Suspension Component Technology/Functionality Discussion

10/23/2025 4:57pm
ZAKBROWN! wrote:

Diaz just dropped the Zeb Lower Runt so now you can double Runt.  Thoughts?

https://diazsuspensiondesign.com/the-lower-runt

TEAMROBOT wrote:
Just looked at the graphic on the Diaz site, and while it took me a minute to figure out exactly what I was looking at, dang...

Just looked at the graphic on the Diaz site, and while it took me a minute to figure out exactly what I was looking at, dang that's smart.

The lower chamber ramp in a Zeb is a real bummer, and I think (if it works as advertised), the Diaz Lower Runt looks like a great idea to fix it. Bravo.

It's a clever idea, but I take a little bit of issue with the claim of it being  "the only air spring capable of duplicating...

It's a clever idea, but I take a little bit of issue with the claim of it being  "the only air spring capable of duplicating a coil fork spring rate from the vary beginning to the end" when the Vorsprung Secus has been around for 5 years 

The secus needed to be outside the fork because of the limited air volume inside, so I guess the lower runt uses very low pressures and the negative coil spring is there to regain some kind of compliance after moving the piston upwards and reducing the negative spring volume. The positive chamber looks smaller, (especially with a runt installed) ie progressive so it seems a bit like robbing peter to pay paul?

No free lunch

 

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HexonJuan
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10/24/2025 6:45am
Sorry if I'm now spamming this, but anyone reading this thread should be interested to know Tony Foales book MOTORCYCLE HANDLING AND CHASSIS DESIGN: the art...

Sorry if I'm now spamming this, but anyone reading this thread should be interested to know Tony Foales book MOTORCYCLE HANDLING AND CHASSIS DESIGN: the art and science is back in print after 20 years, and in that time I don't think I've found a better reference book on the topic!

Get it now so you don't need to wait decades like I have to buy a copy! I've got a physical copy of the original 80's book but the second edition added a TON of excellent information that is still highly relevant

 https://a.co/d/bmfsZFI

Had gotten the PDF he had some time ago and was wondering who was spamming me when that email came through. Excellent intel inside.

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HexonJuan
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10/24/2025 7:03am

Rando thinking here in light of Robot's time on the MRP damper: Have we been setting up our forks wrong all along? 

Hear me out.

Most testers everywhere end up running more psi than the factory recommended settings and then running close to 0 turns on compression. I'll leave rebound out for the time. MRP recommending backing off psi and adding in comp damping seems to point that to be the case. Personally, I ride pretty damn close to what's called out for the forks on my bikes (Mezzer, Mattoc, 36Factory, Grip damper) and do add in a couple clicks of comp damping and haven't had any issues with finding the bottom on hits that weren't justified, the forks hoover up chatter, and I haven't noticed any significant pitching. The HBO in the Mezz and Mattoc and the IRT in the Mezz definitely account for some of that. Robot's review just kicked that thinking to the foreground for me. 

 

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j0lsrud
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10/24/2025 7:39am
HexonJuan wrote:
Rando thinking here in light of Robot's time on the MRP damper: Have we been setting up our forks wrong all along? Hear me out.Most testers...

Rando thinking here in light of Robot's time on the MRP damper: Have we been setting up our forks wrong all along? 

Hear me out.

Most testers everywhere end up running more psi than the factory recommended settings and then running close to 0 turns on compression. I'll leave rebound out for the time. MRP recommending backing off psi and adding in comp damping seems to point that to be the case. Personally, I ride pretty damn close to what's called out for the forks on my bikes (Mezzer, Mattoc, 36Factory, Grip damper) and do add in a couple clicks of comp damping and haven't had any issues with finding the bottom on hits that weren't justified, the forks hoover up chatter, and I haven't noticed any significant pitching. The HBO in the Mezz and Mattoc and the IRT in the Mezz definitely account for some of that. Robot's review just kicked that thinking to the foreground for me. 

 

Yes?

Öhlins always has a lot more damping than Fox and RS, but in the last few years (Charger 3 and GripX2) much more dampin  has been added from the big players.

I personally like a setup with more damping, i feel it are more grippy and less fatiguing to ride than a "active" setup.

3
10/24/2025 10:59am
HexonJuan wrote:
Rando thinking here in light of Robot's time on the MRP damper: Have we been setting up our forks wrong all along? Hear me out.Most testers...

Rando thinking here in light of Robot's time on the MRP damper: Have we been setting up our forks wrong all along? 

Hear me out.

Most testers everywhere end up running more psi than the factory recommended settings and then running close to 0 turns on compression. I'll leave rebound out for the time. MRP recommending backing off psi and adding in comp damping seems to point that to be the case. Personally, I ride pretty damn close to what's called out for the forks on my bikes (Mezzer, Mattoc, 36Factory, Grip damper) and do add in a couple clicks of comp damping and haven't had any issues with finding the bottom on hits that weren't justified, the forks hoover up chatter, and I haven't noticed any significant pitching. The HBO in the Mezz and Mattoc and the IRT in the Mezz definitely account for some of that. Robot's review just kicked that thinking to the foreground for me. 

