Yea from what I read it takes some effort to dial in but it'll pay off
Another fork choice, Cane Creek joins the game
- Thread starter Metamorphic
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- coil boingers
Follow up - got any info on the 10mm travel loss you described?
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As far as spring ramp up, here's a quote from a colleague who has spent 30 years doing race car damper engineering: at best the damper is icing on the cake, the spring should be doing most of the work.
So, get your spring to do what you want first, then the damper is mainly there for vibration attenuation and fine tuning.
So, get your spring to do what you want first, then the damper is mainly there for vibration attenuation and fine tuning.
I don't know about that, I follow automotive stuff pretty closely. Good damper setups (coil overs, even just aftermarket struts) are way way better than OEM, and the magnetic suspension from GM has catapulted it to the next level for OEM vehicles, allowing cars like the ZL-1, 1LE, Corvettes and others to hold the road better than cars without the same, while providing a more compliant ride. Sure, springs are part of this too, but to say the damper doesn't really matter much is pretty ridiculous. HUGE performance difference based on dampers.
Auto racing, is done on a pretty smooth track. And yes the spring does the work, and a good shock for rebound control (I did not even use antI sway bars) this is almost all low speed compression. High speed hits can make the car loose and out of control.
MTB you want the suspension to react differently in different situations. You're going to need the dampener to help with this.
The magnetic control on the corvette is similar since your trying to get race performance in a real road situation with bumps and such, not the best on smooth tracks.
MTB you want the suspension to react differently in different situations. You're going to need the dampener to help with this.
The magnetic control on the corvette is similar since your trying to get race performance in a real road situation with bumps and such, not the best on smooth tracks.
I didn't say dampers are useless or can't make a difference. But the spring is/should be doing most of the work, and it's best to get that dialed first. Then the damper tuning is the icing on the cake.
And, a dampener is what you use to wash the mud off you bike after you're done riding. That has nothing to do with suspension.
And, a dampener is what you use to wash the mud off you bike after you're done riding. That has nothing to do with suspension.
^^
Alternative faxxx. Apparently Mr. Science Guy isn't aware that Huck Norris is making oil soaked rags that you milk into your fork after you remove your stupid damper cart. The rags offer a meaningful weight savings, are easily tuneable (just remove or add rags to change performance characteristics) , have a much longer service interval than a standard cartridge and help keep your bushings, well, damp.
The dampening rags are only $99.99, and you get a free wok if you order now.
this is why when setting up suspension you start with the sping, and set sag with all damping turned off. then add damping as required.
Yes the correct term is damper, dampener is excepted but not proper.
There are many schools of thought when it comes to suspension. In autoracing there is the idea you used, and the idea of the springs only suport the vehicle weight when static. The use of compression in the shocks/struts and sway bars are used. This is how street cars are done so you get a nicer ride. But it effects mecanical grip.
I'll give you that the spring should do most the work (60%) but compared to auto racing it's much higher when using this idea. (I say idea because suspension is as much art as it is math, many people win using different ideas)
IMHO In an offroad environment if the spring did most the work you would be using it for chassis balance, the spring rate would be too high, causing you to bounce off objects.
If we use low speed compression to control chassis movement it allows the suspension to track and have better grip.
But that actually does not matter, does it? The damping will alter the path to equilibrium (i.e. how many & how big oscillations it is going to take to reach it), but eventually, only the spring setting matters for sag. And internal stiction.
I'm no expert, but my understanding is that lsc will provide enough resistance to movement as to skew the sag setting. Like I said, I'm no expert, and I get what you're saying, but in practice, I've noticed the difference. With no damping, the shock moves more freely, and seems to be more sensitive. Maybe it's just a question of finding that sweet spot quicker?
it shouldn't. damping (shouldn't) affect the displacement of the suspension component in travel, just affect the rate (speed) at which that displacement occurs.
We're in agreement, the spring does most of the work, and the damper is for fine tuning. This answers the original question of "why does this new Cane Creek fork have an adjustable air volume for the spring?"
And, of course suspension tuning is a never ending iterative process. That's why F1 teams still have a gang of engineers ready to adjust everything each time the car goes on track.
i can't believe our resident former f1 expert and current suspension guru has not chimed in yet...
I'll respectfully say that's a gross oversimplification at best.
The spring and damper work together, they are just as important as each other.
Damping certainly isn't just there for "vibration attentuation and fine tuning", it (rebound damping particularly) plays a huge role in chassis stability and predictability which are key performance factors in any two or four-wheeled vehicle. Certainly yes, get the spring rate right first. I think most people here already know that though.
Cerberus75 is correct in his post, and to be honest I don't really think it's "in agreement" with what you suggested originally.
This (desire for increased fork progression) is a thing because air springs are nonlinear, even with the latest designs. Given the higher rate earlier in the travel (when comparing an air spring's averaged rate to a coil spring's ~constant rate), there's a tendency for people to reduce the average spring rate (i.e. less pressure) in an attempt to reduce the higher initial rate and increased breakway/friction forces - which is fair. The air spring rate also falls to some extent in the middle of the stroke before increasing again.
