bogydave

A good number to watch to monitor progress?
Has trended up since I started riding , starting 4th year.
Last year it was 12.5

For my 890 miles this year my average
speed is 12.8
When I left SoCal, I was gaining average speed,
One 22 mile ride , no wind day, ride avg was 14.6

Now back in Alaska, my average not over 12 mph for 3 rides of 82 miles.
Some is having to walk around ice/snow,
1st exploring ride when I got back here, avg for 43 mile was 10.7 mph.

Gotta be air temp, muscles/lungs still trying to
recover from 75 -85° to 35- 40°.

donheff

I started back riding when I was 58 and I am now about to hit 70. My average speed has crept down a mile or two over the years. Doesn't bother me at all since I am out for fun on rides with my wife. I just hope I can get another 10-15+ years in - another drop of a mile or two won't bother me at all.

wphamilton

You're right, it's most likely the air temperature. The thicker air and harder tires are bad enough but for some of us, maybe you also, we just labor more and can't breath as well when it gets down to 40°

Hoopdriver

I notice occasional decrements in my average speed; however since most of my cycling is commuting on urban streets I see a lot of variability in commute times due to traffic and signal lights in particular. My cyclometer does "pause" when I am stopped for a light; however it still tallies the time and speed when I am slowing down for a stop and then getting moving again. The average speed difference between a "good green light" commute and a "every red light" commute can be 2-3 mph.

Open road riding is easier to monitor and my average speed is more consistent, though there is a definite drop in my winter times. Not sure it was the air temperature though - more likely all of the other irritations: too much clothing, cold and numb feet, mental effort to convince myself that the ride was enjoyable, and probably most important, few other riders on the road to use as rabbits (or to stay ahead of).

Notice that I avoided admitting that there may be another reason?

Jim from Boston

Average speed dropping

Quote:

Originally Posted by bogydave

A good number to watch to monitor progress?
Has trended up since I started riding , starting 4th year.
Last year it was 12.5

For my 890 miles this year my average
speed is 12.8
When I left SoCal, I was gaining average speed,
One 22 mile ride , no wind day, ride avg was 14.6

Now back in Alaska, my average not over 12 mph for 3 rides of 82 miles.
Some is having to walk around ice/snow,
1st exploring ride when I got back here, avg for 43 mile was 10.7 mph.

Gotta be air temp, muscles/lungs still trying to
recover from 75 -85° to 35- 40°.

Quote:

Originally Posted by wphamilton

You're right, it's most likely the air temperature. The thicker air and harder tires are bad enough but for some of us, maybe you also, we just labor more and can't breathas well when it gets down to 40°

FYA, see these two wonky, but illustrative graphs by @Wilbur Bud (follow the links) of commuting time by month and temp on the thread, "Winter slower than summer by about 15%," and my peculiar, completely hypothetical explanation.
I’ve done very little riding for the past five months, and I’ll be starting from near-scratch this week. It’ll be interesting to monitor my average speed incremental (hopefully) rise as a function of fitness, rather than temperature, on well-established commuter routes. I’m otherwise not competitive about it.

rm -rf

Cold air is more dense, so it takes more watts to push it out of the way.
Density at 5C / 41F: 1.27 kg per cubic meter.
Density at 30C / 86F: 1.16
It's 10% more at the low temperature. That's a bigger difference than I expected.
No wonder it's hard to go fast, air is heavy!

Other average speed factors:
Not riding as much in the winter as in the summer.
Windier conditions make a big difference.
Any slowing for stop signs will have a noticeable effect on the average.
More elevation gain
Rougher roads.
Ha -- like the post above mentioned, fewer riders to chase down! A real effect!

So, average speeds can vary a lot, and rarely match up at two different locations.

prathmann

Yes, the increased air density is certainly a major factor. But there are additional ways that colder temperatures slow you down.
Extra clothing takes some energy to flex it as you pedal and also adds wind resistance.
Grease/oil is more viscous so there's more mechanical drag.
Tire rubber is harder when cold which increases rolling resistance.
Cold air taken into your lungs reacts more slowly so oxygen uptake into your blood is reduced.
Your body expends extra energy keeping your extremities warm.

Not at all surprising that average speeds are slower in colder weather.

bogydave

I was afraid I was losing it
(Well , never really had it since I took up riding at 60)
But have made about 2 mph increase on my average over 3 years

Thought maybe I peaked, Ha ha

Heavy cold air
Equipment
Layers of clothing
Conditions (I do slow way
down on the wet spots , so not to
sling dirty water all over everything)

Thanks for more reasons to justify
the decline
It’s not all age

McBTC

If recovery time and intensity level between rides are not consistent, I'd be skeptical of the metric.

bogydave

36 mile today
45°, light wind
Avg was 12.0,
Bibs with running pants on top, not stretch kind. tight fitting
could feel pressure on legs ,
15 min or so into the ride

For sure, one cause of slow down over 36 mi, last summer on this ride was over 13
Gonna look for bib tights or better pants for over bibs

Also I noticed I don't drink as much when it's cool,
only used one bottle
need to improve that.