 

Pretty much yes - forks for a long time typically have very little compression damping, i guess to be conservative so its harder to screw up. But things like friction and sub optimal spring curves mean adding damping feels worse so people back it out. That makes people think comprrssion damping is bad but really the root cause is somewhere else

 

The vorsprung telum manual has some great lines about the adjustment range of most stock gear

2
10/24/2025 11:01am
HexonJuan wrote:
Rando thinking here in light of Robot's time on the MRP damper: Have we been setting up our forks wrong all along? Hear me out.Most testers...

Rando thinking here in light of Robot's time on the MRP damper: Have we been setting up our forks wrong all along? 

Hear me out.

Most testers everywhere end up running more psi than the factory recommended settings and then running close to 0 turns on compression. I'll leave rebound out for the time. MRP recommending backing off psi and adding in comp damping seems to point that to be the case. Personally, I ride pretty damn close to what's called out for the forks on my bikes (Mezzer, Mattoc, 36Factory, Grip damper) and do add in a couple clicks of comp damping and haven't had any issues with finding the bottom on hits that weren't justified, the forks hoover up chatter, and I haven't noticed any significant pitching. The HBO in the Mezz and Mattoc and the IRT in the Mezz definitely account for some of that. Robot's review just kicked that thinking to the foreground for me. 

 

j0lsrud wrote:
Yes?Öhlins always has a lot more damping than Fox and RS, but in the last few years (Charger 3 and GripX2) much more dampin  has been...

Yes?

Öhlins always has a lot more damping than Fox and RS, but in the last few years (Charger 3 and GripX2) much more dampin  has been added from the big players.

I personally like a setup with more damping, i feel it are more grippy and less fatiguing to ride than a "active" setup.

The funny thing is, an optimised set up can still retain more of the "active" feel along with decent support and stability. You still make a compromise somewhere buts its much less than what most peope are used to

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HexonJuan
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10/24/2025 1:31pm
HexonJuan wrote:
Rando thinking here in light of Robot's time on the MRP damper: Have we been setting up our forks wrong all along? Hear me out.Most testers...

Rando thinking here in light of Robot's time on the MRP damper: Have we been setting up our forks wrong all along? 

Hear me out.

Most testers everywhere end up running more psi than the factory recommended settings and then running close to 0 turns on compression. I'll leave rebound out for the time. MRP recommending backing off psi and adding in comp damping seems to point that to be the case. Personally, I ride pretty damn close to what's called out for the forks on my bikes (Mezzer, Mattoc, 36Factory, Grip damper) and do add in a couple clicks of comp damping and haven't had any issues with finding the bottom on hits that weren't justified, the forks hoover up chatter, and I haven't noticed any significant pitching. The HBO in the Mezz and Mattoc and the IRT in the Mezz definitely account for some of that. Robot's review just kicked that thinking to the foreground for me. 

 

j0lsrud wrote:
Yes?Öhlins always has a lot more damping than Fox and RS, but in the last few years (Charger 3 and GripX2) much more dampin  has been...

Yes?

Öhlins always has a lot more damping than Fox and RS, but in the last few years (Charger 3 and GripX2) much more dampin  has been added from the big players.

I personally like a setup with more damping, i feel it are more grippy and less fatiguing to ride than a "active" setup.

The funny thing is, an optimised set up can still retain more of the "active" feel along with decent support and stability. You still make a...

The funny thing is, an optimised set up can still retain more of the "active" feel along with decent support and stability. You still make a compromise somewhere buts its much less than what most peope are used to

Kinda my point. We've all read reviews where the tester sets their goods up way outta spec (Say 5-10psi+) and then little to no compression damping, people of all sizes too. I know it ain't 'correct', but I've been turning the comp knob to 2 or 3 from open and then setting sag. It's ended up near factory psi recommendations and hasn't really shown a detriment on dirt. It allows a quick click or 2 in either direction to make a lot of change for terrain (flow or chunk). It just seems weird that near every mfr is off by that much on their recommended settings, especially with certain testers from other sites/mags. 

2
10/24/2025 3:34pm

I have a v1 Era, so I'm definitely not running too little damping haha

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TEAMROBOT
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10/24/2025 4:10pm
HexonJuan wrote:
Kinda my point. We've all read reviews where the tester sets their goods up way outta spec (Say 5-10psi+) and then little to no compression damping...

Kinda my point. We've all read reviews where the tester sets their goods up way outta spec (Say 5-10psi+) and then little to no compression damping, people of all sizes too. I know it ain't 'correct', but I've been turning the comp knob to 2 or 3 from open and then setting sag. It's ended up near factory psi recommendations and hasn't really shown a detriment on dirt. It allows a quick click or 2 in either direction to make a lot of change for terrain (flow or chunk). It just seems weird that near every mfr is off by that much on their recommended settings, especially with certain testers from other sites/mags. 

