Mountain Bike Reviews Forum banner

Everything you need to know about the PIKE's Motion Control Damping!

16K views 107 replies 27 participants last post by  uktrailmonster 
#1 · (Edited)
Here's a Motion Control explanation guide. Even the rockshox representatives don't know this stuff. I think RS should be giving people more info about it, then they might be more inclined to consider it when they realize how great it really is...

I rode the stock spring for a week and was able to get it to not use full travel on jumps by adjusting the floodgate, it makes a huge difference. I weigh 180.

BTW, anyone who buys the PIKE should break it in good before switching to a harder spring.

Here's why the fork goes through it travel so easy even with the right spring:

The floodgate control is exactly like Marzocchi's HSCV (high speed compression valve). It remains closed until there's enough pressure to make it flip open and allow more fluid to flow. The floodgate adjuster on the PIKE allows you to change how much pressure is required to move the valve open. When you have the floodgate totally loose it requires ZERO effort to open it up so adjusting the compression knob to full closed still doesn't do anything to slow down the fork because the floodgate is overiding it and letting too much fluid through, thus no compression damping.

The floodgate valve is always working whether you have the compresion knob open or closed or anywhere in between. This is why it is considered a high speed comression valve. When you put the fork in lockout mode the compression damper is completely closed, so you are pushing entirely on the floodgate spring valve. This is why the fork maintains the ability to adjust it's SPV type lockout and the pressure reuired to move on bumpb but stay locked for no bobing. YOu have to adjust the floodgate in order to get the desired amount of lockout when the compression knob is closed.

If you are dirt jumping I would put the floodgate valve completely closed tight, that way the compression damping does it's job in slowing down the fork on hits. You then want to put the compression knob wherever you want, usually halfway.

When you hit the trails, you want to put the floodgate knob full open and the compression full open if you're not doing any drops. This will make the fork respond incredibly fast no matter what high speed you're riding at.

Pretty cool huh? The PIKE's motion control is pretty much like a fully adjustable HSCV cartrdige AND a SPV chamber in one unit, but is still more adjustable than both! I also think Motion Control feels and works better than SPV, plus it requires no air.

The idea behind that red swiss cheese thing in the PIKE's damper is this:

The compression unit and the floodgate sit at the bottom of that red thingy. The red swisscheese thing is actually a rubber spring that allows for 20mm of plush movement. This make it so that when you lock out the compression attached to the bottom of it, it still is allowed to move 20mm by compressing the rubber piece. This helps give the lockout a better transition from locked to the floodgate valve being forced open on a hit and allowing for fork movement. Very cool idea! Very simple too and light weight!

The rubber tube does a second task even when the fork isn't locked out. It allows for the compression unit to react quicker to super fast and square edged hits by allowing 20mm of movement without oil being forced through the compression/floodgate unit. This allows for the compression/floodgate enough time to open without any delay in fork compliance. It takes a micro second for the floodgate to open, but the rubber piece reacts instantly thus making it smother on REALLY fast hard square edged hits. This is similar to having a shimmed damping system like TPC. It is also why most people say it feels just as smooth or smoother at high speeds than TPC, HSCV, AND FOX's damping system.

IMO, the MOTION CONTROL SYSTEM is a very revolutionary concept to biking. You can really tell they thought outside of the box on this one. Not only did they create the most versatile damping system, it;s also lighter, more simple, and cheaper to build than any other comperable system.

VERY COOL!
 
See less See more
#2 ·
MicroHuck said:
If you are dirt jumping I would put the floodgate valve completely closed tight, that way the compression damping does it's job in slowing down the fork on hits.
Drops and jumps are low speed impacts, not high speed, so either RS is telling you the wrong thing, or the system doesn't work like you are saying.

I don't doubt the Pike's adjustments work, but if you are going to compare RSs latest product, compare it against the latest marzocchi one, which is TST. For example, my AM1 with adjustable compression blowoff, adjustable progression, lockdown, travel, air-spring, etc...
 
