Factors affecting speed?

In article <[email hidden]>, [email hidden] says...

Quoted message said:

I've been measuring some times on a four mile course and I've been surprised at the improvement
I've gotten by tuning up the hardware. I did expect tire pressure to have a significant
improvement, but not as much as 20 seconds or more per mile.

I'll bet your conditioning is helping more than any of these other factors.

Quoted message said:

The other component I didn't think about is the friction in the chain in the deraileur and
sprockets. This may have even a greater improvment and may have decreased my time by 10 seconds
per mile.

Oddly, having a much lighter bike adds a -little- improvement, but adding bodyweight (fat) can
have a greater effect, reportedly, every 3-5lbs of fat decreases your time as much as a minute per
mile, IIRC.

Not because of the simple loss of weight, but also the improved conditioning and greater muscle mass
due to the exercise which caused you to lose the fat.

Quoted message said:

(Does anyone have specifics on bike weight and body weight contribs to time improvment?)

Improvement..................Improvement begin. biker (>50y.o.)
--------------------..................------------------------------ Correct Tire pressure......=
(20 sec/mile) Lubricated chain ............= (08-10 sec/mile) Lighter bike (~20lbs).......= (08
sec/mile) Triathlon Bike.................= (08 sec/mile)

(Even for the well-conditioned athlete, I'd expect these times to be similar, but proportional.)

Except for the TT bike (especially the aero bars), I think these numbers are too big if you assume
constant rider conditioning. I think most of the improvement is due to a better engine than it is
reduced losses.

--
Dave Kerber Fight spam: remove the ns_ from the return address before replying!

REAL programmers write self-modifying code.

David Kerber ns_dkerber@ns_ids.net said:

In article <[email hidden]>, [email hidden] says...

Quoted message said:

I've been measuring some times on a four mile course and I've been surprised at the improvement
I've gotten by tuning up the hardware. I did expect tire pressure to have a significant
improvement, but not as much as 20 seconds or more per mile.

I'll bet your conditioning is helping more than any of these other factors.

I tend to agree, but last week I posted that after getting the LBS guy to inflate and adjust my
tires, plus lube the chain, I had a 2 min improvement in a timed portion of my route (4 mile
section), overnight. ;-)

The previous times had only varied 20 seconds over the last month, then suddenly I now am
consistently riding the same route 2 minutes faster on average.

Quoted message said:

Quoted message said:

The other component I didn't think about is the friction in the chain in the deraileur and
sprockets. This may have even a greater improvment and may have decreased my time by 10 seconds
per mile.

Oddly, having a much lighter bike adds a -little- improvement, but adding bodyweight (fat) can
have a greater effect, reportedly, every 3-5lbs of fat decreases your time as much as a minute
per mile, IIRC.

Not because of the simple loss of weight, but also the improved conditioning and greater muscle
mass due to the exercise which caused you to lose the fat.

I understand, but I think what I read is that if you gain this amt of fat and have been riding that
you still lose almost a minute per mile every 5 lbs you gain, training being the same. I'm still
looking for that reference. ;-)

Quoted message said:

Quoted message said:

(Does anyone have specifics on bike weight and body weight contribs to time improvment?)

Improvement..................Improvement begin. biker (>50y.o.)
--------------------..................------------------------------ Correct Tire pressure......=
(20 sec/mile) Lubricated chain............= (08-10 sec/mile) Lighter bike (~20lbs).......= (08
sec/mile) Triathlon Bike.................= (08 sec/mile)

(Even for the well-conditioned athlete, I'd expect these times to be similar, but proportional.)

Except for the TT bike (especially the aero bars), I think these numbers are too big if you assume
constant rider conditioning. I think most of the improvement is due to a better engine than it is
reduced losses.

OK, that makes sense. I kind thought I was tending to err on the side of too large an improvement.

Thanks!

-B

In article <[email hidden]>, [email hidden] says...

Quoted message said:

David Kerber ns_dkerber@ns_ids.net said:

In article <[email hidden]>, [email hidden] says...

Quoted message said:

I've been measuring some times on a four mile course and I've been surprised at the improvement
I've gotten by tuning up the hardware. I did expect tire pressure to have a significant
improvement, but not as much as 20 seconds or more per mile.

I'll bet your conditioning is helping more than any of these other factors.