Great question. I think that most stock forks have an underdamped compression shim stack for aggressive riders, so those reviewers are likely trying to get more support out of the fork in high shaft speed scenarios, and the only option (without a re-tune) is to add more air pressure, or tokens, or both.

Cranking the compression knobs on a fork with too light of a compression tune at the shimstack essentially makes for a digressive fork tune- it gives you high damping force on LSC, high damping force on mid-speed (which is the shaft speed that an average HSC knob actually affects), and then soft on HSC (determined by the shim stack). This setup is going to feel harsh off the top. The alternative is opening the LSC and HSC knobs until they feel consistent-ish with the compression shim tune, and then adding lots of air to give you support.

So it's wrong in the platonic sense of an "optimal setup," but it makes sense as the pragmatic solution to that specific problem.

It's also what makes the Lift so cool in my eyes. @j0lsrud mentioned Ohlins forks running more damping, and I totally agree. I got to spend one day on an RXF38 at the Vital Enduro Bike Test Sessions and was super impressed. It felt better everywhere, similar in many ways to the Lift, but maybe even more damped feeling. That's what has me excited to experiment with an even stiffer shim stack on my Lift.

3
10/24/2025 4:16pm Edited Date/Time 10/24/2025 4:19pm
j0lsrud wrote:
Yes?Öhlins always has a lot more damping than Fox and RS, but in the last few years (Charger 3 and GripX2) much more dampin  has been...

Yes?

Öhlins always has a lot more damping than Fox and RS, but in the last few years (Charger 3 and GripX2) much more dampin  has been added from the big players.

I personally like a setup with more damping, i feel it are more grippy and less fatiguing to ride than a "active" setup.

The funny thing is, an optimised set up can still retain more of the "active" feel along with decent support and stability. You still make a...

The funny thing is, an optimised set up can still retain more of the "active" feel along with decent support and stability. You still make a compromise somewhere buts its much less than what most peope are used to

HexonJuan wrote:
Kinda my point. We've all read reviews where the tester sets their goods up way outta spec (Say 5-10psi+) and then little to no compression damping...

Kinda my point. We've all read reviews where the tester sets their goods up way outta spec (Say 5-10psi+) and then little to no compression damping, people of all sizes too. I know it ain't 'correct', but I've been turning the comp knob to 2 or 3 from open and then setting sag. It's ended up near factory psi recommendations and hasn't really shown a detriment on dirt. It allows a quick click or 2 in either direction to make a lot of change for terrain (flow or chunk). It just seems weird that near every mfr is off by that much on their recommended settings, especially with certain testers from other sites/mags. 

The issue with a lot of stock dampers is that not only do they not offer a lot of support from compression damping, but they also get harsh quickly when the adjusters are closed to increase damping. 

For example the Grip2 chokes and gets peaky/ harsh when LSC is closed, so that limits the amount of damping range is usable. 

Less damping feels good in a show room and in a parking lot, but falls short when riding harder. More damped setups feel less impressive on the showroom but feel better the faster /harder they are ridden. 

2
10/24/2025 4:24pm Edited Date/Time 10/24/2025 4:25pm
HexonJuan wrote:
Kinda my point. We've all read reviews where the tester sets their goods up way outta spec (Say 5-10psi+) and then little to no compression damping...

Kinda my point. We've all read reviews where the tester sets their goods up way outta spec (Say 5-10psi+) and then little to no compression damping, people of all sizes too. I know it ain't 'correct', but I've been turning the comp knob to 2 or 3 from open and then setting sag. It's ended up near factory psi recommendations and hasn't really shown a detriment on dirt. It allows a quick click or 2 in either direction to make a lot of change for terrain (flow or chunk). It just seems weird that near every mfr is off by that much on their recommended settings, especially with certain testers from other sites/mags. 

TEAMROBOT wrote:
Great question. I think that most stock forks have an underdamped compression shim stack for aggressive riders, so those reviewers are likely trying to get more...

Great question. I think that most stock forks have an underdamped compression shim stack for aggressive riders, so those reviewers are likely trying to get more support out of the fork in high shaft speed scenarios, and the only option (without a re-tune) is to add more air pressure, or tokens, or both.

Cranking the compression knobs on a fork with too light of a compression tune at the shimstack essentially makes for a digressive fork tune- it gives you high damping force on LSC, high damping force on mid-speed (which is the shaft speed that an average HSC knob actually affects), and then soft on HSC (determined by the shim stack). This setup is going to feel harsh off the top. The alternative is opening the LSC and HSC knobs until they feel consistent-ish with the compression shim tune, and then adding lots of air to give you support.

So it's wrong in the platonic sense of an "optimal setup," but it makes sense as the pragmatic solution to that specific problem.

It's also what makes the Lift so cool in my eyes. @j0lsrud mentioned Ohlins forks running more damping, and I totally agree. I got to spend one day on an RXF38 at the Vital Enduro Bike Test Sessions and was super impressed. It felt better everywhere, similar in many ways to the Lift, but maybe even more damped feeling. That's what has me excited to experiment with an even stiffer shim stack on my Lift.

