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Poll: Who thinks some of these "Top Speeds" are inflated?(33 posts)

Poll: Who thinks some of these "Top Speeds" are inflated?Kristin
Oct 21, 2003 11:43 AM
Especially the top speeds on flats poll. It seems to me that some of these claims are a little grandious! Am I mistaken?
We learned from the master...Marketing Dept
Oct 21, 2003 11:59 AM
position looks a little cramped...oh sorry wrong response (nm)ColnagoFE
Oct 21, 2003 12:30 PM
how dost thou dare to asketh such a question....funknuggets
Oct 21, 2003 12:01 PM
Honestly, I think that most of these are genuine. I cannot attest that I have gone as fast as some, but I have gone faster than others. I agree that it seems insane that a "peleton" would be closely knit together at 38mph. A paceline... maybe... but you know what I mean. There could be an excessive tailwind or a downhill, or many factors to help inflate such speeds. On a long straight downhill in southern missouri (If you've been around Branson you know what I mean), I once saw 51 mph on my avocet... so are they either unlikely or unbelievable... not really. I agree on the flats... perhaps... but I give them the benefit of the doubt.

No one here is making aarontoy type claims. If they did, you know the whole board would be on him in a second. Believe me, Id swear people are just waiting to pounce.

Chris
RBR(Penthouse) forum. I never considered my 69mph fast butDave Hickey
Oct 21, 2003 12:09 PM
I'm sure some are inflated:-)
re: yes you arecyclopathic
Oct 21, 2003 12:20 PM
though I don't keep tap on "fastest" the 60mph on downhill in full tack and 35-40mph max in sprint (esp on false flat with tailwind or in pack) are not unreal. I had seen it and I've been paced by tandem on flats at 32-35mph. Keep in mind there're alot of big burly animals racing cat1-3 who would have no problem go over 40mph in sprint.
you think? I really did do 200 in my dreams!ColnagoFE
Oct 21, 2003 12:29 PM
56 in real life on a bike.
I do believe that guys have gone by me at some of those speedsbill
Oct 21, 2003 12:34 PM
Every day, at Hains Point in DC, guys go round and round in circles really, really fast. It's a loop of maybe 3 mi (interestingly, as many times as I've gone around it, I don't know the distance). But it draws out some of the big local sprinters as well as some incredibly fast older guys who don't even race anymore, and they sprint every lap. The leadout usually goes like 30-32 (almost always into th wind), and then they sprint. I can sit in on the leadout, but then the big boys are gone and I'm out in the wind and that's about it for me, so I'm not pacing anyone at 38-40, but I think that they hit that.
LOL. That reminds me of the old guy at Busse WoodsKristin
Oct 21, 2003 1:09 PM
Has anyone else seen this guy?!? I wonder sometimes if he has a twin and they both ride at the same time, in the same clothes, on identicle bikes, but starting from opposite sides of the loop. Its a 7.8 mile loop and I'll go mabey 3 miles before he passes me again. That comes out to 33.42MPH average. Is my math correct? There is also another guy there, has darker skin and dark hair, with a muscular, compact frame (body), who would pass me about every 5 miles. That would put him at about 20MPH average, which is much more believable than the other guy.
Fact of life for old guysIronbutt
Oct 21, 2003 1:18 PM
The older I get, the faster I was. I'm almost 57, and by the time I reach 60, I will have been really fast!
Old guys are just better at shortcuts. (nm)TFerguson
Oct 21, 2003 2:14 PM
I do believe that guys have gone by me at some of those speedsdcboomer
Oct 21, 2003 3:27 PM
Almost exactly 3.2 miles. Are you sure those guys are going all the way out to The Awakening, and not taking the bus cut through??? :-) :-)
Trust me...... I remember the day wellMR_GRUMPY
Oct 21, 2003 12:35 PM
It was one of the few "high points" of my career. It was in 1996 or 97. State Championship RR. 100K. I managed to pull out a third place in the masters race.
I don't necessarily think so.Alex-in-Evanston
Oct 21, 2003 12:45 PM
My fastest time on a flat came in the sprint lane of a velodrome, 38mph. I figured I could have bumped it up a notch or two if I wasn't spun out in a 50/15.

