Coil shocks?

Stevo_666

Can anyone explain why coil shocks are pretty common/the norm for DH and heavy duty usage, but aren't used much for trail/xc/lighter usage etc?

This isn't a 'coil shocks are better/worse than air shocks' thing, just realised I didn't know the reason why and now it's bugging me !

ilovedirt

Coil shocks have better small bump compliance and don't tend to heat up like air shocks do on long descents. They're also heavier.

IBISMojoHDamon

+ if the shock blows up on an air shock... you are pretty stuffed... If a coil shock let go, you still have a spring.. ;0)

jehosophat

Coil shocks used to be the norm for XC as well. When I bought my classic Heckler (basically what became the Superlight but with slightly thicker tubing, so 100mm travel) in the late 90's it had a Fox Vanilla R coil shock and that was about all you found at the time. Around the millenium air shocks started to become the norm on XC bikes but they failed, a lot, and I tried some of that period on the Heckler and they felt rubbish compared to the air shocks - poor small bump compliance and shot right through the travel for bigger stuff (a bit like early air forks). Plus I always felt there was more bob with the air shocks (this was pre pro-pedal). I had a Float RL of about 2001 vintage and it lost pressure after a season's use, plus the damping controls appeared to do nothing.

By the time I got my 06 Superlight air shocks were much better and when I tried the Vanilla in that bike alongside the strandard Float R (with pro-pedal) the differences were very slight in normal use. But the Float R did lose air pressure on the 6th ride and need a warranty repair!!! Since that repair it, and the other air shocks I have used, have been fine reliability wise...

Stevo_666

Thanks lads, I get it now

Anonymous

Air shocks are also more configurable and adaptive for a wide variety of terrain, whereas coil are better for specific purposes, such as DH.

Or there's the bottom end of the market where coil (rear) shocks are found on the cheaper than cheap bikes, have no damping, no adjustments, and are largely useless for off road. Upgrading from there to a good coil shock is probably expensive and limiting for an XC bike, so air is preferred.

ilovedirt

deadkenny wrote:

Air shocks are also more configurable and adaptive for a wide variety of terrain, whereas coil are better for specific purposes, such as DH.

That's completely untrue, most of the higher end shocks have some form of platform damping (pro pedal, etc) as well as compression (sometimes high and low speed) and rebound damping. It's just that air shocks are lighter, that's why you see them on most bikes these days apart from the big-hitters.

lostboysaint

deadkenny wrote:

Air shocks are also more configurable and adaptive for a wide variety of riders, whereas coil are designed for specific weights.

Sorted that for you.

ilovedirt

Again, not really true. They're more easily adaptable for different weights and riding styles, however it only takes ten minutes (depending how silly your linkage is) to change a spring on a coil shock.

lostboysaint

ilovedirt wrote:

Again, not really true. They're more easily adaptable for different weights and riding styles, however it only takes ten minutes (depending how silly your linkage is) to change a spring on a coil shock.

If you have the right length and rating of spring and the tools.

And you don't put on any weight/lose any so that the spring that remains is within the compression settings of the shock (usually a wound platform to lengthen or shorten the spring)

And everyone that walks through the bike shop door is the same weight as the stock spring design......

Or you just bung an air can on it and flog a shock pump.

I wonder which one motivates the bike industry more...................

sandy771

lostboysaint wrote:

And everyone that walks through the bike shop door is the same weight as the stock spring design......

This was my problem with the Trance X4 - the bike wasnt right for me at 17st in my biking kit. An upgrade to the X3 put me on a bike that had a sufficient range of adjustment to keep me happy.

ilovedirt

lostboysaint wrote:

ilovedirt wrote:

Again, not really true. They're more easily adaptable for different weights and riding styles, however it only takes ten minutes (depending how silly your linkage is) to change a spring on a coil shock.

If you have the right length and rating of spring and the tools.

And you don't put on any weight/lose any so that the spring that remains is within the compression settings of the shock (usually a wound platform to lengthen or shorten the spring)

And everyone that walks through the bike shop door is the same weight as the stock spring design......

Or you just bung an air can on it and flog a shock pump.

I wonder which one motivates the bike industry more...................

Like I said, they're more easily and cheaply adaptable. They're still just as adaptable. Besides, who notices a few PSI of difference in an air shock? I sure as hell don't....

lostboysaint

ilovedirt wrote:

lostboysaint wrote:

ilovedirt wrote:

Again, not really true. They're more easily adaptable for different weights and riding styles, however it only takes ten minutes (depending how silly your linkage is) to change a spring on a coil shock.

If you have the right length and rating of spring and the tools.

And you don't put on any weight/lose any so that the spring that remains is within the compression settings of the shock (usually a wound platform to lengthen or shorten the spring)

And everyone that walks through the bike shop door is the same weight as the stock spring design......

Or you just bung an air can on it and flog a shock pump.

I wonder which one motivates the bike industry more...................

Like I said, they're more easily and cheaply adaptable. They're still just as adaptable. Besides, who notices a few PSI of difference in an air shock? I sure as hell don't....

We're in broad agreement, but you're idea that a coil shock is easily adjustable is quite amusing. IF you can find a replacement spring of the right rating etc.

Can't you? I can! But then I'm probably bigger and heavier than you and a lifetime of sitting on coil sprung motorcycles and both coil and air sprung mountain bikes may have given me an edge.

ilovedirt

Aside from spring rate not being as tunable, they are just as adjustable, a lot of them more so.

I might be able to tell a slight difference in a few PSI, but it's not something that really concerns me unless I'm blowing through travel silly fast... I'm pretty happy with an approximate spring rate on a coil shock, as long as it's somewhere near right.

Also, the wound platform you mention has nothing to do with compression damping, that's preload, totally different kettle of fish. And what tools do you need to change a spring, aside from a couple of allen keys and a new spring?