TLDR:

More air or adding tokens is a work around for suboptimal support from the damper. 

When I put a tuned damper on the 150mm factory 36 on my trail bike I ended up 10psi lower (dropped to 78 from 88psi) as a final setting. Average travel used is the same, support is better, and small bump performance is improved also especially at slower speeds.

1
TEAMROBOT
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10/24/2025 8:12pm
It's a clever idea, but I take a little bit of issue with the claim of it being  "the only air spring capable of duplicating...

It's a clever idea, but I take a little bit of issue with the claim of it being  "the only air spring capable of duplicating a coil fork spring rate from the vary beginning to the end" when the Vorsprung Secus has been around for 5 years 

The secus needed to be outside the fork because of the limited air volume inside, so I guess the lower runt uses very low pressures and the negative coil spring is there to regain some kind of compliance after moving the piston upwards and reducing the negative spring volume. The positive chamber looks smaller, (especially with a runt installed) ie progressive so it seems a bit like robbing peter to pay paul?

The main reason I was excited about it is that Diaz managed to do something productive with the lower leg air volume on the Zeb, which I think really brings down the total performance of that chassis. This is based on my best attempt at interpreting the graphic and the copy, which is highly fallible. But yes, it looks like the coil spring on the negative chamber is a necessary evil to fit everything in there and make up for an undersized air negative chamber at full extension.

If it makes the Zeb less progressive and doesn't feel super whack at full extension, that seems like a decent trade off, to me.

2
10/25/2025 2:11pm
It's a clever idea, but I take a little bit of issue with the claim of it being  "the only air spring capable of duplicating...

It's a clever idea, but I take a little bit of issue with the claim of it being  "the only air spring capable of duplicating a coil fork spring rate from the vary beginning to the end" when the Vorsprung Secus has been around for 5 years 

The secus needed to be outside the fork because of the limited air volume inside, so I guess the lower runt uses very low pressures and the negative coil spring is there to regain some kind of compliance after moving the piston upwards and reducing the negative spring volume. The positive chamber looks smaller, (especially with a runt installed) ie progressive so it seems a bit like robbing peter to pay paul?

TEAMROBOT wrote:
The main reason I was excited about it is that Diaz managed to do something productive with the lower leg air volume on the Zeb, which...

The main reason I was excited about it is that Diaz managed to do something productive with the lower leg air volume on the Zeb, which I think really brings down the total performance of that chassis. This is based on my best attempt at interpreting the graphic and the copy, which is highly fallible. But yes, it looks like the coil spring on the negative chamber is a necessary evil to fit everything in there and make up for an undersized air negative chamber at full extension.

If it makes the Zeb less progressive and doesn't feel super whack at full extension, that seems like a decent trade off, to me.

Yeah that does seem to be whats going on, and they have provided some decent graphs which is much better than a lot of companies. I think my initial reaction has been a bit prickly since Vorsprung made a coil-like air spring a while ago now and this actually has enough unique features that it didn't need to make that claim. 

I have actually wanted air springs to feature more adjustability - major fork brands have been resistant to go fully towards a secus-like air spring curve so a design that has more fine tuning, especially in the first third of the travel could be useful in dialling in a particular feel. The current lyrik is one that just came to mind where Rockshox locked in a much more "trail" feel compared to the Zeb, but riders who want that feel of the Zeb in a shorter/lighter chassis have to compromise on some sensitivity. I think the 36 is much closer to a 38 than a lyrik is to the Zeb for comparison. 

I know my last few opinions on these air springs have been fairly negative, it just seems like companies are looking for complex solutions to solve problems when things like optimised damper tunes haven't been used to their full potential (and are plenty well understood already) 

2
bikelurker
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10/26/2025 5:33am Edited Date/Time 10/26/2025 6:06am
It's a clever idea, but I take a little bit of issue with the claim of it being  "the only air spring capable of duplicating...

It's a clever idea, but I take a little bit of issue with the claim of it being  "the only air spring capable of duplicating a coil fork spring rate from the vary beginning to the end" when the Vorsprung Secus has been around for 5 years 

The secus needed to be outside the fork because of the limited air volume inside, so I guess the lower runt uses very low pressures and the negative coil spring is there to regain some kind of compliance after moving the piston upwards and reducing the negative spring volume. The positive chamber looks smaller, (especially with a runt installed) ie progressive so it seems a bit like robbing peter to pay paul?

TEAMROBOT wrote:
The main reason I was excited about it is that Diaz managed to do something productive with the lower leg air volume on the Zeb, which...

The main reason I was excited about it is that Diaz managed to do something productive with the lower leg air volume on the Zeb, which I think really brings down the total performance of that chassis. This is based on my best attempt at interpreting the graphic and the copy, which is highly fallible. But yes, it looks like the coil spring on the negative chamber is a necessary evil to fit everything in there and make up for an undersized air negative chamber at full extension.

If it makes the Zeb less progressive and doesn't feel super whack at full extension, that seems like a decent trade off, to me.

