Suspension energy losses?

Hi All,

I went for a MTB ride today. The first real MTB ride in many months. My
bike has full suspension which I like from a comfort and control
perspective. I dropped decisively my riding buddies for the first time
ever. This caused much good natured teasing and joking at my expense,
as well as the observation that were I to get a "real" cross-country
hard-tail bike, I would be even more of a menace. I do not agree. I do
not belive that a fully suspended bike wastes an appreciable amount of
energy while riding, either seated or standing. I never lock my front
fork either, as the slight po-going while standing does not bother me.

So what is the deal? Do FS bikes waste energy? Anyone have some data to
back up any claims?

Joseph

wrote:
Hi All,

I went for a MTB ride today. The first real MTB ride in many months. My
bike has full suspension which I like from a comfort and control
perspective. I dropped decisively my riding buddies for the first time
ever. This caused much good natured teasing and joking at my expense,
as well as the observation that were I to get a "real" cross-country
hard-tail bike, I would be even more of a menace. I do not agree. I do
not belive that a fully suspended bike wastes an appreciable amount of
energy while riding, either seated or standing. I never lock my front
fork either, as the slight po-going while standing does not bother me.

So what is the deal? Do FS bikes waste energy? Anyone have some data to
back up any claims?

Joseph

I guess you can be curious but does the bike fit? Work? Get you
'there'?
Does it work for you? Why do you care about the coffee shop opinion?

Find a hardtail for a ride, ride the same route-then decide.

wrote:
Hi All,

I went for a MTB ride today. The first real MTB ride in many months. My
bike has full suspension which I like from a comfort and control
perspective. I dropped decisively my riding buddies for the first time
ever. This caused much good natured teasing and joking at my expense,
as well as the observation that were I to get a "real" cross-country
hard-tail bike, I would be even more of a menace. I do not agree. I do
not belive that a fully suspended bike wastes an appreciable amount of
energy while riding, either seated or standing. I never lock my front
fork either, as the slight po-going while standing does not bother me.

So what is the deal? Do FS bikes waste energy? Anyone have some data to
back up any claims?

No data, just suppostion. I have never ridden a FS bike but have been
wondering about their possible advantage because I have noticed the
fatigue and additional challenge in maintaining control of the bike on
a hardtail when riding over technically challenging terrain that is
continuously very bumpy or rocky.

As I understand it, the FS bike is heavier and more expensive than a
hardtail of the same quality for the rest of the bike, and it's hard
for me to believe that the FS is as efficient in transferring power to
the wheel on more moderate terrain. But I also suspect that the FS will
absorb energy that must be absorbed by your body with a hardtail and
that it is entirely possible that in many cases you will be faster on a
FS. Jostling of muscles causes them to fatigue.

I would be interested to hear other opinions on this myself, in case I
ever have a couple thousand or so dollars lying around that I could
spare for a quality lightweight FS.

wrote:
So what is the deal? Do FS bikes waste energy? Anyone have some data to
back up any claims?

I'd be curious to know where you dropped them. I've witnessed that a FS
bike is faster on rough terrain provided that you are not climbing.
Many years ago I was in a friendly dual with the owner of Intense, he
on a full suspension bike and me on my MB-1 (no suspension). It was a
flat section with alternating rough and smooth parts. On the smoother
areas I would pull ahead, but on the rough spots he would pull ahead...
the difference was not subtle. The rough parts were not super rough
either, but I was bouncing around a little. Since I was a stronger
rider, I think the suspension was definately helping overall.

On climbs you'd be better off with less weight and less pogoing.

Qui si parla Campagnolo wrote:
wrote:
Hi All,

I went for a MTB ride today. The first real MTB ride in many months. My
bike has full suspension which I like from a comfort and control
perspective. I dropped decisively my riding buddies for the first time
ever. This caused much good natured teasing and joking at my expense,
as well as the observation that were I to get a "real" cross-country
hard-tail bike, I would be even more of a menace. I do not agree. I do
not belive that a fully suspended bike wastes an appreciable amount of
energy while riding, either seated or standing. I never lock my front
fork either, as the slight po-going while standing does not bother me.

So what is the deal? Do FS bikes waste energy? Anyone have some data to
back up any claims?