#3 ·
MicroHuck said:
Here's a Motion Control explanation guide. Even the rockshox representatives don't know this stuff. I think RS should be giving people more info about it, then they might be more inclined to consider it when they realize how great it really is...

I rode the stock spring for a week and was able to get it to not use full travel on jumps by adjusting the floodgate, it makes a huge difference. I weigh 180.

BTW, anyone who buys the PIKE should break it in good before switching to a harder spring.

Here's why the fork goes through it travel so easy even with the right spring:

The floodgate control is exactly like Marzocchi's HSCV (high speed compression valve). It remains closed until there's enough pressure to make it flip open and allow more fluid to flow. The floodgate adjuster on the PIKE allows you to change how much pressure is required to move the valve open. When you have the floodgate totally loose it requires ZERO effort to open it up so adjusting the compression knob to full closed still doesn't do anything to slow down the fork because the floodgate is overiding it and letting too much fluid through, thus no compression damping.

The floodgate valve is always working whether you have the compresion knob open or closed or anywhere in between. This is why it is considered a high speed comression valve. When you put the fork in lockout mode the compression damper is completely closed, so you are pushing entirely on the floodgate spring valve. This is why the fork maintains the ability to adjust it's SPV type lockout and the pressure reuired to move on bumpb but stay locked for no bobing. YOu have to adjust the floodgate in order to get the desired amount of lockout when the compression knob is closed.

If you are dirt jumping I would put the floodgate valve completely closed tight, that way the compression damping does it's job in slowing down the fork on hits. You then want to put the compression knob wherever you want, usually halfway.

When you hit the trails, you want to put the floodgate knob full open and the compression full open if you're not doing any drops. This will make the fork respond incredibly fast no matter what high speed you're riding at.

Pretty cool huh? The PIKE's motion control is pretty much like a fully adjustable HSCV cartrdige AND a SPV chamber in one unit, but is still more adjustable than both! I also think Motion Control feels and works better than SPV, plus it requires no air.

The idea behind that red swiss cheese thing in the PIKE's damper is this:

The compression unit and the floodgate sit at the bottom of that red thingy. The red swisscheese thing is actually a rubber spring that allows for 20mm of plush movement. This make it so that when you lock out the compression attached to the bottom of it, it still is allowed to move 20mm by compressing the rubber piece. This helps give the lockout a better transition from locked to the floodgate valve being forced open on a hit and allowing for fork movement. Very cool idea! Very simple too and light weight!

The rubber tube does a second task even when the fork isn't locked out. It allows for the compression unit to react quicker to super fast and square edged hits by allowing 20mm of movement without oil being forced through the compression/floodgate unit. This allows for the compression/floodgate enough time to open without any delay in fork compliance. It takes a micro second for the floodgate to open, but the rubber piece reacts instantly thus making it smother on REALLY fast hard square edged hits. This is similar to having a shimmed damping system like TPC. It is also why most people say it feels just as smooth or smoother at high speeds than TPC, HSCV, AND FOX's damping system.

IMO, the MOTION CONTROL SYSTEM is a very revolutionary concept to biking. You can really tell they thought outside of the box on this one. Not only did they create the most versatile damping system, it;s also lighter, more simple, and cheaper to build than any other comperable system.

VERY COOL!
Thanks. All the info I can get on this fork is helpful. It may be the ticket for me and my Heckler. Until now the Fox 36 seemed like what I really wanted, but the price rules it out for at least another season. This could actually work out.

Where is all this info from if not from Rock Shox?

Kapusta
 
#4 ·
Good info. I have had the Pike Team version for a couple of months now. I agree that it is a very functional and adjustable fork. I didn't know that the floodgate also functioned when the lockout wasn't activated. Only realy complaint that I have is that it doesn't have an air or spring preload adjustment to fine tune the sag/spring to my weight. I am also curious where the info is comming from if not RS.
 