Yeah that does seem to be whats going on, and they have provided some decent graphs which is much better than a lot of companies. I...

Yeah that does seem to be whats going on, and they have provided some decent graphs which is much better than a lot of companies. I think my initial reaction has been a bit prickly since Vorsprung made a coil-like air spring a while ago now and this actually has enough unique features that it didn't need to make that claim. 

I have actually wanted air springs to feature more adjustability - major fork brands have been resistant to go fully towards a secus-like air spring curve so a design that has more fine tuning, especially in the first third of the travel could be useful in dialling in a particular feel. The current lyrik is one that just came to mind where Rockshox locked in a much more "trail" feel compared to the Zeb, but riders who want that feel of the Zeb in a shorter/lighter chassis have to compromise on some sensitivity. I think the 36 is much closer to a 38 than a lyrik is to the Zeb for comparison. 

I know my last few opinions on these air springs have been fairly negative, it just seems like companies are looking for complex solutions to solve problems when things like optimised damper tunes haven't been used to their full potential (and are plenty well understood already) 

What can I spect from a d1 lyrik "ultimate"  (charger 3.1) (I found some very good deals around latelly, so I end up buying a Lyrik base and ultimate internals for very cheap)

For reference, I came from a '19 fox 36 performance that I really hate (it become only rideable to me after a luftkappe and some mods to the negative chamber + a different, harsh but at least supportive, comp shim stack) In stock form the fork always worked too low in its travel, and rebounded too abruptly, forcing me to run 2-3 lsr from closed, wich I am sure worsened my problems with this fork. After all the mods at least I was abble to run Lsr in the middle. I'm about 200lbs, running 95psi or so.

I'm almost sure I will end up kinda dissapointed with my new fork too ,but I just want to try a completly different stock setup from what I know, and build from there if needed

1
AndehM
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10/27/2025 10:53am

Apologies if this is too far off topic, but... asking for a friend... what's the most economical way to address overdamped rebound on a Lyrik D1 Select+ (Charger 3.0 / 27.5 / 160mm)?  Friend in question just got his 9 year old ripper a size XS Bronson 4.1 that came with that fork.  The kid is only like 80 lbs fully geared up with full body armor and DH helmet.  He races BMX and will be riding the bike at Northstar every weekend next summer.  In stock config he couldn't use more than like 90mm travel with no tokens and rebound wide open.  Friend added a Noken to it, which let him use more travel even with a few psi more, but then the kid kept wanting to add pressure to make it poppier since the rebound is already wide open, and he's back to only using like half the travel and gets worn out after 3 laps.  We're thinking we need the damper replaced or revalved with a custom extra light tune.  I can hone bushings for him and could install a 3.1 conversion kit, but don't know anything about creating a custom shim stack (the only rebound tunes RS lists in the manual for that are "regular" and "heavy").

Open to suggestions.  We're in California so the closer the better.  He'd like to not have to send in the whole fork somewhere because of shipping costs & taking the bike out of commission.  He talked to Avalanche and Craig didn't want to do anything for only the fork, only a package deal with a shock.  The bottom end of the lightest MRP Lift damper tune is about 20 lbs heavier than the kid.

1
10/27/2025 11:42am

Anti-dive device for the fork...I wonder how this rides. It has to add some harshness under braking, and I'm sure the way the bike reacts under braking would take some getting used to as well, but still an interesting experiment:

3
Primoz
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10/27/2025 11:45am

The standard and heavy tune is for LSC, rebound also comes in a light tune with the 3.1 upgrade.

2
10/27/2025 11:52am
AndehM wrote:
Apologies if this is too far off topic, but... asking for a friend... what's the most economical way to address overdamped rebound on a Lyrik D1...

Apologies if this is too far off topic, but... asking for a friend... what's the most economical way to address overdamped rebound on a Lyrik D1 Select+ (Charger 3.0 / 27.5 / 160mm)?  Friend in question just got his 9 year old ripper a size XS Bronson 4.1 that came with that fork.  The kid is only like 80 lbs fully geared up with full body armor and DH helmet.  He races BMX and will be riding the bike at Northstar every weekend next summer.  In stock config he couldn't use more than like 90mm travel with no tokens and rebound wide open.  Friend added a Noken to it, which let him use more travel even with a few psi more, but then the kid kept wanting to add pressure to make it poppier since the rebound is already wide open, and he's back to only using like half the travel and gets worn out after 3 laps.  We're thinking we need the damper replaced or revalved with a custom extra light tune.  I can hone bushings for him and could install a 3.1 conversion kit, but don't know anything about creating a custom shim stack (the only rebound tunes RS lists in the manual for that are "regular" and "heavy").

Open to suggestions.  We're in California so the closer the better.  He'd like to not have to send in the whole fork somewhere because of shipping costs & taking the bike out of commission.  He talked to Avalanche and Craig didn't want to do anything for only the fork, only a package deal with a shock.  The bottom end of the lightest MRP Lift damper tune is about 20 lbs heavier than the kid.