I'm no great shakes either, just a recreational cyclist who races from time to time. I think it's perfectly plausible for a Cat 4 nobody to hit 38mph with the right leadout.

Alex
Doesn't really matter.MXL02
Oct 21, 2003 12:48 PM
No matter how fast you say you can go...

there's always someone faster.
Keep in mind...funknuggets
Oct 21, 2003 12:51 PM
this is a specific point in time that is uniquely altered by conditions. So, on the right downhill, being passed by the right vehicle, in the right draft, with the right tailwind... the most incredible results could happen to riders with but a tidbit of fitness. We arent talking Boardman type efforts, or Armstrong efforts over an extended period of time.

Just saying they have gone that fast is not a measure of condition, skill or power, it is more a factor of the situation (which is not nearly as reproducable, which is why pros are... pros). So, I pretty much believe these speeds as realistic.

Chris
to me, Lance does the impossibleDougSloan
Oct 21, 2003 12:53 PM
I think your perspective depends upon your experience and fitness level yourself. To me, Lance averaging 34 mph in a time trial is totally unreal. If I did not know better, from my own experience, I'd think is was a pure lie. The best I can do on flat ground is merely hit 36 mph instantaneously, then die a horrible death and crawl for a while. My 64 mph down hill is also easily surpassed by pros or larger riders. It takes a darn big hill, unlike anything in the midwest, to get there, too.

I haven't seen any claims, short of a newbie time trialing at 31 mph, that seemed totally incredible.

Doug
c'mon Doug...funknuggets
Oct 21, 2003 1:08 PM
Obviously you didnt see that my 51 in a 35 speeding ticket was on my LOOK... haha.

Man, with all your experiences in mid missouri, Im amazed that you didnt spend more time climbing in and out of Missouri River valleys... like towards Hermann. Some steep puppies can get you close to 50 in a FLASH. There is one outside JC going up to Bluffmont estates that I would love to open it up, but that damn 90 degree turn at the bottom would be interesting.

Too bad they end so quickly. I wonder what someone could do on some of those San Fran hills if there werent so many cross streets!!! That would be fun.

Chris
I was thinking something similarKristin
Oct 21, 2003 1:14 PM
I've never tried to get the bike up to 64MPH before, so I don't know how much of a difference there is between 50MPH and 64MPH...though I supose its 14MPH. Anyway, all the hills we have here are steep too. Not long at all, but VERY steep. I can reach 50MPH in no time at all.
huge difference between 50 and 60DougSloan
Oct 21, 2003 1:44 PM
I go 50 nearly every time I get beyond the Fresno City limits. No big deal. Can't recall what I did in the midwest, but 50, I'd think, is about it. I have to try really, really hard to hit 56 mph on the same hills, where 50 is a no brainer.

64 mph is down a 17 mile long hill, starting at 5,000 feet elevation (thinner air = higher speed), fairly straight, good pavement -- all the ingredients for high terminal velocity. However, the amazing statistic on that hill is that you can remain over 50 mph for 10 minutes! I'd bet there are few places on the planet where that's possible.

To demonstrate, I ran some numbers at www.analyticcycling.com. It would take the equivalent of 3,000 watts power to go 60 mph on flat ground at sea level. It would take only 1800 watts to hit 50 mph, both sustained long enough to hit that terminal speed. 64 mph is the equivalent of 3700 watts.

As you can see, the difference in power required to go fast is huge, requiring TWICE the power at 64 mph than 50. Doesn't matter that gravity is effectively supplying the power, what you are comparing, really, is the relative wind resistance. Make sense?

Doug
there are a few places like that in COColnagoFE
Oct 21, 2003 1:57 PM
not as many that are straight enough to maintain that speed though. Fremont pass comes to mind as one that you are 50+ for 10 minutes or more. nice wide road too. the only thing that slowed me down was the car traffic.
Indeed ...Humma Hah
Oct 21, 2003 2:07 PM
... 2.1x the power is closer to the truth.