#5 ·
So ... Correct me if I am wrong ?

I can adjust the floodgate setting to minimise bob , with a compression setting to stop me bottoming out on drops and jumps ,
I can then run the fork fully open for trail riding but when i see a jump/drop/climb , I can lock it out. and have the compression and floodgate take over to control the landing or 0 bob in the climb ?
 
#6 ·
DH_WP said:
I can adjust the floodgate setting to minimise bob , with a compression setting to stop me bottoming out on drops and jumps ,
I can then run the fork fully open for trail riding but when i see a jump/drop/climb , I can lock it out. and have the compression and floodgate take over to control the landing or 0 bob in the climb ?
yep, pretty much it, in a nutshell.

i've got a team version, and it works as advertised. though i've rarely used the compression/floodgate stuff other than on a few climbs and some urban so far, it has been great when i have. time will tell; most of the high up, long climbing stuff for me is still wet/snowy.....

the range of adjustment is pretty wide. so even if you need a little heavier spring, you can run it stiffer with the FG/compression stuff until you can get a new coil in there. a bit of air preload would be nice, but not really needed.
 
#7 ·
There is no way that the red swiss cheese looking thing is moving 20mm. It is not rubber. It is a 5000 inch/pound plastic spring. You are correct in that the valve is forced open by a hit, but the space between the valve at the bottom and the rod to activate it is very, very small. They used plactic because it doesn't have to compress much (5000 inch/pound is VERY stiff) to activate. The red spring isn't used to absorb any bumps at all.

I agree that it is light and ingenious. Very simple and very effective.

-James

MicroHuck said:
The idea behind that red swiss cheese thing in the PIKE's damper is this:

The compression unit and the floodgate sit at the bottom of that red thingy. The red swisscheese thing is actually a rubber spring that allows for 20mm of plush movement. This make it so that when you lock out the compression attached to the bottom of it, it still is allowed to move 20mm by compressing the rubber piece. This helps give the lockout a better transition from locked to the floodgate valve being forced open on a hit and allowing for fork movement. Very cool idea! Very simple too and light weight!

The rubber tube does a second task even when the fork isn't locked out. It allows for the compression unit to react quicker to super fast and square edged hits by allowing 20mm of movement without oil being forced through the compression/floodgate unit. This allows for the compression/floodgate enough time to open without any delay in fork compliance. It takes a micro second for the floodgate to open, but the rubber piece reacts instantly thus making it smother on REALLY fast hard square edged hits. This is similar to having a shimmed damping system like TPC. It is also why most people say it feels just as smooth or smoother at high speeds than TPC, HSCV, AND FOX's damping system.
 
#9 · (Edited)
James@GearReview said:
There is no way that the red swiss cheese looking thing is moving 20mm. It is not rubber. It is a 5000 inch/pound plastic spring. You are correct in that the valve is forced open by a hit, but the space between the valve at the bottom and the rod to activate it is very, very small. They used plactic because it doesn't have to compress much (5000 inch/pound is VERY stiff) to activate. The red spring isn't used to absorb any bumps at all.

I agree that it is light and ingenious. Very simple and very effective.

-James
Sorry dude...

YOU ARE SOOOOOOOOO WRONG!

I suggest you check out www.the-red-pill.com click on PIKE then "forks in action" then click on the video "Motion Control". You will see video of how the spring tube is specificly used for small bump compliance when the fork is locked out, this also equates to a buffer zone for compression damping when the fork isn't locked..

The plastic/rubber swiss cheese piece is actually very pliable for the first 15-20mm and then ramps up to full out stiff 1mm after that. Try putting the floodgate to full lock and then putting the compression to full lock. You will notice that the fork will go down 20mm+ very easily and then stop, this is the conpression spring tube doing it's thing. Want proof? here ya go, it's all in the pics, in fact I'm showing closer to 23mm of movement.