I tend to agree, but last week I posted that after getting the LBS guy to inflate and adjust my
tires, plus lube the chain, I had a 2 min improvement in a timed portion of my route (4 mile
section), overnight. ;-)

The tires will certainly make a difference, but maybe you just got a good night's sleep!

Quoted message said:

The previous times had only varied 20 seconds over the last month, then suddenly I now am
consistently riding the same route 2 minutes faster on average.

Quoted message said:

Quoted message said:

The other component I didn't think about is the friction in the chain in the deraileur and
sprockets. This may have even a greater improvment and may have decreased my time by 10 seconds
per mile.

Oddly, having a much lighter bike adds a -little- improvement, but adding bodyweight (fat) can
have a greater effect, reportedly, every 3-5lbs of fat decreases your time as much as a minute
per mile, IIRC.

Not because of the simple loss of weight, but also the improved conditioning and greater muscle
mass due to the exercise which caused you to lose the fat.

I understand, but I think what I read is that if you gain this amt of fat and have been riding
that you still lose almost a minute per mile every 5 lbs you gain, training being the same. I'm
still looking for that reference. ;-)

I hadn't heard that, but I might believe it. If you gain 5 lbs of fat, you certainly aren't
exercising very much.

Quoted message said:

Quoted message said:

Quoted message said:

(Does anyone have specifics on bike weight and body weight contribs to time improvment?)

Improvement..................Improvement begin. biker (>50y.o.)
--------------------..................------------------------------ Correct Tire
pressure......= (20 sec/mile) Lubricated chain............= (08-10 sec/mile) Lighter bike
(~20lbs).......= (08 sec/mile) Triathlon Bike.................= (08 sec/mile)

(Even for the well-conditioned athlete, I'd expect these times to be similar, but
proportional.)

Except for the TT bike (especially the aero bars), I think these numbers are too big if you
assume constant rider conditioning. I think most of the improvement is due to a better engine
than it is reduced losses.

OK, that makes sense. I kind thought I was tending to err on the side of too large an improvement.

Of course, if your route includes a major climb, a lighter bike might make a big difference!

--
Dave Kerber Fight spam: remove the ns_ from the return address before replying!

REAL programmers write self-modifying code.

"David Kerber" <ns_dkerber@ns_ids.net> wrote in message
"]news:[email hidden]...

Quoted message said:

The tires will certainly make a difference, but maybe you just got a good night's sleep!

Quoted message said:

Dave Kerber

I tend to agree. I really hate testing where there is human involvement. I remember an MTB rag a few
years ago did a "test" to prove that riding a full suspension bike up a hill was faster than riding
a hardtail with a suspension fork and faster still than riding a rigid bike. There are so many
outside factors, it's hardly a test at all!! The results may be correct, but I have serious doubts
about the testing methodology! Sort of a
pseudo-science.

Cheers,

Scott..

Badger South said:

Oddly, having a much lighter bike adds a -little- improvement, but adding bodyweight (fat) can
have a greater effect, reportedly, every 3-5lbs of fat decreases your time as much as a minute per
mile, IIRC.

What!!!?? you mean just by dropping 5 pounds I can go from three minute miles (20 mph) to two
minute miles (30 mph?) Does the benefit continue to accrue if I lose another 5 pounds (one minute
miles at 60 mph?)

I only ask because I need to lose 15 pounds... How fast would I be going if I did zero minute
miles? :-)

--

John Foltz --- O _ Baron --- _O _ V-Rex 24 --- _\\/\-%)
_________(_)`=()___________________(_)= (_)_____

Quoted message said:

The other component I didn't think about is the friction in the chain in the deraileur and
sprockets. This may have even a greater improvment and may have decreased my time by 10 seconds
per mile.

That IS peculiar. I recall seeing a Scientific American article on the physics of bicycling quite a
few years back and they said that friction losses in cycling were very small at something less then
1% of the energy expenditure. These losses were so small that the authors did not think that
improving the friction losses on a well maintained bike would have any measurable affect on
performance.

Now, that does not mean that you did not see an improvement? Maybe it was because your bike was
now quiet and you felt confident enough to bear down some. Who knows? But you chain would have had
to have been in almost inconceivalby bad shape to have affected your time that much. Of course, I
have seen some might strange things so maybe your chain was in that bad of shape. I suppose
anything is possible.

John Foltz said:

Badger South said:

Oddly, having a much lighter bike adds a -little- improvement, but adding bodyweight (fat) can
have a greater effect, reportedly, every 3-5lbs of fat decreases your time as much as a minute
per mile, IIRC.