The new 3.1 manual includes a light rebound tune which works for 3.0 dampers as well, but I would probably remove 1 more shim than what is suggested in the stack for a kid that light

3
10/27/2025 12:00pm
iceman2058 wrote:
Anti-dive device for the fork...I wonder how this rides. It has to add some harshness under braking, and I'm sure the way the bike reacts under...

Anti-dive device for the fork...I wonder how this rides. It has to add some harshness under braking, and I'm sure the way the bike reacts under braking would take some getting used to as well, but still an interesting experiment:

When the fork dives under brakes the spring gets stiffer and you are adding harshness that way - if its dialled in well the forces should balance out enough to retain compliance rather than "resisting" the bumps. It's like the Trust forks - they were very controlled under braking and turning because they didn't load up the wheel too much or change geometry in turns which felt a little weird but actually pretty confidence inspiring. They did suffer with comfort/sensitivity but it was for different reasons and not strictly under braking

4
AndehM
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10/27/2025 1:03pm
AndehM wrote:
Apologies if this is too far off topic, but... asking for a friend... what's the most economical way to address overdamped rebound on a Lyrik D1...

Apologies if this is too far off topic, but... asking for a friend... what's the most economical way to address overdamped rebound on a Lyrik D1 Select+ (Charger 3.0 / 27.5 / 160mm)?  Friend in question just got his 9 year old ripper a size XS Bronson 4.1 that came with that fork.  The kid is only like 80 lbs fully geared up with full body armor and DH helmet.  He races BMX and will be riding the bike at Northstar every weekend next summer.  In stock config he couldn't use more than like 90mm travel with no tokens and rebound wide open.  Friend added a Noken to it, which let him use more travel even with a few psi more, but then the kid kept wanting to add pressure to make it poppier since the rebound is already wide open, and he's back to only using like half the travel and gets worn out after 3 laps.  We're thinking we need the damper replaced or revalved with a custom extra light tune.  I can hone bushings for him and could install a 3.1 conversion kit, but don't know anything about creating a custom shim stack (the only rebound tunes RS lists in the manual for that are "regular" and "heavy").

Open to suggestions.  We're in California so the closer the better.  He'd like to not have to send in the whole fork somewhere because of shipping costs & taking the bike out of commission.  He talked to Avalanche and Craig didn't want to do anything for only the fork, only a package deal with a shock.  The bottom end of the lightest MRP Lift damper tune is about 20 lbs heavier than the kid.

The new 3.1 manual includes a light rebound tune which works for 3.0 dampers as well, but I would probably remove 1 more shim than what...

The new 3.1 manual includes a light rebound tune which works for 3.0 dampers as well, but I would probably remove 1 more shim than what is suggested in the stack for a kid that light

Thanks, looking at the manual now, I must have remembered the Comp tune.  So you're suggesting taking the "Light" tune stack of 14(0.15)x3 - 7(0.3)x4 - 14(0.1)x1 (all 5mm ID) and dropping that to 14(0.15)x3 - 7(0.3)x4?  Eliminating the 14mm OD 0.1mm thick single shim?  

Don't I need to maintain the same overall stack height (1.75mm)?  If I'm doing my math right, what I could do is eliminate 2 of the 14mm 0.15 thick shims and add 1 7mm 0.3 thick spacer.

Assuming what I'm thinking about the stack height needing to remain the same, I don't see any way to reduce the Comp "Standard" tune without sourcing custom spacers.

1
10/27/2025 1:14pm
AndehM wrote:
Apologies if this is too far off topic, but... asking for a friend... what's the most economical way to address overdamped rebound on a Lyrik D1...

Apologies if this is too far off topic, but... asking for a friend... what's the most economical way to address overdamped rebound on a Lyrik D1 Select+ (Charger 3.0 / 27.5 / 160mm)?  Friend in question just got his 9 year old ripper a size XS Bronson 4.1 that came with that fork.  The kid is only like 80 lbs fully geared up with full body armor and DH helmet.  He races BMX and will be riding the bike at Northstar every weekend next summer.  In stock config he couldn't use more than like 90mm travel with no tokens and rebound wide open.  Friend added a Noken to it, which let him use more travel even with a few psi more, but then the kid kept wanting to add pressure to make it poppier since the rebound is already wide open, and he's back to only using like half the travel and gets worn out after 3 laps.  We're thinking we need the damper replaced or revalved with a custom extra light tune.  I can hone bushings for him and could install a 3.1 conversion kit, but don't know anything about creating a custom shim stack (the only rebound tunes RS lists in the manual for that are "regular" and "heavy").

Open to suggestions.  We're in California so the closer the better.  He'd like to not have to send in the whole fork somewhere because of shipping costs & taking the bike out of commission.  He talked to Avalanche and Craig didn't want to do anything for only the fork, only a package deal with a shock.  The bottom end of the lightest MRP Lift damper tune is about 20 lbs heavier than the kid.

The new 3.1 manual includes a light rebound tune which works for 3.0 dampers as well, but I would probably remove 1 more shim than what...