JM- I don't know what the heck your problem is. Please try understanding what Motion control does before trying to pretend you know anything about it. You know a lot about MArzocchi, but nothing about RS Motion control. The floodgate has everything to do with how the fork behaves on jumps. See... if you have the floodgate full open and try slowing down the fork on drops with just the compression knob, you won't accomplish anything. This is because the floodgate opens up when the compression get's ANY pressure and bypasses the compression valving, thus no compression damping on large hits. You have to close the floodgate all the way or considerably in order to prevent it from bypassing the compression unit. Pretty simple to understand. That's why you have people asking why their brand new PIke doesn't respond to the damping control, because it comes stock with the floodgate wide open.

Do you understand what low speed and highspeed compression damping actually means?
Basicly, the low speed valve is just an adjustable port (can change size of port). The highspeed valve (floodgate) is a spring loaded valve that is forced open when fluid pressures are too great for the ported compression hole. You can adjust how firm the springload is on the floodgate valve, thus changing how the fork reacts to high speed hits.

When the compression hole is closed (just turn knob 180 degrees) the floodgate valve is forced to take the task of letting fluid through. Since it has a spring loaded tension in it, it requires a certain amount of pressure to push the valve open. You can adjust how much pressure it takes to break the valve open and get regular travel, just like SPV.

Every adjustment on the PIKE goes from nothing to everything, meaning full range of user adjustment. Just like the AM-1 TST system, you can set it up so that the compression knob is EXACTLY like the TST knob. Put it full open and get no comrpession damping, turn it half way and get good low speed compression damping, turn in half a turn from open and it's closed out and in Stable Platform mode. The thing that I like about Motion Control over TST, is that you can fine tune how the fork reacts in all of the compression settings, you can't do that with TST without changing oil (which is not practical on the trailside).
 

Attachments

#10 ·
MicroHuck said:
Do you understand what low speed and highspeed compression damping actually means?
Yes, but you don't understand that drops and jumps are low speed impacts, and that rock gardens and roots are high speed, regardless of the actual speed of the bike.
 
#11 ·
Jm. said:
Yes, but you don't understand that drops and jumps are low speed impacts, and that rock gardens and roots are high speed, regardless of the actual speed of the bike.
??

jumps, drops (ie, hucking) are high-speed impacts (at least in regards to SPV/motion control) b/c the fork is moving at a high rate of speed. pedaling, braking, turns, g-outs, etc are considered low-speed impacts b/c the force on the fork is more gradual. so dirt jumps/drops/etc *will* activate the floodgate. haven't had any time on TST, but motion control is sweet.
 
#12 ·
Jm. said:
Yes, but you don't understand that drops and jumps are low speed impacts, and that rock gardens and roots are high speed, regardless of the actual speed of the bike.
JM- we're not talking about 6 inch drops here...

Since when is a 4ft+ drop slow speed? You are very confused about what damping means.

Damping is the fluid controlled resistance to fork movement. How can there be ANY compression damping if there is no resistance to movement? If the compression is set closed to resist movement then that equals pressure no matter how fast of a hit, thus any pressure is going to flip open the floodgate if it set really loose.

The thing is, you don't even seem to know what the floodgate IS. It can be set to be full loose and require NO pressure to activate it to open, THUS at that point it is a low speed compression valve TOO! You have to turn up the floodgate and tighten it in order for it to only actuate on high speed hits.

I guess you could call it BOTH a low speed valve AND a high speed valve. You can even set it so that it NEVER opens which is good for big drops.

JM you are starting to make me laugh every time you post in my threads. You give nothing to help people understand the topic and just keep dishing out the same stuff.. "the AM-1 does this... the AM-1q does that...". How does that help people trying to understand motioncontrol? Plus you are completely oblivious to how "adjustable" motion control works.
 
#14 ·
MicroHuck said:
Am I the ONLY one on this forum who knows how motion control works?

