How to get an air spring more linear: http://www.mtb-news.de/forum/showthread.php?t=435024&page=56
Team vs WC
- Thread starter Kntr
- Start date
Kirkcaldie's mechanic once made my Shiver feel like magic at Deer Valley. He said flying it to there from where I was probably made it have a bunch of air trapped in it.
He undid the top cap and it said "Pssshhhhhh" (like your mom) and suddenly my fork worked again. Don't know why it did it. Don't care it did it.
But the longer I keep this thread going to get my fork sold...the better.
He undid the top cap and it said "Pssshhhhhh" (like your mom) and suddenly my fork worked again. Don't know why it did it. Don't care it did it.
But the longer I keep this thread going to get my fork sold...the better.
Even without changing elevation, I burp the damper side of my fork(s) every once in a while........spring forks included. As damper oil breaks down, it off-gasses a bit. It basically produces an extra air spring in your fork. Shivers were really bad about it.
I farted in Butch's shiver before he left.
You can fit your starfish over a shiver upper leg?
Kudos.
Kudos.
I played wide receiver in prison.
everyone seems to have their own opinion... i had the r2c2 and the wc and have ridden both of them a LOT. not going into a whole lot of detail, but i preferred the world cup over the r2c2 in the end. boxxers never gave me any problems, but i rebuilt mine fairly often and kept it buttery. it is lame that they don't come from SRAM with the oil/grease issues handled...makes a big difference.
Needles runs teams http://dirt.mpora.com/news/jacobs-hafjell-world-cup-qualifying-gallery.html#slide-4 But i'm pretty sure sam and troy are on air. Would be interested to see exactly who is riding what.
EDIT: Word is the blackbox boxxer is air/coil http://factoryjackson.com/2012/09/05/leogang-worlds-steve-smiths-carbon-devinci-wilson/
EDIT: Word is the blackbox boxxer is air/coil http://factoryjackson.com/2012/09/05/leogang-worlds-steve-smiths-carbon-devinci-wilson/
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What year WC? Mine were good for some time but after a few seasons the solo air started getting really annoying. It's just poor build quality since I rarely bottom out my fork.
A 36 mm air fork when set to 50 psi at 9000 feet and and a vertical drop of 7000 feet, the internal pressure would drop by 5.6 psi assuming the fork did not heat up from top to bottom, but since it does warm up a bit due to the outside temperature and internal friction the pressure will eventually rise a bit 1 or 2 psi.Careful. I was told on ridemonkey that the difference in atmospheric pressure accross 6-7k of elevation isn't something that anyone would ever be able to feel in an air fork.
Maybe I am totally missing anything, but how should a change in atmospheric pressure change the pressure inside a sealed metal cylinder without any contact to the outside??? You have an effect in a tire/tube because the rubber is elastic and needs the pressure from the outside to maintain its shape. But the inside of a fork????
Does the inside pressure in a submarine rise when you dive? I don't think so.
thats a 5.6% difference at only 9000ft.
i have noticed some air-springs have this terrible tendency to dive badly (apparently from heat?) after long rides.
you have to let it "rest" for like 1 hour... before you regain mid-stroke support.
i havent seen this happen (to the same extent) on coil forks, so i guess its not only related to damping, but also to the air spring.
our biggest "vertical drop" trail, goes from almost 120000ft to 0ft. (trail ends within 200 yards of the ocean).
i dont have exact data (an air spring looses about 10psi as soon as you engage/disengage the pump).
but i normally lowered 10-15 psi from my totem (i normally run 100-110psi) at the begining of long trails, and 2psi from the tires.
a submarine is rigid. a fork changes shape (in one direction).
the effective spring-rate is affected by the cross area of the air-spring, since this area is subject to variable external pressure. (the fork changes shape in a direction perpendicular to the cross-area).
another important factor we are missing here is thermal radiation at altitude (instead of conduction).
on a bright sunny day above 10000ft (in the andes, at least), thermal radiation can make any piece of metal, exposed to the sun, hot to the touch, even though air temperature is below 50ºF. i think this can account for 1 or 2 extra psi in the air-spring.
like i said, air-springs are too unpredictable for big vertical drops.
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The stanchion tube has an effective piston area and our atmosphere is action on it as it moves in and out.
Why do we have to 'burp' forks to make them feel plush again then? The lowers seem to be pretty air tight and collect overpressure from air trapped by the seals.
The oil seals do a good job a keeping the oil in but they can act like a check valve in a air compressor and cause a slight amount of air to suck in and build up the internal pressure, also as you ride the internal temperature will rise and the pressure will increase because of it.
What's the largest elevation change you've ever done without touching your bike? (serious question) You've never noticed a difference in tires and suspension?
5psi is noticeable. You know this.
Tires yes, suspension no! Maybe tire effect overshadowed change in suspension? But I still don't see how it should affect it in a completely sealed system.
It is not sealed, think of the stanchion slider tube as a piston, or the lower casting as a reverse cup piston, as it slides in and out. The higher the external pressure on the outside of the tube will push the slider stanchion in and vice versa. If you could increase the external air pressure to 100 psi it would overcome the internal pressure of say 50 psi and compress the fork until the pressure was equalized internally to 100 psi.
I think some of the other noobs are missing what has become the main point of this thread. This guy has a trail that goes from 12k feet to 0 feet. 12k of vert. in one trail. What. The. ****. That overshadows everything else. I need to go there.
Actually he's got a 120k trail.
Even better. That dude sees magma at the end of his ride!
Even better. That dude sees magma at the end of his ride!
I love mine. What do you want to know about it?
i ride a 2012 888 evo TI now.. rode a dorado all last season.
honestly, i love both forks.. and i would not hesitate to get a dorado again. but am equally happy with the 888.
i rate the 888 a little higher in regards to never needing much love.. it just works.. always.. the dorado, needs a little more love and maintenance.. but not a lot.
honestly, i love both forks.. and i would not hesitate to get a dorado again. but am equally happy with the 888.
i rate the 888 a little higher in regards to never needing much love.. it just works.. always.. the dorado, needs a little more love and maintenance.. but not a lot.
The answers are all on a German forum...
Sweet. I know some German...
I've rebuilt it once. They're really easy to work on. Haven't had to deal with Manitou at all so can't comment there. And no issues with the stanchions. If anything I think they're better protected than on a conventional fork.
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Buy....my....World Cup.