Kristen, air resistance is the primary drag on a bike at high speed, and air resistance, and the force to overcome it, increases with the square of air velocity. Power is force times speed, and that works out to mean you multiply by velocity again so that power required increases by velocity cubed.

64/50= 1.28. 1.28^2 = 1.64, so the force of wind resistance is 1.64x as high at 64 mph as at 50 mph. So instead of a hill grade of 10% to go 50 mph, you might need a grade of something like 16% to go 64 mph. Either that, or you scrunch down into the tightest possible tuck and just drop your wind resistance that way. That's how I got my nutty-high speeds.

The power required at 64 mph is 1.28 x 1.64 = 2.10x as high as the power at 50 mph.
good to confirmDougSloan
Oct 21, 2003 2:15 PM
Nice to see a confirmation from a real scientist, rather than us hacks. ;-)

Doug
Ouch! Thatsallatamath...Kristin
Oct 21, 2003 2:26 PM
So basically, your saying its lots harder to go 64MPH down hill than it is 50MPH? That makes sense and I was wondering about that. Question. To start from 0MPH, how many feet would it take to reach 64MPH decending on a pristine 16% grade road?

We've got lots of big grade out here, just not long, big grade. Around Chicagoland, you can find 20% for 1/4 of a mile. Stuff like that. In Wisconsin & Indiana, you can find 20% for 1/2 mile to a mile. I was decending about 300 feet over a mile and reached 50MPH very quickly. Then I applied the brakes since it seemed like I'd hit 70 if I didn't. But you know. That's how it "felt."
Yep. I've seen 50+ in 0.6 miles.KG 361
Oct 21, 2003 4:43 PM
Moor's mtn road. Checked it on my Topo USA-top is @ 16%, avg grade 8%. About 3/4 of the way down I've seen 50+, then it's time to nail the brakes. 'Friggin stop sign!
Of course, I'm on a Look, too. =) nmKG 361
Oct 21, 2003 4:44 PM
World record top speed on flat ground is over 160 mph ...Humma Hah
Oct 21, 2003 1:04 PM
... with enough gearing and something breaking the wind, or a strong enough tailwind, anything up to that is credible.

Downhill speeds in the 60 mph range are easily credible, and also evidence of a certain level of insanity. Speaking from experience.
DH speed is just the tightest tuck & no brakes.......so what? nmCat 3 boy
Oct 21, 2003 1:27 PM
60MPH down a hill is very doable, if you are fearlesshudsonite
Oct 21, 2003 3:11 PM
Did 60MPH down a big hill 25 years ago when I thought I was invincible. Now that I know better, I won't go faster than 40MPH.

Experience teaches you how fragile life really is.
Tight tuck, no brakes, big huevos, no brains?Straightblock
Oct 21, 2003 3:33 PM
I did a lot of things at age 22 that I wouldn't do at 48.

Many years ago, I remember seeing a couple of riders near me just sit up and drop out of the lead group descending Townes Pass, a 60mph, wide, smooth, WFO downhill in the old Death Valley to Mount Whitney stage race. Most people had never gone that fast before, and to do that kind of speed in a pack while wearing a leather hairnet was pretty frightening to some.
The older I get, the faster I was. nmContinental
Oct 21, 2003 5:27 PM
Sorry Ironbutt, I responded before reading nmContinental
Oct 21, 2003 5:40 PM
My guess is we round upward then add 1 or 2 MPHbimini
Oct 22, 2003 7:16 AM
Some of the MPH are believeable. I know my speedometer runs a slightly slow and have been stomped in sprints in a flat oval race where my speedometer showed a max speed of 35 MPH.

I watched the finish of a pro road race with a long slight downhill grade (3-5%) in a no wind situation. The race officials had a radar gun on the winner (team 7up) and announced a top sprint speed of 55 MPH on the PA. It was a packed field at the end of this race and the winning teams had a full group to wind up thier sprinters and slingshot them in across the finish line. Great to watch, but happens fast.