So far it's just been a lot of people with no clue just making false assumptions without experiencing it first hand...
Well, you have been asked several times in this thread where you are getting your info from, and I am still curious to know. It is not from the web site, and you claim that reps don't know this, so how do you? I watched the clip you are talking about, and it does cover in broad terms the functions you describe, (and confirms your asssertion that the swiss cheese thingy is a sort of spring) though many of your finer details are not mentioned there, such as the floodgate control doing anything when in the "unlocked" mode.

I am not trying to disagree with you, it's just that it would be good to know whether this is based on knowledge of the design or if it is your interpretation of your experience with the shock. In other words, is what you are saying regarding the floodgate control based soley on your playing around with it? (which would be equally, if not more, valid BTW)

Kapusta
 
#15 · (Edited)
kapusta said:
Well, you have been asked several times in this thread where you are getting your info from, and I am still curious to know. It is not from the web site, and you claim that reps don't know this, so how do you? I watched the clip you are talking about, and it does cover in broad terms the functions you describe, (and confirms your asssertion that the swiss cheese thingy is a sort of spring) though many of your finer details are not mentioned there, such as the floodgate control doing anything when in the "unlocked" mode.

I am not trying to disagree with you, it's just that it would be good to know whether this is based on knowledge of the design or if it is your interpretation of your experience with the shock. In other words, is what you are saying regarding the floodgate control based soley on your playing around with it? (which would be equally, if not more, valid BTW)

Kapusta
I've talked with Angry Asian on this issue. He went directly to the guys who designed the fork for the info on the floodgate valve.

The rest of my info is from just experimenting with the adjustments extensively.

Most of the info that RS provides doesn't tell you the whole story of how it works. Even if you ask their public representatives at gear shows, they don't really understand more than what's written in brochures.

IMO, RS has failed misserably in informing people of what their fork does and how it does it. That's why I'm here trying to help people understand it fully.

I'm surprised no RockShox employees are on here helping people out. Everyone seems to think I work for them. The fact is, would a RS employee admit to smoking weed? I also live in washington.

I just noticed that there's TONS of wrong info floating around about Motion Control, like thinking the swisscheese tube isn't there for bumps (that's the only reason it's there). I know the truth so I feel obligated to inform people of it.

Hope I've been helpfull! Not many people thank me. Instead I just get hate PMs from people calling me a RS employee or saying I'm stupid for thinking a Rcckshox product actually outperforms and out adjusts EVERY other system out there...
 
#16 ·
I am not sure where you are getting the 23mm of movement, though I agree that you are getting it, I am just not sure what is allowing it. I handled the plastic spring at InterBike and find it hard to believe that it would move that much. Besides, plastic doesn't like to bend that much. The only way that they can get away with using it the way that they do is if it doesn't move that much. Plastic fatigues fairly quickly is that kind of situation. Not the best medium for a spring that has to move a fair amount. I am not commenting on Motion Control, or the lockout. I am only stating that the red plastic spring does NOT move 20mm. Is there another spring in there to allow for that movement? More than likely. Again, does the fork move locked out? Yes, your picture clearly shows that, is it the plastic spring allowing that movement? No way.

-James

MicroHuck said:
Sorry dude...

YOU ARE SOOOOOOOOO WRONG!

I suggest you check out www.the-red-pill.com click on PIKE then "forks in action" then click on the video "Motion Control". You will see video of how the spring tube is specificly used for small bump compliance when the fork is locked out, this also equates to a buffer zone for compression damping when the fork isn't locked..

The plastic/rubber swiss cheese piece is actually very pliable for the first 15-20mm and then ramps up to full out stiff 1mm after that. Try putting the floodgate to full lock and then putting the compression to full lock. You will notice that the fork will go down 20mm+ very easily and then stop, this is the conpression spring tube doing it's thing. Want proof? here ya go, it's all in the pics, in fact I'm showing closer to 23mm of movement.