Washed a pound or so of dirt off the bike when I got back.

45° warmest yet...Saw lots of liquid water on the route...++++
Over 14 hours of sun now.

canklecat

My average speed varies a lot, and goes down in winter. Nothing to do with air density or anything mysterious. I'm prone to asthma and respiratory problems, so cold dry air aggravates that stuff. And this winter was very stressful, between family illness and then I was sick with flu for all of January and part of February. So my average speed dropped a lot.

Around the beginning of March I felt better, pushed harder and set a few reasonable, flexible training goals. My speed is back up, occasionally faster over distance on some 20-30 mile routes, and much faster on certain segments of half a mile to 5 miles.

But unless I'm riding the same routes repeatedly I wouldn't really be concerned about some differences in speed. My training routes are roller coasters with lots of short, steep climbs and only a few relatively flat areas. It's a tough challenge just to average better than 14 mph. But 14 mph is a casual loaf cycle toward downtown because it's mostly a 10-12 mile gradual downhill grade, hardly noticeable until you check the terrain map, or backtrack against the wind.

Hondo Gravel

Average 12.7 gravel flats and hills turned 50 in February. On Katy etc last summer average about the same 12.7. Ride a gravel grinder with 700x40 tires. In future I quit caring as long as I get on the bike and ride

RonH

Mine has been dropping slowly over the past few years. At 73 I suppose I should expect that. As long as I'm above ground and still breathing and able to ride a few days a week I'm not complaining.

ctpres

At 79, well I will be in a couple weeks - Sure it's dropping. Is it because: air is thicker, all rides now uphill, my tires are old and stiff, bike is dirty, I quit shaving my legs, way to many patches on my tubes, I gained weight, I'm on statins, my fast friends all died or moved, all my routes are west bound so earths rotation reduces my GPS speed. Even if I fix everything - I may not be any faster. But I AM STILL MOVING!

McBTC

...probably due to global warming.

bobwysiwyg

That makes two of us.

rm -rf

updating my list.

fietsbob

Never was that fast , JRA.. at maybe 7~ 10 m/hr, but given enough time, on my bike tours , I managed to go quite a ways..

Pedaling, as it were, between Pubs & Pints..

bogydave

Got out an old pair of Aerotech bike tights.
Just warm enough for 46°
Much better fit & no leg movement restrictions

WOW
avg 13.4 on a 23 mile yesterday.


Didn't realize the tight , no stretch pants over my bibs were so restricting,
They fit well 3 yeas ago, guess the shrunk or my
legs grew a bit since I started riding.


Still ready for warmer weather but still teens° at night
snow on the ground
& rivers & lakes frozen here.

caloso

There are so many factors that affect average speed that it's not a particularly useful metric. As others have posted: clothes; air temperature; tires; road conditions; wind; etc. Not to mention traffic and stop lights/signs.

However, if you can eliminate as many variables as possible, it can be a useful metric of fitness. Maybe find a benchmark route without stop signs. An out-an-back accounts for wind and elevation change.

jskash

Thank you for posting this. It fully explains why I am so much slower in the winter than the summer.

bogydave

Yea , variables. >>>>>
Garmin 520 said 23 hour recovery time after yesterday ride,
had been getting 40+ hours on the previous 3 rides.

I have a hill at the end of my ride. about 1/2 mile.
On a 25 mile, I see how fast ( speed) I can go up the hill.
sometimes I can attack it, other times I'm in low/low nearing the top, dying.

When I started 3 years ago, I hated that sucker , called it 5 mph hill.
Now , slow is 8 mph & on good days, 10 mph.

So at the end of a ride , I see how well I ride the hill.
Not sure if that works as a metric for fitness,
still learning how to pace myself.

But I no longer hate the hill.

Dudelsack 

When you wheels rotate it generates a huge force field that interacts with the force field generated by the rotating earth, and this induces capacitive resistance that impede the progress of your bicycle, causing it to go 23% slower, all things being equal. Not many people know this.

ctpres

Wonder who will be the first to ride a bike on the moon?

pesty

Personally, I don't think average speed over the course of a year is a meaningful metric unless you ride the exact same roads with the exact same equipment under the exact same conditions for the entire year. There are just too many variables. As others have mentioned, air temp and altitude will have an effect on your performance capabilities, as well as colder air and lower elevations being more dense, which will affect your speed. Tire pressure and brand/model tires you use will affect your speed. If you spend more time climbing one year than the other, or if there's more headwind.

If you want to use speed as a metric, find a velodrome and occasionally measure your performance over a set distance on the same equipment in a controlled environment.

The one thing you're forgetting to add here is that you will ALWAYS go faster when riding in an easterly direction as the Earth spins to the east. You can gain up to a 1,600kph boost (at the equator) simply by riding east.