The new 3.1 manual includes a light rebound tune which works for 3.0 dampers as well, but I would probably remove 1 more shim than what is suggested in the stack for a kid that light

AndehM wrote:
Thanks, looking at the manual now, I must have remembered the Comp tune.  So you're suggesting taking the "Light" tune stack of 14(0.15)x3 - 7(0.3)x4 -...

Thanks, looking at the manual now, I must have remembered the Comp tune.  So you're suggesting taking the "Light" tune stack of 14(0.15)x3 - 7(0.3)x4 - 14(0.1)x1 (all 5mm ID) and dropping that to 14(0.15)x3 - 7(0.3)x4?  Eliminating the 14mm OD 0.1mm thick single shim?  

Don't I need to maintain the same overall stack height (1.75mm)?  If I'm doing my math right, what I could do is eliminate 2 of the 14mm 0.15 thick shims and add 1 7mm 0.3 thick spacer.

Assuming what I'm thinking about the stack height needing to remain the same, I don't see any way to reduce the Comp "Standard" tune without sourcing custom spacers.

The 14x0.1 is the check shim so leave that in - I would instead take the original medium tune (3 x 14mm OD shims and 2x 12mm x  0.15mm shims) and leave 1 x 14 x 0.15 and 1 x 12 x 0.15. Stack height I don't think is mega critical but it is good practice so what you can do is place the spares between spacer shims where they will do nothing ie-

Piston

14 x 0.15

12 x 0.15

7 x 0.3 - spacer

14 x 0.15

14 x 0.15

12 x 0.15

7 x 0.3 -spacer

7 x 0.3 -spacer

14 x 0.1

 

the 0.3 is thick enough that the shims will never flex far enough to touch the spares. On the compression piston, you can move a spacer shim between the face shims somewhere to reduce the preload - between the first and second reduces the compression damping to hardly anything, or moving it up in the stack retains a little bit of damping if you need it at some point. You need 1 shim in contact with the piston to maintain a seal. Or you can remove face shims and put them behind the spacers again, but I find reducing the preload is pretty effective for very light riders

4
AndehM
Posts
666
Joined
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Location
El Granada, CA US
Fantasy
10/27/2025 1:36pm

Got it, seems pretty straightforward.  Looks like a fun weekend project.  I'll probably split the difference on the compression side, putting the spacer in between #2 & #3, seeing as how I'm of the opinion some damping is better than none.  Thank you so much for your help.

1
10/27/2025 2:36pm
iceman2058 wrote:
Anti-dive device for the fork...I wonder how this rides. It has to add some harshness under braking, and I'm sure the way the bike reacts under...

Anti-dive device for the fork...I wonder how this rides. It has to add some harshness under braking, and I'm sure the way the bike reacts under braking would take some getting used to as well, but still an interesting experiment:

What is old is new again?

History repeats itself?

Those who forget the past…?


More than 40 years ago you could buy any number of sportbikes that featured anti-dive systems on the front end. They had been used on factory roadracers, then trickled down. The systems disappeared from the race bikes, then from the production bikes shortly thereafter.  Maybe an eight or nine year span altogether. In that time they learned that effective damping was better than a non-moving suspension. That and the fact that the steepened head angle helped with the turn-in once they started using Deltabox(beam type) frames that could stand the forces that slicks put into the frames. 

2
10/27/2025 3:59pm
iceman2058 wrote:
Anti-dive device for the fork...I wonder how this rides. It has to add some harshness under braking, and I'm sure the way the bike reacts under...

Anti-dive device for the fork...I wonder how this rides. It has to add some harshness under braking, and I'm sure the way the bike reacts under braking would take some getting used to as well, but still an interesting experiment:

63expert wrote:
What is old is new again?History repeats itself?Those who forget the past…?More than 40 years ago you could buy any number of sportbikes that featured anti-dive...

What is old is new again?

History repeats itself?

Those who forget the past…?


More than 40 years ago you could buy any number of sportbikes that featured anti-dive systems on the front end. They had been used on factory roadracers, then trickled down. The systems disappeared from the race bikes, then from the production bikes shortly thereafter.  Maybe an eight or nine year span altogether. In that time they learned that effective damping was better than a non-moving suspension. That and the fact that the steepened head angle helped with the turn-in once they started using Deltabox(beam type) frames that could stand the forces that slicks put into the frames. 

I was going to post a picture of a bike from the 50's in this book I have.......but realised this device only moves the mounting of the brake and the axle is still following the regular fork tubes? So I guess under brakes the torque is tying to extend the fork which is a little different to typical anti-dive geometry

2
xy9ine
Posts
29
Joined
5/1/2019
Location
ZW
10/27/2025 5:39pm
iceman2058 wrote:
Anti-dive device for the fork...I wonder how this rides. It has to add some harshness under braking, and I'm sure the way the bike reacts under...

Anti-dive device for the fork...I wonder how this rides. It has to add some harshness under braking, and I'm sure the way the bike reacts under braking would take some getting used to as well, but still an interesting experiment:

63expert wrote:
What is old is new again?History repeats itself?Those who forget the past…?More than 40 years ago you could buy any number of sportbikes that featured anti-dive...