JM- I don't know what the heck your problem is. Please try understanding what Motion control does before trying to pretend you know anything about it. You know a lot about MArzocchi, but nothing about RS Motion control. The floodgate has everything to do with how the fork behaves on jumps. See... if you have the floodgate full open and try slowing down the fork on drops with just the compression knob, you won't accomplish anything. This is because the floodgate opens up when the compression get's ANY pressure and bypasses the compression valving, thus no compression damping on large hits. You have to close the floodgate all the way or considerably in order to prevent it from bypassing the compression unit. Pretty simple to understand. That's why you have people asking why their brand new PIke doesn't respond to the damping control, because it comes stock with the floodgate wide open.

Do you understand what low speed and highspeed compression damping actually means?
Basicly, the low speed valve is just an adjustable port (can change size of port). The highspeed valve (floodgate) is a spring loaded valve that is forced open when fluid pressures are too great for the ported compression hole. You can adjust how firm the springload is on the floodgate valve, thus changing how the fork reacts to high speed hits.

When the compression hole is closed (just turn knob 180 degrees) the floodgate valve is forced to take the task of letting fluid through. Since it has a spring loaded tension in it, it requires a certain amount of pressure to push the valve open. You can adjust how much pressure it takes to break the valve open and get regular travel, just like SPV.

Every adjustment on the PIKE goes from nothing to everything, meaning full range of user adjustment. Just like the AM-1 TST system, you can set it up so that the compression knob is EXACTLY like the TST knob. Put it full open and get no comrpession damping, turn it half way and get good low speed compression damping, turn in half a turn from open and it's closed out and in Stable Platform mode. The thing that I like about Motion Control over TST, is that you can fine tune how the fork reacts in all of the compression settings, you can't do that with TST without changing oil (which is not practical on the trailside).
 
#17 ·
James@GearReview said:
I am not sure where you are getting the 23mm of movement, though I agree that you are getting it, I am just not sure what is allowing it. I handled the plastic spring at InterBike and find it hard to believe that it would move that much. Besides, plastic doesn't like to bend that much. The only way that they can get away with using it the way that they do is if it doesn't move that much. Plastic fatigues fairly quickly is that kind of situation. Not the best medium for a spring that has to move a fair amount. I am not commenting on Motion Control, or the lockout. I am only stating that the red plastic spring does NOT move 20mm. Is there another spring in there to allow for that movement? More than likely. Again, does the fork move locked out? Yes, your picture clearly shows that, is it the plastic spring allowing that movement? No way.

-James
I understand what you're saying. There must be something else giving the movement right?

Not really. When the compression isn't locked out the first two inches of travel are VERY plush and don't require much force at all to push it down. When I put the compression and floodgate to full locked is stiffnes up a bit, thus telling me that the compression unit is blocking oil. Since the compression unit isn't allowing any fluid to flow AND it's located at the bottom of the spring tube, there's only one place you can get movement. That being the MC spring tube. Why would RS put that in there if it wasn't designed to take any movement? They even state that that is exactly why it's there, to give "some" small bump compliance when locked out and to make for a nice transition in the platform breaking loose.

Next time I open my fork for an oil change, I will document how much the spring tube actually bends to pressure. That's the only true way to tell, but from my deductive observations, the MC spring tube does allow for up to 20mm of travel. After that though the MC unit turns full out rigid and doesn't move.

I think that is why they made it with swisscheese looking holes. Those holes allow for a specific amount of movement. When the thing compresses to a certain point, those holes close up and thus no more compliance. Makes sense if you think about it...
 
#19 ·
MicroHuck, I have held the spring tube. It doesn't move that much. I have tried to compress it while it was out of the fork. I can tell you exactly what it does. It is the spring that keeps the floodgate from activating all the time. I don't have pictures so I know that I am not making myself clear. There is a rod from the valve and a rod from the adjuster. These two rods don't meet. How much they don't meet is up to the adjuster. When a bump is hit with sufficient force, the spring tube deflects a very small amount and the rods meet, forcing the valve open. Elegantly simple and very effective. Please, do take a look at it when you have it apart next. It is very simple and very well engineered. If only they made one without a through axle.