Joseph

I guess you can be curious but does the bike fit? Work? Get you
'there'?
Does it work for you? Why do you care about the coffee shop opinion?

Find a hardtail for a ride, ride the same route-then decide.

I don't care even if it does waste some energy. I like FS, and I
believe the advantages are well forth the extra weight and complexity.
I just wonder why so many bogus things are taken as self-evident truths
by so many, particularly when the bogus info comes from people faster
than others. If they are faster than me, they must be right, right?
Seems to be the way it goes.

Joseph

Ron Ruff wrote:
wrote:
So what is the deal? Do FS bikes waste energy? Anyone have some data to
back up any claims?

I'd be curious to know where you dropped them. I've witnessed that a FS
bike is faster on rough terrain provided that you are not climbing.
Many years ago I was in a friendly dual with the owner of Intense, he
on a full suspension bike and me on my MB-1 (no suspension). It was a
flat section with alternating rough and smooth parts. On the smoother
areas I would pull ahead, but on the rough spots he would pull ahead...
the difference was not subtle. The rough parts were not super rough
either, but I was bouncing around a little. Since I was a stronger
rider, I think the suspension was definately helping overall.

On climbs you'd be better off with less weight and less pogoing.

We stuck to very non-technical dirt roads and a little singletrack.
Very little climbing and virtually no technical sections. I could drop
them at will at any section. Certainly less weight helps for climbing,
but I suspect that the FS advantage or disadvantge is primarlity
related to rider preference. I think the wasted energy (if there is
any) is so small it ends up making no difference, or at least less
difference than the negative effects of a rider using something they
felt was uncomfortable.

Joseph

Joseph Santaniello writes:

I went for a MTB ride today. The first real MTB ride in many
months. My bike has full suspension which I like from a comfort and
control perspective. I dropped decisively my riding buddies for the
first time ever. This caused much good natured teasing and joking at
my expense, as well as the observation that were I to get a "real"
cross-country hard-tail bike, I would be even more of a menace. I do
not agree. I do not believe that a fully suspended bike wastes an
appreciable amount of energy while riding, either seated or
standing. I never lock my front fork either, as the slight po-going
while standing does not bother me.

Of course suspension absorbs energy, but it gives back more control
when traveling over rough stuff. For climbing, there is a lockout
option on some suspension to avoid those small losses but the main
purpose is to not have suspension interfere with the pedal strokes.
It is less efficient to pedal against a moving support that yields
with pedal force (bounce).

So what is the deal? Do FS bikes waste energy? Anyone have some
data to back up any claims?

Shock absorbers get warm and that energy has got to come from the
motor just as with a motor vehicle.

Jobst Brandt

wrote:
Joseph Santaniello writes:

I went for a MTB ride today. The first real MTB ride in many
months. My bike has full suspension which I like from a comfort and
control perspective. I dropped decisively my riding buddies for the
first time ever. This caused much good natured teasing and joking at
my expense, as well as the observation that were I to get a "real"
cross-country hard-tail bike, I would be even more of a menace. I do
not agree. I do not believe that a fully suspended bike wastes an
appreciable amount of energy while riding, either seated or
standing. I never lock my front fork either, as the slight po-going
while standing does not bother me.

Of course suspension absorbs energy, but it gives back more control
when traveling over rough stuff. For climbing, there is a lockout
option on some suspension to avoid those small losses but the main
purpose is to not have suspension interfere with the pedal strokes.
It is less efficient to pedal against a moving support that yields
with pedal force (bounce).

So what is the deal? Do FS bikes waste energy? Anyone have some
data to back up any claims?

Shock absorbers get warm and that energy has got to come from the
motor just as with a motor vehicle.

But how much energy is it? What order of magnitude is it compared with
other energy losses on a bike? Not even getting into the amount of
energy used to heat a butt by applying a seat repeatedly!

Joseph

Joseph Santaniello writes:

I went for a MTB ride today. The first real MTB ride in many
months. My bike has full suspension which I like from a comfort
and control perspective. I dropped decisively my riding buddies
for the first time ever. This caused much good natured teasing
and joking at my expense, as well as the observation that were I
to get a "real" cross-country hard-tail bike, I would be even more
of a menace. I do not agree. I do not believe that a fully
suspended bike wastes an appreciable amount of energy while
riding, either seated or standing. I never lock my front fork
either, as the slight po-going while standing does not bother me.

