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Discussion Starter · #1 ·
It seems the two systems have smart lock-out and ability to eat bumps automatically.
Can anyone here please point out their difference and comment on each system?
Thx for advice.
 

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Theoretically, the terralogic will give you better suspension performance and resist pedaling/downward forces better. Psychologically I don't know if I could get used to it due to the fact that there is something keeping the fork from compressing from downward inputs, even though there is some kind of blowoff. SPV creates a platform where any force above the threshold that you set will activate the suspension. It will resist movement to anything below that threshold, so it will loose some sensitivity and suspension action, even if it is just minimal. The fox has an "inertia valve" which is a spring loaded brass valve that keeps any downward force from compressing the suspension, upward forces like bumps or little dropoffs will displace the brass valve and allow the suspension to work.
 

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Jm. said:
Theoretically, the terralogic will give you better suspension performance and resist pedaling/downward forces better. Psychologically I don't know if I could get used to it due to the fact that there is something keeping the fork from compressing from downward inputs, even though there is some kind of blowoff. SPV creates a platform where any force above the threshold that you set will activate the suspension. It will resist movement to anything below that threshold, so it will loose some sensitivity and suspension action, even if it is just minimal. The fox has an "inertia valve" which is a spring loaded brass valve that keeps any downward force from compressing the suspension, upward forces like bumps or little dropoffs will displace the brass valve and allow the suspension to work.
I'd like to add to your great discription of the terralogic Fox fork. Another way to describe what an inertia valve does is that it allows the shock to differenciate between a chassis input and a wheel input. Obviously the chassis needs a lot more resistance to movement @ low velocities than the wheel needs. With an inertia valve you can tune 1 circuit for pedaling resistance (allow for sag) and tune the separate wheel circuit for maximum comfort. Then you let the inertia valve switch to the right circuit @ the right time. There's a difference in the way Stratos Inertial Valve works in that in has a hydraulic acceleration chamber to make sure the transition is seamless(magical). I've read some comments about other inertia valve shocks having worn parts. If the inertia valve is designed right they should go at least 1 million cycles with no wear. I was responsible for the inertia valve shocks used by Citreon to dominate the Paris/Dakar Rallye. Those shocks would be rebuilt after 6000 kms, the inertia valves showed no wear and were not replaced. We never had any stuck valves either. I hope this helps.
 

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SPV comments..

An SPV fork is not really anything like an "automatic lockout"

Tech-speak aside, what it effectively does is reduce bob during seated climbing. When you stand up and hammer, it doesnt have much of an effect (unless you have the pressure so high as to reduce small-bump sensitivity.

On the flip side, it does a pretty good job on technical stuff by remaining active and not fully locked out, which eliminates the sag and makes the fork ride taller. (One reason I rarely used the lockout on my old SID -- the extra height made the front wheel light on steep climbs)
 

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Shocknerd said:
I'd like to add to your great discription of the terralogic Fox fork. Another way to describe what an inertia valve does is that it allows the shock to differenciate between a chassis input and a wheel input. Obviously the chassis needs a lot more resistance to movement @ low velocities than the wheel needs. With an inertia valve you can tune 1 circuit for pedaling resistance (allow for sag) and tune the separate wheel circuit for maximum comfort. Then you let the inertia valve switch to the right circuit @ the right time. There's a difference in the way Stratos Inertial Valve works in that in has a hydraulic acceleration chamber to make sure the transition is seamless(magical). I've read some comments about other inertia valve shocks having worn parts. If the inertia valve is designed right they should go at least 1 million cycles with no wear. I was responsible for the inertia valve shocks used by Citreon to dominate the Paris/Dakar Rallye. Those shocks would be rebuilt after 6000 kms, the inertia valves showed no wear and were not replaced. We never had any stuck valves either. I hope this helps.
I was wondering if you have had any experience with a Stratos ID equipped fork. It sounds interesting and MBA gave it a glowing report but I always cautious of vested interests. I previously had a Fox F100X and thought it was great. I'm now useing a 130mm. SPV (Minute 3:00) and as stated elsewhere only works while seated. It still bobs like a cork when standing which I think is accentuated by the stable VPP on the back of my bike. All movement during hard pedalling is transfered to the fork. It seems to me that Manitou obviously didn't get it right the first time as the innards of 2005 SPV forks are substantially changed.

If the Stratos cartridge really works and is reliable, it would be possible to make a great long travel fork with one. I've been thinking in terms of a Fox Float 130 R refitted and it would be cheaper than a F100X.
 

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Ronnie said:
I was wondering if you have had any experience with a Stratos ID equipped fork. It sounds interesting and MBA gave it a glowing report but I always cautious of vested interests. I previously had a Fox F100X and thought it was great. I'm now useing a 130mm. SPV (Minute 3:00) and as stated elsewhere only works while seated. It still bobs like a cork when standing which I think is accentuated by the stable VPP on the back of my bike. All movement during hard pedalling is transfered to the fork. It seems to me that Manitou obviously didn't get it right the first time as the innards of 2005 SPV forks are substantially changed.

If the Stratos cartridge really works and is reliable, it would be possible to make a great long travel fork with one. I've been thinking in terms of a Fox Float 130 R refitted and it would be cheaper than a F100X.
I called Stratos and they said yes, they do have an ID cartridge for a Fox Float 130 R. RE: the vested interest question the answer is also yes. I licensed Stratos. I hope you get an ID and please let me know what you think of it.
 
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