done this on my zebs but they bottomed with all te tokens out …..
anyone else on 38’s running zero or 1 token with 20% sag that can give a perspective….. I’m chasing that pillow plush feel / with out bottoming to easy

 

[Jersey Skier]

….. I’m chasing that pillow plush feel / with out bottoming to easy

This is why I added the Secus to my 38. I don't think it's possible to get a stock 38 to feel like you want no matter how you set it up. I'm sure some revalving would work, but slapping on the Secus is a simple quick fix.

 

[Gyre]

Here's a Secus with some XHF 50mm heat shrink tubing to protect the barrel. It's reasonably thick and tough for what it is.

 

[Motohawk75]

Big thanks to @MBag85 for all the help and advice set up on my 38’s ? zero tokens - 20% sag with just over 100psi after a good few cycles every 20psi when inflating and there now like butter ??

 

[Mikerb]

Big thanks to @MBag85 for all the help and advice set up on my 38’s ? zero tokens - 20% sag with just over 100psi after a good few cycles every 20psi when inflating and there now like butter ??

View attachment 71483

Well done. I believe the problem for most is the harder tune the brands tend to specify for the forks whereas the standard factory tune is medium. That stiffer tune coupled with one or two tokens means the recommended air pressure for anyone other than a heavyweight or a pro downhiller is much too high. My Fox 38s on my Whyte E180 are medium tune throughout but even so my air pressure is below the Fox recommendation and I go for c 27% SAG and very little HSC............unless I am expecting bigger drops in which case I dial up HSC a couple of clicks and match that with more rebound. In both setting the fork is super plush but with good ramp and no bottom out.

 

[Gyre]

I had a chat with one of the reps at Diaz Suspension Designs. They said that the 38s have basically no support for the first 10mm of travel, so a 160 fork basically rides like a 150. They advised sizing up the air spring to compensate.

 

[Jersey Skier]

Secus was great until I upgraded the rear to coil shock. Then the front end couldn't compare to the rear. So I ordered a Smashpot to even things out.

 

[Mikerb]

I had a chat with one of the reps at Diaz Suspension Designs. They said that the 38s have basically no support for the first 10mm of travel, so a 160 fork basically rides like a 150. They advised sizing up the air spring to compensate.

...not in my experience.........but then they probably have a big stock of air springs to sell!!

 

[MBag85]

I had a chat with one of the reps at Diaz Suspension Designs. They said that the 38s have basically no support for the first 10mm of travel, so a 160 fork basically rides like a 150. They advised sizing up the air spring to compensate.

I disagree with this and would avoid going to them moving forward. I've had 3 bikes all with 38s and stantion is always true and as stated.

Given there's a couple mm at most that sits in the fork by design , I've always felt support throughout travel.

Seems a worrying statement for any reputable tuning company to make...

 

[Mikerb]

I disagree with this and would avoid going to them moving forward. I've had 3 bikes all with 38s and stantion is always true and as stated.

Given there's a couple mm at most that sits in the fork by design , I've always felt support throughout travel.

Seems a worrying statement for any reputable tuning company to make...

Rockshox air spring sat down 10mm under its own weight prior to the arrival of the 2021 Debonair...............maybe he is confusing it with that?

 

[Gyre]

I disagree with this and would avoid going to them moving forward. I've had 3 bikes all with 38s and stantion is always true and as stated.

Given there's a couple mm at most that sits in the fork by design , I've always felt support throughout travel.

Seems a worrying statement for any reputable tuning company to make...

Good to know. For what's it's worth, mine sags about 5mm on the bike's weight alone with the front end propped up slightly in the stand, so while their 10mm claim seems a little high, what I'm seeing does seem like a lot of sag without a rider.

 

[j.e.]

My 38 sags about 10 mm on the weight of the bike, too. How do I have to consider this in setting up my sag/air pressure? Is it part of the sag setting?

 

[Mcharza]

My 38 sags about 10 mm on the weight of the bike, too. How do I have to consider this in setting up my sag/air pressure? Is it part of the sag setting?

Have you already checked this?
- If the fork sucked down after you lowered your air pressure, cycle the fork several times to equalize positive and negative pressure

How to do this?
- Take the wheel off. Put the axle back on. Put the end of fork on something soft. Stick your foot on the axle. Pull up on the handlebars until you are fully extended and hit the stop. Push the fork down. Cycle the fork this way several times.