Rich and I try to determine just how much a flag on your trike might be slowing you down. Yes, highly unscientific, but at least we're keeping busy. :)
Weight does make a difference in carry through and can be much more pronounced on some types of terrain. Even slight variations in clothing and gear make huge differences. What about the wheel bearing brands and lubes and hub temps at the beginning and end f each run? My suggestion is to to perform MANY runs with the calmest winds possible and use the same single bike and same rider with and without the flag and a precise timing mechanism over a precise distance. Nevertheless I tend to think you demonstrated that there is a drag penalty.
What about body weight? Do you weigh more than your friend? That could account for greater downhill speed. You might want to try both trikes, no flags a couple of times so you're sure you're getting consistent results and then switch trikes.
@@bikestrikesrazors Trust me, LOTS of stuff doesn't occur to me. Just ask my wife. 😉 Thanks for the compliment! It's really weird because I thought I was subscribed to you but this video didn't come up in my feed and now I see the Subscribe button above, so I'll try it again. Really enjoy your videos as well!
Last run the other guy had a much smaller camera rig- did you swap? Also, try with the flag on your bike instead. And swap bikes on another run. All those rides up and down that hill could take a week just figuring out an accurate control run! But fitness (and research) can be fun after all!
I don’t know why it never occurred to us to just swap the flag to the other trike, Ross! Now we need a follow-up video doing just that. Oh yeah, having to repeatedly pedal back up that hill was no fun at all. :) And you’re right- Rich was holding the larger camera rig for most of the runs, which I’m sure made a difference.
Drag increases with the square of velocity. So 20 mph would have 4 times the drag as 10 mph. At thirty mph it would be nine times the drag as 10 mph. That is you have 30x30=900 and 10x10=100. So streamlining is more important as your speed increases. As the demonstration shows a streamlined flag can make a difference at speed. One thing you didn't talk about is driver weight. A heavier person would provide more gravitational force to over come drag. You must be pretty equal though as the run without the flags don;t show a lot of difference.
Agree on the unscientific part. That seems to be quite an opening up that more factors probably come in to explain the speed differences. One thing that I know from the bottom of my gut, is that spending time in hospital because a car driver did not see you is a real drag. Good video, thanks.
isn't there any tie rod in those trikes ? if so, the front wheel geometry might be slighly different on his compared to yours, if he has more toe in or toe out than you, it can create rolling resistance.
The Ice flag mount orientation is so nice with that rear rake. I have a Catrike Dumont and it's vertical. I didn't like getting slapped in the helmet and ear so I run without one and stick mostly to trails.
I never thought about that, Dean. That rake does keep it away from your head, but may be why it tends to fly out of the holder at high speeds. :) I guess that's better than getting hit in the head! I'm tending to stick to trail these day as well. When I hit the road it's in residential areas with hardly any traffic and I'll run a blinky just in case.
You are correct, nothing beats the safety aspect of a flag on a trike. BTW, it looks like you have a great riding environment in your area. Down here in SoCal it is not as bike- friendly , but OK. I am very near retirement and I want to get into Bike/Trike/ Recumbent Group rides when I retire, as an organizer. I would appreciate any helpful hints in the future.
Hey, Evan! Don't know where you are in Southern California, but the Trike Squadron down there is a good group and Glenn Frank does a good job of organizing the rides. He'd be the guy to talk to about what it takes to get a group going: facebook.com/groups/118026551592095
@@bikestrikesrazors Excellent, my wife and I live in Sierra Madre and we will figure it out. She rides a VTX and I am still on two wheels. I act as the forward spotter and she watches for vehicles from behind. Symbiosis on the road. I envision a group ride with all types except e-bikes. (They can do their own thing). Thanks a million.
I run one pole, two flags. US flag and Texas state flag. I read somewhere that the American flag is very attention getting with a respect. The state flag depends on which state but also it gets respect. I go around in suburb bike lanes but the roads sometimes get traffic and I notice people getting over the other lane when passing me. Plus I get residents waving when they see me. It is sort of an odd sight to see a 65 year old man on a tadpole trike with a cowboy hat on and sunglasses rolling along usually in the heat of the day.
No flags here, for this performance rider after the first three years, or so. I just found a state-of-the-art flame thrower blinkie for the back, and same level of DRL (daytime running light) for the front and a powerful asymmetrical lamp for night riding. After 50,000 miles in 13 years, (with the motorons on North Texas roads, no less), no one nearly hits me because they don’t see me. The opposite problem exists, where they are so attracted to this fast moving exotic machine, that they get closer and closer for a better look. That’s the danger, not lack of being visible, after all, who runs over an 18-wheeler retread, or a full bag of trash in the middle of the road? Let me help you out…no one.