-James

one more thing, I believe that the spring is in the other leg. There aren't springs in both legs.

MicroHuck said:
I understand what you're saying. There must be something else giving the movement right?

Not really. When the compression isn't locked out the first two inches of travel are VERY plush and don't require much force at all to push it down. When I put the compression and floodgate to full locked is stiffnes up a bit, thus telling me that the compression unit is blocking oil. Since the compression unit isn't allowing any fluid to flow AND it's located at the bottom of the spring tube, there's only one place you can get movement. That being the MC spring tube. Why would RS put that in there if it wasn't designed to take any movement? They even state that that is exactly why it's there, to give "some" small bump compliance when locked out and to make for a nice transition in the platform breaking loose.

Next time I open my fork for an oil change, I will document how much the spring tube actually bends to pressure. That's the only true way to tell, but from my deductive observations, the MC spring tube does allow for up to 20mm of travel. After that though the MC unit turns full out rigid and doesn't move.

I think that is why they made it with swisscheese looking holes. Those holes allow for a specific amount of movement. When the thing compresses to a certain point, those holes close up and thus no more compliance. Makes sense if you think about it...
 
#20 ·
James@GearReview said:
MicroHuck, I have held the spring tube. It doesn't move that much. I have tried to compress it while it was out of the fork. I can tell you exactly what it does. It is the spring that keeps the floodgate from activating all the time. I don't have pictures so I know that I am not making myself clear. There is a rod from the valve and a rod from the adjuster. These two rods don't meet. How much they don't meet is up to the adjuster. When a bump is hit with sufficient force, the spring tube deflects a very small amount and the rods meet, forcing the valve open. Elegantly simple and very effective. Please, do take a look at it when you have it apart next. It is very simple and very well engineered. If only they made one without a through axle.

-James

one more thing, I believe that the spring is in the other leg. There aren't springs in both legs.
OK, I'll give you that. One thing I don't get though.

Have your ever had a fork spring in your hand? It's pretty much impossible to compress a fork spring by hand, yet can feel very plush when you put it into a fork and lean on it.

There's a HUGE difference between arm strength and 180 lbs of body weight. I would agree with you on one thing, the plastic tube must be hard to bend with just your hands (just like a coil spring).

I'm still interested in where that 20mm is coming from, so I guess I'll just have to wait and check it out next time I open the fork.

Regardless of your own personal oberservations, rockshox claims that the spring tube was placed into there for small bumps when locked out. How else would they achieve 20mm of compliance when the fork is locked? That's what I want to know...
 
#21 ·
The 20 mm has to come from another spring. I don't have a cut away with me of the fork. I'll go through my literature this evening (i don't have it with me) and see if I can answer some of your questions.

Yes, I have tried to compress a coil spring outside of a fork. You are correct that it is hard. I have tried to compress an MCU stack, and that, too, was very hard. This is a whole different level. I don't have a Pike in my possession. In fact, InterBike was the last time I saw one. I just know that the plastic spring is NOT the main spring.

The reason they might claim that it is for small bump compliance (warning: I am moving into the relm of speculation here so take it with a grain of salt) is that it allows Rock Shox to separate small hit compliance from the big hits. The plastic spring would only activate on big hits (how big depends on the settings), but another system, with other settings, would be active on the small stuff.

Again, I will try and dig up a cut-away of the fork. I really am not trying to be confusing, but I don't have an image at hand that shows what I am trying to say.

-James

MicroHuck said:
OK, I'll give you that. One thing I don't get though.

Have your ever had a fork spring in your hand? It's pretty much impossible to compress a fork spring by hand, yet can feel very plush when you put it into a fork and lean on it.

