r80andr100rt
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Fork springs, tight coils up or down? Thanks.
- Thread starter r80andr100rt
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r80andr100rt
New member
If the closer coils are softer I think that they should go in first. The reason is the rest of the spring would remain relatively sill in the tube as the close coils compress and expand.
If the close coils are softer and placed at the top of the tube the entire spring would have to move back and forth before the softer close coils compress.
Maybe I should put on my tinfoil hat.
If the close coils are softer and placed at the top of the tube the entire spring would have to move back and forth before the softer close coils compress.
Maybe I should put on my tinfoil hat.
Jeff488
Aspiring Profligate
Can you explain why, please?
pffog
Small road corner junkie
The unsprung weight comment partly explains it. But basically the tighter coils are denser, thus have more mass to move, plus more inertia on rebound. The KISS answer, would you rather quickly pick up a bowling ball or a tennis ball, and which one could you do so without moving the rest of your body and not just your arm.
Jeff488
Aspiring Profligate
I always thought that the closer ones are softer, too.
It doesn't seem to me that unsprung weight is a critical factor in a vehicle as agricultural as an airhead,
and also seems to me that one would want the soft part of the spring to be affected first by the compression. I'm no engineer. Just curious.
I don't know about how lift kits affect suspension geometry, and how the supposed use of the lifted vehicle makes a difference, but it seems that there would be factors between the two types of vehicle that make a comparison an iffy proposition.
pffog
Small road corner junkie
The soft part of the spring IS effected first, regardless of its position in the spring. Remember the basics, every action has an equal and opposite reaction. a spring is just a long torsion rod, that is coiled, so the compression really imparts a twisting force in the cross section. If the soft end is at the top, it ill still be compressed first, regardless of which end is moved, because the reaction is the mass and gravity pushing on the top.
bikerfish1100
New member
I put the tighter wound coils on top because that is what the manufacturer (Wilbers) recommended for my F800GS. Can't see an appreciable difference between airhead and F suspensions in that regard.
I figure Wilbers knows suspension much better than I, so their recommendation is sufficient.
it's sort of like asking "how does counter-steering work?" Who the hell cares? Just knowing that it does is sufficient, and my knowing/not knowing changes nothing in the application of the technique.
I figure Wilbers knows suspension much better than I, so their recommendation is sufficient.
it's sort of like asking "how does counter-steering work?" Who the hell cares? Just knowing that it does is sufficient, and my knowing/not knowing changes nothing in the application of the technique.
Jeff488
Aspiring Profligate
I wasn't trying to be contentious, but just want to know why.
Curiosity often leads me to ask why a thing should be done one way rather than another. That understanding, aside from satisfying the desire to know, can help do something in a better way.
I was curious about counter-steering too, and having learned how it works, also learned to be a slightly better rider.
Curiosity often leads me to ask why a thing should be done one way rather than another. That understanding, aside from satisfying the desire to know, can help do something in a better way.
I was curious about counter-steering too, and having learned how it works, also learned to be a slightly better rider.
toooldtocare
Active member
The last time I replaced a set of fork springs with progressive springs (95 R100RT in 1998) I remember putting the tighter coils up. I think it was because I would not have to recalculate how much fork oil to put back in since the coils did not displace anymore than the stock ones. That was my reasoning anyway, at the time.
Wayne
Wayne
bikerfish1100
New member
I fully agree with the curiosity aspect, and that sometimes understanding how leads to a better overall comprehension of the subject.
however, I would love to hear how your understanding the physics of exactly how counter-steering works translates into superior performance with its usage. much like other laws of physics, "how" is an esoteric realm, and matters naught in the functionality. to wit: we have only a rudimentary understanding of all the dynamics of gravity, especially as it relates to interplanetary objects, yet no one seems to have trouble operating under the premise that things fall down, not up.
It is much the same with countersteering- the exactitude of "how" it works is relatively inconsequential when compared to the realization of how to make it happen. and THAT does not require any understanding of the dynamics of how.
care to describe how it might have been different than that for you?
(apologies for the mini-hijack, but the "coils up or down?" question seems to have been answered)
Jeff488
Aspiring Profligate
As it was explained to me, when the handlebars are turned to the left, for instance, that action "drives" the contact patch to the left and thus moves it out from under the CG of the bike. This results in the bike leaning and turning to the right.
When enough lean is acquired to make the desired turn, the movement of the bars is adjusted to keep the turn constant for however long is needed.
When I first learned this, I realized that small objects in the road can be avoided by a small quick handlebar movement. Seems to be most helpful when one is caught by surprise in encountering said objects. Sort of an object lesson in paying closer attention(beg pardon).
Greater minds than mine work on understanding gravity. For our purposes though, it seems that thinking of it as an ever diminishing force acting on all physical matter and emanating radially from the earth's core would be sufficient. Perhaps the interplanetary dynamics can be left to those who may ride on Mars.
When enough lean is acquired to make the desired turn, the movement of the bars is adjusted to keep the turn constant for however long is needed.
When I first learned this, I realized that small objects in the road can be avoided by a small quick handlebar movement. Seems to be most helpful when one is caught by surprise in encountering said objects. Sort of an object lesson in paying closer attention(beg pardon).
Greater minds than mine work on understanding gravity. For our purposes though, it seems that thinking of it as an ever diminishing force acting on all physical matter and emanating radially from the earth's core would be sufficient. Perhaps the interplanetary dynamics can be left to those who may ride on Mars.
bikerfish1100
New member
if you google "countersteering" you will get a multiplicity of answers as to how & why the physics of it operates.
so many in fact, that trying to sort out the "almost but not quite", or the "really, dude?" from the "dead on, that's it!" becomes such a time consuming game that a very simple "press left go left, press right go right" in combination with "don't think about it, just do it", and a "it's really just a sprinkling of magic fairy dust" gives all that most people need to work with it.
I've gotten to the point with students that I can see when the gears in their heads start to jam up, and just suggest that they tell their brains to STFU, and just try it. Works most every time.
so many in fact, that trying to sort out the "almost but not quite", or the "really, dude?" from the "dead on, that's it!" becomes such a time consuming game that a very simple "press left go left, press right go right" in combination with "don't think about it, just do it", and a "it's really just a sprinkling of magic fairy dust" gives all that most people need to work with it.
I've gotten to the point with students that I can see when the gears in their heads start to jam up, and just suggest that they tell their brains to STFU, and just try it. Works most every time.