I got in a nice 50-mile ride yesterday. Ride Ataxia in Denton. Went up to Ray Roberts lake. Oh my, that chip seal got my Catrike 700 vibrating like crazy, harder to hold any speed on that stuff. Perfect weather, made it for a great day. Just need to keep up my cadence and speed!
@@TomWalterTX Sounds like a great ride! As bad a chip seal can be on a trike, I've got a Reynolds T-Bone 2 wheel recumbent that basically stops dead when it hits chip seal!
I'd also say, swap trikes and see what happens. A slight difference in toe, or bearing preload... all sorts of things could be variables that are unaccounted for. Should try the same run minus flags with theriders doing it a second time on the other riders trike... possibly a difference in drag from the trikes, or body shape even.
I love the various tests you guys do. It shows a curiosity about the world of recumbents and the notion of testing prevailing wisdom. Two observations about this test: 1) Was not convinced a skinny fiberglass pole and a bit of flapping material caused the visible speed difference. 2) I rarely attain speeds above 18mph so flag drag is probably not a concern for me. Here is a test I would like to see if possible...Which is better? Pedals making contact at toes (front of foot) or foot positioned on pedal at instep (middle of foot)? Which position gives most power, or does it matter?
Thanks very much, Bruce! That pedal test sounds interesting. I'm wondering if we'd need a pedal-based power meter for that? Hey, thanks for a good excuse for buying a pedal-based power meter! :)
I propose that positioning the pedal spindle at the bony ball of the foot provides more power than positioning the soft tissue of the instep over the pedal spindle. This has been demonstrated by racing cyclists consistently over the past century. There is also much less likelyhood of soft tissue injury to the plantar faschia tendon that runs from the ball of the foot to the heel. The first position also makes foot/pedal alignment easier, reducing repetitive injury risk to ankles, knees and hips. Having been a skilled time trialist, long-distance cyclist, I could use the combination of bike fit, pedal alignment, muscle strength and fitness to feed power into the rear wheel for maximum efficiency, speed, and endurance.
@@phyllisboone8957 I was using Speedplay (my knees like that pivot) on Lake Racing shoes and experienced "hot foot". I'm now using SIDI Mountainbike shoes (much easier to walk on) with Shimano PD-M8120. No hotfoot with those shoes and pedals.
@@TomWalterTX I've switched over to a great Bontrager mountain bike shoe with Spd cleats. I too find walking to be much easier, and have more stability, especially when I need to help my disabled husband with mounting or dismounting his trike. Guess that's just common sense! I did need to spend some time adjusting the cleat and pedal interface to keep my knees happy, though!🙂🙂🙂
I have a "Purple fade" flag on my recumbent and I'd say that I get similar results. Yes there is some drag but miss a green light and there is no overall difference between a ride with the flag and without. I commuted 23 miles each way and had plenty of runs to compare and honestly you can't tell by time which days I rode with a flag and which days I did not. That said I can tell that drivers see me sooner with the flag up because I can see them adjust to go around me sooner, ie farther away from me they slide either to the next lane or towards the center of the road to give me more room. My current working theory is that they think I'm a disabled rider and need more room :) Also from sailing I know that the streamer is fluttering because it's creating more drag at the tip of the pole. It's a benefit for night riding as the reflections from it are wild but it adds more drag. That could be in part why the ICE flag flopped around more. Anyway drag or no drag the flag is up all the time.
Hi Gary and thanks for watching! I think the safety concerns far outweigh any drag considerations unless you're racing a time trial. :) There was one time when flags were MORE dangerous. I was riding with a group of trikers and we all had large colorful flags. We turned from a bike trail onto a bike lane on a busy street. The driver coming down the road was either so surprised or he just wanted to slow down and look at us that the car behind him had to slam on his brakes to avoid an accident. Lots of squealing brakes.
Nice video . I do agree….fly that flag anytime you are riding in traffic. The differential was certainly within margin of error and their are other parameters…..were you guys on the same rings front and back? Is there a big weight difference between the two of you? Weight from accessories on trike? Fun demo. Thanks for sharing. I’m using my flag whenever there is traffic interaction. BTW…I have had my new 700 for two weeks and put 350 miles on it already while showing my 559 only 50 miles of love in that period. It is so light and fast it is scary.the 559 is a luxury sedan.the 700 is a Porsche 911. Both fabulous machines.