Of course suspension absorbs energy, but it gives back more control
when traveling over rough stuff. For climbing, there is a lockout
option on some suspension to avoid those small losses but the main
purpose is to not have suspension interfere with the pedal strokes.
It is less efficient to pedal against a moving support that yields
with pedal force (bounce).

So what is the deal? Do FS bikes waste energy? Anyone have some
data to back up any claims?

Shock absorbers get warm and that energy has got to come from the
motor just as with a motor vehicle.

But how much energy is it? What order of magnitude is it compared
with other energy losses on a bike? Not even getting into the
amount of energy used to heat a butt by applying a seat repeatedly!

As you may have noticed the shock absorber does not get HOT to the
touch so the energy is not large, while the bounce that interferes
with pedaling is a bigger problem and that depends on the ability of
the rider to negate that effect in the absence of a lockout mechanism
(that's why it's there).

Jobst Brandt

In article ,
wrote:

Joseph Santaniello writes:

I went for a MTB ride today. The first real MTB ride in many
months. My bike has full suspension which I like from a comfort
and control perspective. I dropped decisively my riding buddies
for the first time ever. This caused much good natured teasing
and joking at my expense, as well as the observation that were I
to get a "real" cross-country hard-tail bike, I would be even more
of a menace. I do not agree. I do not believe that a fully
suspended bike wastes an appreciable amount of energy while
riding, either seated or standing. I never lock my front fork
either, as the slight po-going while standing does not bother me.

Of course suspension absorbs energy, but it gives back more control
when traveling over rough stuff. For climbing, there is a lockout
option on some suspension to avoid those small losses but the main
purpose is to not have suspension interfere with the pedal strokes.
It is less efficient to pedal against a moving support that yields
with pedal force (bounce).

So what is the deal? Do FS bikes waste energy? Anyone have some
data to back up any claims?

Shock absorbers get warm and that energy has got to come from the
motor just as with a motor vehicle.

But how much energy is it? What order of magnitude is it compared
with other energy losses on a bike? Not even getting into the
amount of energy used to heat a butt by applying a seat repeatedly!

As you may have noticed the shock absorber does not get HOT to the
touch so the energy is not large, while the bounce that interferes
with pedaling is a bigger problem and that depends on the ability of
the rider to negate that effect in the absence of a lockout mechanism
(that's why it's there).

The latest technology, which the poster's bike may or may not have, is
"stable platform" valves, now typically available on both forks and
shocks. The mechanism is roughly a spring-suspended weight which tends
to respond to sudden shocks but not to the steady motion of the pedals.
since the weight determines whether (or in some cases, how much) the
suspension is locked, it functions as an automatic lockout mechanism
which, in the better implementations, is supposed to be so fast it can
even unlock itself momentarily on climbs to deal with small,
traction-robbing obstacles.

Power meter data might give you the answer you seek (if they were
hub-based), but racing lap times are probably a pretty good proxy for
energy losses, and they would be about the most direct measure of what
you really care about, the "net energy" gained or lost with the bike* on
that type of course.

I tried googling up some stuff on this:

Annoyingly, I can't tell from the abstract which bike was the hardtail:
http://biomech.me.unr.edu/wang/abstr...nsion_test.htm

This one is a bit specialized, but the "Paul N" in this topic is a guy I
know and a very experienced racer. He's talking about the 6-day, 600km
TransRockies Challenge, one of the most epic MTB races on the planet. FS
bikes excel in marathon events like this, but he also says the FS bikes
can go up "technical" climbs faster than hardtails:

http://www.transrockies.com/forum/vi...&postdays=0&po
storder=asc&highlight=&sid=f43f74204f00f7c286842b1 c8b276e34

http://www.google.com/search?hl=en&l...&rls=en&q=s u
spension+hardtail+lap+times&btnG=Search


*It is possible you might see a net loss on a particular course for the
FS bike but still prefer it for reasons of fatigue-reduction, being able
to hit bigger obstacles, or just because it's fun.

--
Ryan Cousineau http://www.wiredcola.com/
"I don't want kids who are thinking about going into mathematics
to think that they have to take drugs to succeed." -Paul Erdos