What!!!?? you mean just by dropping 5 pounds I can go from three minute miles (20 mph) to two
minute miles (30 mph?) Does the benefit continue to accrue if I lose another 5 pounds (one minute
miles at 60 mph?)

I only ask because I need to lose 15 pounds... How fast would I be going if I did zero minute
miles? :-)

As I said, I'm not sure I recalled it correctly, and it prob. only works one way, i.e., you gain
weight, you slow a lot, you lose weight you only speed a very little.

I'll letcha know if I find the ref. again.

-B

(Pbwalther) said:

Quoted message said:

The other component I didn't think about is the friction in the chain in the deraileur and
sprockets. This may have even a greater improvment and may have decreased my time by 10 seconds
per mile.

That IS peculiar. I recall seeing a Scientific American article on the physics of bicycling quite a
few years back and they said that friction losses in cycling were very small at something less then
1% of the energy expenditure. These losses were so small that the authors did not think that
improving the friction losses on a well maintained bike would have any measurable affect on
performance.

Now, that does not mean that you did not see an improvement? Maybe it was because your bike was
now quiet and you felt confident enough to bear down some. Who knows? But you chain would have
had to have been in almost inconceivalby bad shape to have affected your time that much. Of
course, I have seen some might strange things so maybe your chain was in that bad of shape. I
suppose anything is possible.

Well, I posted my thoughts b/c I wanted to provoke discusstion, but didn't think it would be this
controversial! ;-)

But I swear to you, my times were extremely stable prior to taking the bike in for a new back tire,
and adjustment to the front (which might have been rubbing a very little bit on the brake pads-had
it adjusted once, already). When I got home I sprayed WD-40 on the chain and sprockets and
deraileur, then took a ride. My time improved by two minutes, over a rolling hilly river trail of 4
miles from 18:32 (prev. day and average over a month) to 16:15, the very next day.

I've continued to get times in the 16 minute range for the past 8 rides, with ease. Go figure... ;-)

-B

In article <[email hidden]>, [email hidden] says...

Quoted message said:

(Pbwalther) said:

Quoted message said:

The other component I didn't think about is the friction in the chain in the deraileur and
sprockets. This may have even a greater improvment and may have decreased my time by 10 seconds
per mile.

That IS peculiar. I recall seeing a Scientific American article on the physics of bicycling quite
a few years back and they said that friction losses in cycling were very small at something less
then 1% of the energy expenditure. These losses were so small that the authors did not think that
improving the friction losses on a well maintained bike would have any measurable affect on
performance.

Now, that does not mean that you did not see an improvement? Maybe it was because your bike was
now quiet and you felt confident enough to bear down some. Who knows? But you chain would have
had to have been in almost inconceivalby bad shape to have affected your time that much. Of
course, I have seen some might strange things so maybe your chain was in that bad of shape. I
suppose anything is possible.

Well, I posted my thoughts b/c I wanted to provoke discusstion, but didn't think it would be this
controversial! ;-)

But I swear to you, my times were extremely stable prior to taking the bike in for a new back
tire, and adjustment to the front (which might have been rubbing a very little bit on the brake
pads-had it adjusted once, already). When I got home I sprayed WD-40 on the chain and sprockets
and deraileur, then took a ride. My time improved by two minutes, over a rolling hilly river trail
of 4 miles from 18:32 (prev. day and average over a month) to 16:15, the very next day.

I've continued to get times in the 16 minute range for the past 8 rides, with ease. Go
figure... ;-)

If your chain was really bad, it might have some effect, but pumping up your tires, putting on a new
one (higher pressure one?), and fixing a rubbing brake would probably have a greater effect.

--
Dave Kerber Fight spam: remove the ns_ from the return address before replying!

REAL programmers write self-modifying code.

John Foltz said:

Badger South said:

Oddly, having a much lighter bike adds a -little- improvement, but adding bodyweight (fat) can
have a greater effect, reportedly, every 3-5lbs of fat decreases your time as much as a minute
per mile, IIRC.

What!!!?? you mean just by dropping 5 pounds I can go from three minute miles (20 mph) to two
minute miles (30 mph?) Does the benefit continue to accrue if I lose another 5 pounds (one minute
miles at 60 mph?)

I only ask because I need to lose 15 pounds... How fast would I be going if I did zero minute
miles? :-)

Sounds like the guy would spend a fortune on speeding tickets with one of my bikes!!!