Hey, Mark! Yep, I saw your video in which you were discussing your 60 mile ride on your 700. Careful you don’t get addicted to that speed or you’ll never go back to the 559. :) Lot’s of variables between the two trikes in the video. We’ll have to do a follow up and just swap the flag between the trikes.
@@bikestrikesrazors ..I’m sure you can have fun changing out the variables and making new videos. Regardless…you guys were really cooking along.as far as the speed addiction with the 700…I have to share the love with my 559. When riding with my buddies who are slower riders on nice casual trips it will be the 559. Out on my own to really cook it and get a workout it’s the 700. The 700 has a harsher ride due to the thin tires and any path with some rough spots will probably be graced by the 559. My quandary…. Which one do I take to Florida for the winter? I have a large Toyota Highlander so I might fold the 559 and place it inside and put the 700 on my Hitchrider rack. Such a problem……
So it's either lose a couple car lengths with a flag, or increase the risk of getting hit by a car to save a couple car lengths... Hmmmmm................ LOL Yeah,, I'll keep my flag. In fact, I'm going to get a bigger one. That way I can use it as a sail when the wind is right also. LOL
Kudos on a fun, and mostly scientific experiment. I was surprised on the result that the drag was that measurable. Others have suggested how to make the experiment better. If you wanted to do a more perfect experiment, you would probably need 10 riders each making 10 runs on different days. And of course, you would need to record total vehicle weight with rider, ambient wind speed, ambient temperature, UV index, tire pressure, average viscosity of the wheel bearing grease, average speed of each run, etc and plot against those variables to make sure which variable did or did not have an effect. Not what you signed up for , is it? But, at the end of the day, (actually at the beginning of the day) I’m wearing my flag. I ride for aerobic exercise. Speed is fun. Slogging up hill is fun. But, If I go downhill 0.1% faster, it is not 0.1% funner. Leaving my flag at home is like saying I’m leaving my water bottle and repair kit at home because it will slow me down. So, put me down for : always take my flag, water bottle, repair kit, mobile phone , and self ID. Regardless of how much they slow me down.
Of course, you’re right Rudy. Any minor gain in speed isn’t worth making yourself less safe. It is fun though just to see the difference it makes to ride with/without the flag. For me to conduct and experiment that’s as comprehensive as the one you suggest, someone’s gonna have to start paying me. :)
Weight makes a huge difference. I weigh about 90-100 lbs more than my wife. No matter what bike I'm on (recumbent or road bike), when we coast downhill she ALWAYS starts out ahead and then I end up passing her and going much faster. The other factors chukran suggests may also be important, but I would have just suggested using only **one** trike with the same **one** rider, doing the exact same run with and without the flag, while the second person simply times each run. That way the only variable would be the flag.
Yes, they do. We checked the toe in before what I'll loosely call "the experiment". You're right, that could make a big difference. If you check out the next Flag Drag video "Return of Flag Drag" you'll see there were also other factors at play that we later discovered. Thanks for watching!
Are rider weights same? Could impact outcome. But cool test regardless of what people on BROL may say. I do not recall anyone ever saying this was a truly scientific test.
Hi James. Joe weighs about 5 pounds more than I do and that would make a difference. We're just out having some fun. We're never going to make it into "Scientific American". :) Thanks for watching!
Bad experiment. Don't compare two different trikes, two riders, two cameras. Use the same trike, same rider, same camera, on every ride. The only variable should be flag, or no flag. Make multiple runs, alternating with, and without the flag.
Exactly. And the metric should be time between two points, starting from a dead stop and just releasing the brakes. There is a way to see the effects of Rider, Bike, and Flag in 4 runs, or 8 runs if you want to discern interaction effects. I can send you a test matrix if you're interested.
@@jasoningolden2194 Hi Jason! Yep, that would be much more accurate. We're working on a follow-up video, but trying to make it visually interesting. Thanks for the comment!
Fun but way too many variables. You should have switched bikes for one run. Also, is there a possibility that he was riding the brakes? It’s possible that he’s just not as brave as you are on fast downhill tracks. Your weight and weight distribution on your bodies will also skew the results. Try again.
Who cares about what speed you are doing, a Recumbent cycling is for relaxing ride to enjoy your surroundings. If you're going to be racing who's going to need a flag. You need to switch and put the flag on your trike and do the testing again because you really didn't prove anything.
Hey, SFC! We did shoot a second follow-up video in which we switched the flag to the other trike: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-pYf27gxosJ4.html
