Questions about light for long distance event
#51
Senior Member
Join Date: Jul 2009
Location: Central Coast, California
Posts: 3,370
Bikes: Colnago C-50, Calfee Dragonfly Tandem, Specialized Allez Pro, Peugeot Competition Light
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
Actually I think I did. I don't see a problem with the actual calculations. What I was disagreeing with (and this is a minor point really) is that he's saying that you're running the light 24hrs a day and most of us don't do that (unless you forget to turn them off). Most of us are only running the light between dusk and dawn. That would be a more realistic calculation. If he is running them 24hrs then it's more valid for what he's doing. That's all.
#52
Senior Member
Join Date: Jul 2009
Location: Central Coast, California
Posts: 3,370
Bikes: Colnago C-50, Calfee Dragonfly Tandem, Specialized Allez Pro, Peugeot Competition Light
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
To do a 600K in under 23 hours, your power/speed relationship was well outside the linear range. You probably ride the flats at 35kph+ where aerodynamics trump frictional losses rather quickly. The dynohub impact was probably more like 20 minutes on your time. For a slower rider using all of the allowed time, the impact would be over one hour.
#53
Zircon Encrusted Tweezers
Join Date: Nov 2008
Location: high ground
Posts: 1,348
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 261 Post(s)
Liked 132 Times
in
84 Posts
Actually I think I did. I don't see a problem with the actual calculations. What I was disagreeing with (and this is a minor point really) is that he's saying that you're running the light 24hrs a day and most of us don't do that (unless you forget to turn them off). Most of us are only running the light between dusk and dawn. That would be a more realistic calculation. If he is running them 24hrs then it's more valid for what he's doing. That's all.
*because I like to emulate the kool kids.
BTW, "Good at coasting" might make a good tag line...
#54
Zircon Encrusted Tweezers
Join Date: Nov 2008
Location: high ground
Posts: 1,348
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 261 Post(s)
Liked 132 Times
in
84 Posts
well, the assumption that a rider will ride at exactly the same power level regardless of light choice probably isn't true. But that assumption is a really good starting point. And if the watts that are wasted cause one not to ride with a faster group of riders, then the time penalty could be huge. This is why Steamer contacted you to for your opinion about testing, it's certainly an interesting question to me.
This is still not reality, but gotta be more accurate than doing it all as 200K of steady state.
Edited to add: I just realized that I don't totally understand the point you were making in your first sentence.
I thought you were commenting on the error introduced by doing the simple calc holding slope and power constant (cause that is obviously not real...). But I realize now you were saying something I bit different (I think).
Last edited by Steamer; 03-05-14 at 08:38 PM.
#55
Zircon Encrusted Tweezers
Join Date: Nov 2008
Location: high ground
Posts: 1,348
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 261 Post(s)
Liked 132 Times
in
84 Posts
Interesting. I always figured it was the other way around... (that you regretted accepting the invite...). The only ride I ever regretted was hours 21 through 23.9 of last years Fleche.
#56
Senior Member
Join Date: Jul 2009
Location: Central Coast, California
Posts: 3,370
Bikes: Colnago C-50, Calfee Dragonfly Tandem, Specialized Allez Pro, Peugeot Competition Light
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
Agreed that most probably don't. But I noticed Unterhausen rides with his light on all the time. And I started doing that too last year*. I figure it represents a small bit of life insurance.
*because I like to emulate the kool kids.
BTW, "Good at coasting" might make a good tag line...
*because I like to emulate the kool kids.
BTW, "Good at coasting" might make a good tag line...
I don't call it good at coasting, I call it having well developed descending muscles.
#57
Senior Member
Join Date: Oct 2008
Location: Portland, OR
Posts: 3,843
Bikes: Trek Domane SL6 Gen 3, Soma Fog Cutter, Focus Mares AL, Detroit Bikes Sparrow FG, Volae Team, Nimbus MUni
Mentioned: 11 Post(s)
Tagged: 0 Thread(s)
Quoted: 896 Post(s)
Liked 2,065 Times
in
1,081 Posts
The battery/dyno part of this thread captures the debate I had with myself when selecting lighting for my new rando bike. Some of my more heated discussions occurred on brevets this past fall, when finishing up my R-12. Eventually the dyno side won; I purchased a Shutter Precision dynohub and mated it with my old CYO.
The battery side is still not speaking, which makes for quieter if less entertaining rides.
The battery side is still not speaking, which makes for quieter if less entertaining rides.
#58
Randomhead
Join Date: Aug 2008
Location: Happy Valley, Pennsylvania
Posts: 24,402
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 4 Post(s)
Liked 3,700 Times
in
2,520 Posts
#59
Senior Member
Join Date: Jul 2009
Location: Central Coast, California
Posts: 3,370
Bikes: Colnago C-50, Calfee Dragonfly Tandem, Specialized Allez Pro, Peugeot Competition Light
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
Thread
Thread Starter
Forum
Replies
Last Post
BadBurrito
Long Distance Competition/Ultracycling, Randonneuring and Endurance Cycling
26
07-30-16 08:21 PM
jralbert
Commuting
92
08-16-13 10:02 AM
Mr_Wrench
General Cycling Discussion
31
11-30-10 03:31 PM