FWIW, all other factors being equal, adding a pound to a bike / rider should only cost about 1
second in a 40km / 25 mile no turns time trial. So I'd exect that 5 pound (2.2kg) reduction to be
"in the noise" in terms of speed improvement unless it was due to the removal of a large blob of
skin that caught a lot of air... ;-)

Mark Hickey Habanero Cycles habcycles.comhabcycles.comOpen ↗ Home of the $695 ti frame

In article <[email hidden]>, [email hidden] says...

Quoted message said:

John Foltz said:

Badger South said:

Oddly, having a much lighter bike adds a -little- improvement, but adding bodyweight (fat) can
have a greater effect, reportedly, every 3-5lbs of fat decreases your time as much as a minute
per mile, IIRC.

What!!!?? you mean just by dropping 5 pounds I can go from three minute miles (20 mph) to two
minute miles (30 mph?) Does the benefit continue to accrue if I lose another 5 pounds (one minute
miles at 60 mph?)

I only ask because I need to lose 15 pounds... How fast would I be going if I did zero minute
miles? :-)

As I said, I'm not sure I recalled it correctly, and it prob. only works one way, i.e., you gain
weight, you slow a lot, you lose weight you only speed a very little.

If you are coasting down hill, gaining weight will speed you up, and on a flat course, the effect is
essentially nil.

--
Dave Kerber Fight spam: remove the ns_ from the return address before replying!

REAL programmers write self-modifying code.

David Kerber ns_dkerber@ns_ids.net said:

In article <[email hidden]>, [email hidden] says...

Quoted message said:

(Pbwalther) said:

>The other component I didn't think about is the friction in the chain in the deraileur and
>sprockets. This may have even a greater improvment and may have decreased my time by 10 seconds
>per mile.

<snipped>

Quoted message said:

If your chain was really bad, it might have some effect, but pumping up your tires, putting on a
new one (higher pressure one?), and fixing a rubbing brake would probably have a greater effect.

Right, which is why I gave that 20sec/mi and the chain thing 8sec/mi.

The most noticeable thing for me was the incredibly improved ease of pedalling, which felt (in
contrast) like it was almost all chain lubing.

Parenthetically, I had never lubed the chain figuring that Walmart would have already put grease on
it - (the chain -had- been making noises just prior to the lube job). Heck, maybe they didn't and I
was pedaling from Aug to Nov on an ungreased chain! ;-)

The new tire comment might have been misleading. Just changed the inner tube. And I know the rubbing
was only slight, b/c I had it looked at last month at the same LBS.

-B

David Kerber <ns_dkerber@ns_ids.net> wrote:
: If you are coasting down hill, gaining weight will speed you up, and on a flat course, the effect
: is essentially nil.

i would *guess* it would be more than nill. it's not like throwing on a 10 pound weight. your body
now has to support it, pump blood through it, whatever. more than nill.
--
david reuteler [email hidden]

David Reuteler said:

David Kerber <ns_dkerber@ns_ids.net> wrote:
: If you are coasting down hill, gaining weight will speed you up, and on a flat course, the effect
: is essentially nil.

i would *guess* it would be more than nill. it's not like throwing on a 10 pound weight. your body
now has to support it, pump blood through it, whatever. more than nill.

Uh, every lb of fat requires a mile of tiny capillaries! ;-}

-B

David Reuteler said:

David Kerber <ns_dkerber@ns_ids.net> wrote:
: If you are coasting down hill, gaining weight will speed you up, and on a flat course, the effect
: is essentially nil.

i would *guess* it would be more than nill. it's not like throwing on a 10 pound weight. your body
now has to support it, pump blood through it, whatever. more than nill.

True, but your aerodynamic drag stays the same, while your inertia goes up for having more weight.
Actually, depending on just where you've put the pounds, your beer belly might be aerodynamically
better than a flat torso...hence the aerobelly. I have aero equipment that you just can't buy...
--
Rick Onanian

Badger South <[email hidden]> wrote:
: On 03 Dec 2003 16:40:26 GMT, David Reuteler <[email hidden]> wrote:
:>i would *guess* it would be more than nill. it's not like throwing on a 10 pound weight. your body
:>now has to support it, pump blood through it, whatever. more than nill.
:
: Uh, every lb of fat requires a mile of tiny capillaries! ;-}

uh .. then .. why .. are .. you .. disagreeing .. with .. me?