The net result is that more travel is used than is ideal in most scenarios, so you need to increase spring force at the end of the travel (and/or compression damping force/s) to avoid bottoming out or blowing too deep into the travel. In my experience air forks always require more compression damping to maintain a given level of stability due to the spring curve.
In a correctly sprung and damped coil fork there isn't a huge need for spring rate progression in my opinion, but certainly even if some is desired (I think personal preference can apply here), the amount would be less than on an air fork due to the linear spring curve and resultant increase in travel usage efficiency for a given level of bump absorption.
To extend a little further (if anyone is interested) - it's also important to remember that the front and rear of an MTB (particularly for DH) have slightly different requirements - which is exactly why you can't just assume progressive curve good for rear = progressive curve good for front. The reduced rate in the first ~1/3 of the curve can be effective for improving bump absorption on the rear of a bike since the resultant decrease in pitch/squat stability isn't a huge issue at the rear. On the front however, it's more important to limit pitching (since forward pitching happens regularly in DH particularly under brakes, and increases likelihood of an OTB crash). A linear spring rate curve is ideal for this, particularly in the first 3/4 or so of the stroke - something air forks fail miserably at.
tldr; bring back coil springs.
@Udi I'll give you that, I over simplified the role of a damper. But, my main point was that the spring is still the dominant piece of the puzzle, and that is still correct. It's the reason you always beat the same drum of "bring back coil springs". The spring is the biggest single piece of the puzzle, and you get that one in the ballpark first (hence adjusting spring rate by measuring sag when setting up the suspension). THEN, work on the damper. If you work on the damper first, you're doing it wrong.
Bringing it back to my original point again, that's presumably why Cane Creek put the air volume adjust in this new fork vs a hydraulic bottom out circuit.
Bringing it back to my original point again, that's presumably why Cane Creek put the air volume adjust in this new fork vs a hydraulic bottom out circuit.
@mtg for sure, no disrespect intended.
Certainly it's best to get the spring as close as possible first.
I do think it's important to have a ballpark (low-to-medium) level of damping in-play while deciding on spring rate though (particularly on the fork where sag is quite inaccurate / inconsistent to measure) to avoid the scenario Cerberus75 mentioned where the spring rate is higher than it needs to be to generate stability that would ideally be managed by the damper. I'm sure you're aware of this, mentioning moreso for fresh setups.
I do like to beat the coil sprung drum whenever the opportunity arises, just to muster up a bit of e-support for a worthy cause.
Certainly it's best to get the spring as close as possible first.
I do think it's important to have a ballpark (low-to-medium) level of damping in-play while deciding on spring rate though (particularly on the fork where sag is quite inaccurate / inconsistent to measure) to avoid the scenario Cerberus75 mentioned where the spring rate is higher than it needs to be to generate stability that would ideally be managed by the damper. I'm sure you're aware of this, mentioning moreso for fresh setups.
I do like to beat the coil sprung drum whenever the opportunity arises, just to muster up a bit of e-support for a worthy cause.
Do we start an army or a club? If club I can offer my 'shed for meetings.
TFTuned is releasing their RS/Fox coil conversion kits at Sea Otter.
These are also supposed to be on the market soon - http://www.vitalmtb.com/photos/features/EUROBIKE-2017-Mountain-Bike-Components,10434/SAR-PSP-Spring-Tuning-Kit-for-BoXXer-Lyrik-Pike-and-FOX-36,109309/sspomer,2
This guy has been selling kits for awhile now - http://www.crconception.com/
These are also supposed to be on the market soon - http://www.vitalmtb.com/photos/features/EUROBIKE-2017-Mountain-Bike-Components,10434/SAR-PSP-Spring-Tuning-Kit-for-BoXXer-Lyrik-Pike-and-FOX-36,109309/sspomer,2
This guy has been selling kits for awhile now - http://www.crconception.com/
His website is a mess but he does reply promptly to emails even in English.
He has also a All-in-one kit including a open bath damper with a coil spring. The weight is really close to the original parts, at least for the Pike he shows on his Facebook page.
The guy is highly regarded in the French forums I follow.
Half of the documentation on his site are in .jpg files which don't work in translators (and I've forgotten all of my 5 years of french lessons from school) - do you have to use his damper in the Fox version? Does he offer kits for shorter travel lengths (ie, 150mm or 140mm)?
The all in one kit does fit many different forks but I am not sure if he is doing coil spring kit for Fox... He is producing his own springs so that he can get you the length you need.
The best would be to send him an email or chat with him on his Facebook page.
Shot him a message - quick response: for his Fox solution the spring is integrated with his damper cartidge. For RS he offers a spring kit w/o damper.
I thought you liked your 36? But I can understand that some coil plushness is appealing too!
I do, but I'm also a gear whoreI thought you liked your 36? But I can understand that some coil plushness is appealing too!
. If the barrier to try something isn't too high I'll test it out. In this case though I don't think I want his homemade damper.
The price with the damper start to be non negligible if it is what is pulling you off.I do, but I'm also a gear whore
He had this damper for years so it is a well proven and reliable piece of kit.