There's a HUGE difference between arm strength and 180 lbs of body weight. I would agree with you on one thing, the plastic tube must be hard to bend with just your hands (just like a coil spring).

I'm still interested in where that 20mm is coming from, so I guess I'll just have to wait and check it out next time I open the fork.

Regardless of your own personal oberservations, rockshox claims that the spring tube was placed into there for small bumps when locked out. How else would they achieve 20mm of compliance when the fork is locked? That's what I want to know...
 
#22 · (Edited)
MicroHuck said:
JM- we're not talking about 6 inch drops here...

Since when is a 4ft+ drop slow speed? .
Since the speed of the fork moving up and down was relatively slower on a drop or jump as compared to when you ride through an impact and the fork has to move up and down faster, which would be a root or rock.

You seem to have a general lack of knowledge in this area. You should stop while you are behind.
 
#23 ·
Jm. said:
Since the speed of the fork moving up and down was relatively slower to when you ride through an impact and the fork has to move up and down faster.

You seem to have a general lack of knowledge in this area. IYou should stop while you are behind.
Doesn't this guy annoy the phuck outta you? He thinks he knows everything, yet lacks some very basic knowledge.

-TS
 
#24 ·
Hey JM, i'm in agreement with everyone else here. High speed dampening refers to how fast the fork or shock blows through its travel. The impact caused from a 4 ft drop causes the fork to go through the majority of its travel very fast. I think where your confused is when thinking about how quickly the fork prepares it's self for the next hit. This has nothing to do with High or Slow speed dampening this refers to the rebound dampening causing the fork to follow the contours of a trail.

In the end:

Big hit = High Speed Dampening (blows through travel at a HIGHSPEED)
Small bumps = Slow Speed Dampening (go's through travel at a SLOW SPEED)
 
#25 ·
drum714 said:
Hey JM, i'm in agreement with everyone else here. High speed dampening refers to how fast the fork or shock blows through its travel. The impact caused from a 4 ft drop causes the fork to go through the majority of its travel very fast. I think where your confused is when thinking about how quickly the fork prepares it's self for the next hit. This has nothing to do with High or Slow speed dampening this refers to the rebound dampening causing the fork to follow the contours of a trail.

In the end:

Big hit = High Speed Dampening (blows through travel at a HIGHSPEED)
Small bumps = Slow Speed Dampening (go's through travel at a SLOW SPEED)
Then you are only in agreement with one person.

The impact from a 4 ft drop causes the fork to go through it's travel much slower compared to how fast the fork has to move when you hit a rock or root out on the trail.

This has everything to do with the high and low speed damping.

Sorry.
 
#26 · (Edited)
Enough already!!!!!!

Ok, here's the deal with the spring tube: Yes, even without allowing oil through the piston, it DOES allow for about 20mm of fork movement. You are all forgetting that 20mm of fork movement does NOT equal a 20mm change in oil height. As the fork moves through its travel, the damper shaft enters into the oil chamber, shrinking the internal volume of that chamber which causes the fluid level to rise. However, the damper shaft has a much smaller diameter than the oil chamber (and hence, a fairly small volume), so 20mm of damper shaft movement only raises the oil level by maybe about 1/4 of that (I'd have to measure the OD of the shaft vs. the ID of the chamber to be sure).

Microhuck: I can appreciate your enthusiasm for RS' Motion Control setup (it really is quite slick), but you've got some details mixed up a little bit. I don't remember this conversation specifically (sorry, I get A LOT of emails), but while we might have talked about 20mm of movement while the fork was locked out, I certainly never said that the spring tube itself moved that much. Think about it; that thing is made of fairly rigid plastic. While it is designed to be a "spring" to a certain extent, that much strain would certainly result in at least SOME permanent deformation.

Anyway, I'm not even going to get involved in this low-speed vs. high-speed argument!

www.angryasian.com
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top