Badger South <[email hidden]> wrote:
: As I said, I'm not sure I recalled it correctly, and it prob. only works one way, i.e., you gain
: weight, you slow a lot, you lose weight you only speed a very little.

i'm more than a "very little" bit faster than i was when i weighed more (i have weighed as much as
225, i am 175). roughly the same fitness level since
195 (iwas doing fast centuries then, too) and i am quite a bit faster at 175 even on the flats. but
holy buckets in the hills. wow.

anecdotal evidence. har. but i strongly disagree with the statement that losing weight won't help
you much on the flats. besides your statement makes no sense. if i start at 175 and go to 185 i slow
a lot, but if i lose the weight back down to 175 do i not gain the speed what i lost? why is there
significiant hysteresis in this problem? do you ever get it back?
--
david reuteler [email hidden]

Rick Onanian <[email hidden]> wrote:
: True, but your aerodynamic drag stays the same, while your inertia goes up for having more weight.
: Actually, depending on just where you've put the pounds, your beer belly might be aerodynamically
: better than a flat torso...hence the aerobelly. I have aero equipment that you just can't buy...

i'm *guessing* the physiological effects far outweigh (haha) any aerodynamic concerns. your
cardiovascular will hold out longer w/o the extra weight.
--
david reuteler [email hidden]

David Reuteler said:

Badger South <[email hidden]> wrote:
: On 03 Dec 2003 16:40:26 GMT, David Reuteler <[email hidden]> wrote:
:>i would *guess* it would be more than nill. it's not like throwing on a 10 pound weight. your
:>body now has to support it, pump blood through it, whatever. more than nill.
:
: Uh, every lb of fat requires a mile of tiny capillaries! ;-}

uh .. then .. why .. are .. you .. disagreeing .. with .. me?

Badger South <[email hidden]> wrote:
: As I said, I'm not sure I recalled it correctly, and it prob. only works one way, i.e., you gain
: weight, you slow a lot, you lose weight you only speed a very little.

i'm more than a "very little" bit faster than i was when i weighed more (i have weighed as much as
225, i am 175). roughly the same fitness level since
195 (iwas doing fast centuries then, too) and i am quite a bit faster at 175 even on the flats.
but holy buckets in the hills. wow.

anecdotal evidence. har. but i strongly disagree with the statement that losing weight won't help
you much on the flats. besides your statement makes no sense. if i start at 175 and go to 185 i
slow a lot, but if i lose the weight back down to 175 do i not gain the speed what i lost? why is
there significiant hysteresis in this problem? do you ever get it back?

Hi Dave, You may have mis-attributed those comments to me. I just posted a follow to the comment
about 'very little' speed in the flats. I actually think you can get a very significant improvement
in speed with weight loss (muscle gain with fat loss), especially if you are getting the loss due to
the exercise on the bike.

-B

Badger South said:

David Kerber ns_dkerber@ns_ids.net said:

If your chain was really bad, it might have some effect, but pumping up your tires, putting on a
new one (higher pressure one?), and fixing a rubbing brake would probably have a greater effect.

Right, which is why I gave that 20sec/mi and the chain thing 8sec/mi.

The most noticeable thing for me was the incredibly improved ease of pedalling, which felt (in
contrast) like it was almost all chain lubing.

Parenthetically, I had never lubed the chain figuring that Walmart would have already put grease
on it - (the chain -had- been making noises just prior to the lube job). Heck, maybe they didn't
and I was pedaling from Aug to Nov on an ungreased chain! ;-)

The new tire comment might have been misleading. Just changed the inner tube. And I know the
rubbing was only slight, b/c I had it looked at last month at the same LBS.

I think the brake rubbing would account for the biggest percentage of the differences you perceived.
Way, way back when my family first started biking, we encountered that problem a few times. At
first, I thought a tiny bit of rubbing was no big deal; but I eventually noticed that my young son
would take off like a rocket after I fixed some barely audible rubbing on his bike. And it wasn't
just psychological, because it worked even if he didn't know I'd fixed it.

About the psychological: that's the problem in measuring almost all cycling "improvements." If
someone becomes convinced a titanium saddlebag support will make them faster, by golly it will! It
subconsciously inspires them to push just a tiny bit harder.

Correct tire pressure does help, BTW. The change in rolling resistance with pressure is measurable.
See terrymorse.comrolres.htmlOpen ↗

--
Frank Krygowski [To reply, omit what's between "at" and "cc"]