aharris

I haven't changed to studded tires yet and I'm still slowing down (3-6 mph ave over an hour commute). I've read about some reasons but can't find any good ones in a search. So what say you? Whats the best excuse for my slower speed?

1) Additional clothes, wind resistance
2) Mammalian diving reflex (pulse slows in cold water, maybe a similar effect in cold air)
3) Its dark and I can't see my speedometer so I don't notice when I've slowed dramatically on hills
4) Air is denser.
5) The night sky is so inspiring it causes contemplation which shunts blood to the brain and away from legs.
6) No one else out riding so I don't have an occasional pull to catch up to a roadie?

jeffpoulin

Perhaps a combination of all of them, but for #3, it may be because you can't see the road as well either.

My winter commute times are about 15% longer than in the summer.

HardyWeinberg

I always associate it w/ more clothes; I don't feel like I've sped back up in the spring until I drop the coat and tights.

In practice the distribution of commute times may not have changed at all, seasonally, it just feels like it. Traffic light timing still has more effect on my door-to-door time than rolling speed. But I definitely still feel like I work harder and go slower in the winter.

Bander

Starting up in the cold with colder leg muscles always makes winter riding seem tougher to me.

bugly64

Sometimes I think it's colder so it just feels longer, but it Montana the wind seems stronger in the winter.

Grim

All of the above.

In my case:

Not cold enough for the Baclava and heavy coat yet but 40f is a bit painful at 25mph. I find myself slowing down to 20mph on my down hills to keep my eyes from watering in the cold and to keep the wind chill down on the face.t I usually run those hills close to 30mph in the summer.

Panniers are out now for shoes and jackets creating more wind drag.

Big bulky Cygo lite adding about 4lb.


"Mammalian" (thats one of then $2 words) cold air in the lungs I tend to resist breathing as fast deep and hard trying to warm the air a little and fog my glasses less. Knees seem to take longer to loosen up as I build my pace.

dlester

I am definitely slower, but aside from any climate factors it is also because I am riding a mountain bike in the winter and a road bike in the warmer months. Friday was my first day this season with the studded tires mounted, and that really put a hitch in my giddy up. I expect, much like last year, that when spring rolls around and I get back on the road bike my average compared to last spring will be noticeably higher.

DX-MAN

I ride MTB year-round for my commute, and I see about an extra minute per mile or so when it gets really blustery, half that for just the cold. A lot of it is the extra clothing, and the WIND CHILL! You just don't get the flow of body heat as fast, or as fully. Proper layering keeps you from seizing up, not so much maintaining what you feel in summer.

cyclefreaksix

I'm slower as well when the temps dip into the low 40s. Not sure why either, but the effect is real.

Hot Potato

I googled this before. I saw a credible treatise for #1 and #4. to the tune of about a 10% change for me.

https://www.icebike.org/Articles/SlowerWinter.htm


Conclusion:

Sixty Fiver

The extra clothes and increased wind resistance are the contributing factors here... aerodynamics plays a hug role in how fast one can ride.

bmt074

It def tends to be windier where I am. Yesterday I went from 16 mph to 11 mph as soon as I turned the corner into a stiff headwind.

trekker pete

I started a thread about this early this summer. My commute times in went from 45 minutes down to about 38. This is a bigger change that I suspected. I believe reason number 1 is aero dynamics followed by cold muscles not wanting to move as readily. I think the cold air in the lungs thing doesn't happen till it gets down below freezing. In fact, I think your lung efficiency in 40 degree air is better than 80. Another factor for me is my boat anchor SLA battery aka training aid. That 7 pounds makes itself know when I hit the hills.

martianone

IMHO- air density & bulkier clothes.
On my commute there is one particular rolling hill with a very smooth gentle downgrade about
half a km long. When it is warm out, say in the 70s, if I'm going 16 km at the top & coast down, usually I hit 35 kph by the bottom. Friday morning it was 20 out, only hit 31 kph on the coast down. Same bike & tires, only difference was colder air and more clothes.

jeffpoulin

In my case, it's largely due to more drag from many winter layers plus increased caution when riding in the dark or where it's possible to encounter ice. I tend to go all out on my summer rides, but that kind of riding often seems too dangerous to me in the dead of winter.

mckenxie

Your body has to work harder (i.e. burn more calories) to maintain optimal body temps in colder weather than in temperate/warm weather. The extra energy your burn could manifest itself in decreased performance.

chephy

Well, ice and snow on the ground are a biggie...

dognamedbanjo

All of the above comments make sense. I think that when it's dark on my ride, I realize just how much I rely on my speedometer for motivation, though. If I don't know how fast I'm going, I don't tend to push to the speed I think I should be going, you know?

-Robyn

BengeBoy 

I'm fatter than I was in August; 3 lbs of extra weight explains it all.

huhenio

What is that "speed" y'all talking about?

cooleric1234

I can eat baklava regardless of the temperature outside.

Sorry, I couldn't resist. I think there are some good reasons listed here, I notice I slow down too. I think part of it is just mental though. For some reason I just don't feel like exerting myself when it's cold. Maybe subconsciously I know it's a bad idea to sweat in cold weather, even though I wear appropriate clothing and only stop once I go inside.

rumrunn6

whatever the reasons I'm prepared to see a slower commute time if I get back on the road this fall / winter. but look at it this way - in the spring and summer when all conditions are ideal you attain your best speed - this is just the converse, meaning all conditions are less than ideal

mr_antares

I noticed that my average times in the morning decreased and my average times in the evening increased at the end of daylight savings time. Temperatures were not significantly different the week before and the week after the time change, and I'm wearing about the same amount of clothing. We don't have any snow or ice yet, so that cannot be a factor.

I think it has mostly to do with it being dark: you cannot see the road as well, and you cannot see your cyclo-computer.

In my morning commute, I'm now leaving just before sunrise (instead of almost an hour before sunrise prior to the time change), so my commute is "into the light" (Westbound, so I'm going down-sun at all times). In the evening, I'm now leaving at least an hour after sunset (instead of just before sunset), so more of the commute is spent in full dark conditions.

dedhed

As a WI commuter I always notice a drop off in my average speed this time of year. My thoughts are that the bike is less efficient coming out of a garage at 20-40º, I'm less efficient at that temp, and my clothing is less aerodynamic, not to mention more of it, cold air is also denser. I also don't know if my waning with darkness attitude and bodily wear and tear add to it. I lose 1-3 mph in late fall and spring 12 - 14 avg from my summer speeds of 13-16 on a 26 mi round trip day.

https://www.bikeforums.net/bicycle-mechanics/602005-bike-suddenly-seems-sluggish-possible-causes.html

BengeBoy 

I was out for a recreational ride yesterday and I realized I was wearing enough clothing to for a weekend 'credit card' tour in the summer.

I had on shorts, socks, a light jersey, a helmet, and gloves - enough to ride around in the summer.

But I also had on long tights, a second jersey, a heavy rain jacket, a second pair of gloves, a skullcap, a rain cover over my helmet. And instead of light cycling shoes I was wearing cyclocross boots.

No wonder we're slower in the winter.