What is old is new again?

History repeats itself?

Those who forget the past…?


More than 40 years ago you could buy any number of sportbikes that featured anti-dive systems on the front end. They had been used on factory roadracers, then trickled down. The systems disappeared from the race bikes, then from the production bikes shortly thereafter.  Maybe an eight or nine year span altogether. In that time they learned that effective damping was better than a non-moving suspension. That and the fact that the steepened head angle helped with the turn-in once they started using Deltabox(beam type) frames that could stand the forces that slicks put into the frames. 

i had an rz500 (2 stroke!) that had a rudimentary anti-dive system that was comprised of a T off the front brake line that actuated a fork compression circuit. unsurprisingly, it was not great in practice. 

3
10/27/2025 6:33pm
iceman2058 wrote:
Anti-dive device for the fork...I wonder how this rides. It has to add some harshness under braking, and I'm sure the way the bike reacts under...

Anti-dive device for the fork...I wonder how this rides. It has to add some harshness under braking, and I'm sure the way the bike reacts under braking would take some getting used to as well, but still an interesting experiment:

63expert wrote:
What is old is new again?History repeats itself?Those who forget the past…?More than 40 years ago you could buy any number of sportbikes that featured anti-dive...

What is old is new again?

History repeats itself?

Those who forget the past…?


More than 40 years ago you could buy any number of sportbikes that featured anti-dive systems on the front end. They had been used on factory roadracers, then trickled down. The systems disappeared from the race bikes, then from the production bikes shortly thereafter.  Maybe an eight or nine year span altogether. In that time they learned that effective damping was better than a non-moving suspension. That and the fact that the steepened head angle helped with the turn-in once they started using Deltabox(beam type) frames that could stand the forces that slicks put into the frames. 

xy9ine wrote:
i had an rz500 (2 stroke!) that had a rudimentary anti-dive system that was comprised of a T off the front brake line that actuated a...

i had an rz500 (2 stroke!) that had a rudimentary anti-dive system that was comprised of a T off the front brake line that actuated a fork compression circuit. unsurprisingly, it was not great in practice. 

Yep, the bikes I had with the feature were RZ500, GPz550, V45 Interceptor, and a CB1100F. Skipped street bikes for a while and just like that my 1989 FZR600 had no anti-dive. 

2
10/28/2025 9:16am

A new and improved version of Intend's Hover shock just dropped - video and full press release below:

PDF placeholder - HMC_en.pdf
S162
8
HexonJuan
Posts
396
Joined
6/10/2015
Location
WI US
10/28/2025 9:58am

OK nerds, have a live one for you. Am I nuts thinking it'd be pretty freaking sweet for sus co's to specify what their stock air spring volumes are for forks and dampers? I posit after a bit of a lengthy chat with a pal about why the X2 on his V2 Ripmo isn't the greatest choice for the platform and the bike would be better suited with a smaller spring volume, citing the playfulness of my V3 Rip. Bear in mind he's had the bike since new and never got used to the plow feel, preferring a spunkier ride. I thought it'd be sweet if we had access to that info as well as the piston diameters for those of us who like to do the math so we can better understand and show the rate change effects. 

So, silly or no?

2
1
ntm95
Posts
104
Joined
12/25/2024
Location
Lloydminster, AB CA
10/28/2025 11:29am
HexonJuan wrote:
OK nerds, have a live one for you. Am I nuts thinking it'd be pretty freaking sweet for sus co's to specify what their stock air...

OK nerds, have a live one for you. Am I nuts thinking it'd be pretty freaking sweet for sus co's to specify what their stock air spring volumes are for forks and dampers? I posit after a bit of a lengthy chat with a pal about why the X2 on his V2 Ripmo isn't the greatest choice for the platform and the bike would be better suited with a smaller spring volume, citing the playfulness of my V3 Rip. Bear in mind he's had the bike since new and never got used to the plow feel, preferring a spunkier ride. I thought it'd be sweet if we had access to that info as well as the piston diameters for those of us who like to do the math so we can better understand and show the rate change effects. 

So, silly or no?

I'd say no.

Those ratios can be calculated easily enough by a shockwiz, or anyone with a shock pump and a couple minutes.

A "spunkier" ride developed through a higher ratio air spring is typically more detrimental to descending performance as a whole. It simply makes the damping more inconsistent.

Can't say as I've ever heard of a ripmo described as a plow, the dw link is typically the opposite of that on any kind of a fast descent with square edged hits. I had a coil on mine, and it still sucked.

 

2
10/28/2025 3:58pm
iceman2058 wrote:
A new and improved version of Intend's Hover shock just dropped - video and full press release below: 

A new and improved version of Intend's Hover shock just dropped - video and full press release below:

PDF placeholder - HMC_en.pdf
S162

was silent launched earlier this month 😁

I've had it for a few solid rides now, spectacular shock!!

5

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