Todzilla

Map My Ride has my top speed for each of my last three days as over 60 MPH, with the highest speed reported as 68mph. There were some very steep hills and I let 'er rip a few times, but surely this is a misread from the app?

A few other 45 MPH readings seem reasonable.

Thoughts?

Jarrett2

Nope, you just rock.

CNC2204

Apperently 60 is childsplay compared to 138.752 mph.

Lazyass

You don't have a bike computer?

Todzilla

Nope, just a smartphone with the Map My Ride app. Ain't no way I could get over 50 and not disintegrate just from the friction of air molecules alone!

caloso

68 is flying, but definitely possible on a long, steep straightaway.

cthenn

Well, then if you don't have a computer that reads speed based on wheel rotation, you won't know the truth. I have gotten to 60 just once, and it was on a very wide, straight ~7% road with good pavement in a monster tailwind, and that was pretty scary. A sub 16-lb bike gets pretty skittery at those speeds! It is very possible (professionals do it regularly), but I wouldn't trust a smartphone GPS-based app to provide very accurate numbers (or as accurate as an actual computer will).

Lazyass

I wouldn't even trust a smartphone to be accurate. And they look stupid mounted on a bike. You can get a basic computer for twenty bucks.

kini62

Since when is the GPS in a smartphone less accurate than a stand alone GPS or some bike computer achieving its data by some wheel/tire size calculation.

My phone reads nearly identically over the same route every time. Varies around .01-.02 miles over the 11 mile ride.

But the only way the OP could hit over 60mph would be coasting down a long and very steep hill.

ravenmore

I once hit 62 mph drafting a truck a long time ago. It was more of a challenge spinning the cranks fast enough than anything else - crazy high cadence to hit that.

coolcamaro12

RR3

I have done over 60 mph twice.

The first time required surgical removal of the right, retracted testicle while the 66 mph jaunt lost me my left one. I am now lacking the motivation to do such stupid things.

banerjek

Over long distances, either should be accurate. Top speeds recorded over short distances are another matter entirely. I'd like to see what stretch of road he hit 68 on. Since this was done via app, there should be data for the entire ride that verifies whether or not this value makes sense. I personally doubt anyone who would need to ask this question has hit 68. That's truly crazy fast and requires a long steep, smooth, and relatively straight road.

SpeshulEd 

It's possible, but it's also possible that your GPS lost track of you due to hills or trees or whatever else and when it picked you up again you were further down the hill, causing a skip in the GPS data resulting in a faster than normal speed.

VinceB

Unless there's data showing a proper build-up to 68, followed by slowing down, I'd say it's an error in the GPS speed reading causing a speed spike. Happens to me all the time when I'm using GPS on my phone to record speed, though not quite that high.

Jeremy_S

I used to use a bike computer and my strava app. Strava was always within a tiny margin of error for the ride even on single track with a lot of switchbacks so I just ditched computers and stuck with the iPhone to keep track.

That said, last week, I hit 102.54 mph for appx 220 feet on flat ground.

Obviously a glitch (and my only one I've ever had with Strava) but for about 10 miles it made my average mph look like I was a freakin beast

Lazyass

I don't trust them. I don't like how slow the mph's are to change compared to a bike computer.

Diablito

I hit 71mph going down hill on a full suspension in Plattekill, ny. Was like holding on to a jack hammer. Adrenaline Rush was Amazing

Bad_Luck_Blonde

if you want an example

for me I use both an node 1.1 with wheel sensor, and an iphone running strava. for my ride yesterday my computer read a max of 38.2, strava read a max of 52.3 this seems like a big difference, but it comes down to a few factors. The wheel is spinning fast enough that it sends a ping to the computer multiple times a second. the gps likely records your position every second and then divides your distance by your time to determine speed, so they essentially function off of the same principle, looking at short intervals of distance and time to determine speed.

Your wheel will always cover the same distance per rotation (unless you have mad drifting skills) whereas the gps is only accurate to 50-70 feet if you are in an area with trees. over four seconds a cyclist traveling 20mph, will cover roughly 120 feet. the margin for error is significant per measurement. over the bike ride this will cancel out as the over estimates and underestimates average out to your overall distance/time.

dedicated cycling gps's have a better system that looks at past and previous values and has better equations to detect erroneous values.
Your phone is not an accurate device for measuring top speed. It is however a decent device for tracking your total distance and elevation.

Johnny Rad

I for one vote absolutely not.

If you have to ask, you didn't.

IMHO and experience, 55mph feels worlds different than 45mph. Forties are child's play. Fifties require way more attention.

For the record, I've "only" topped out at 57 and change.

Johnny Rad

I could be dead wrong. It happens!

Where were you? What road? Conditions?

Homebrew01

Did you need to change your shorts at the bottom of the hill ??
I have done 50+ several times, and that is pretty attention getting.

Todzilla

Road conditions: very steep, like 8% grade! but too curvy for sustained stretches. As Banerjek suggested, I highly doubt the burst speed calculation. I was going really fast, but I'd be shocked if I was going much over 45. The only thing that made me think it was possible was getting a 60+ reading each of the three days I rode it.

And, while I'm a regular 20-mile a day commuter on my CAAD, my 57 year old legs aren't capable of those speeds, even with a huge gravity assist.

Shimagnolo

I've hit 55mph only a handful of times:
- Once on a 14-16% mtn descent.
- Once coasting down a 12% grade with a tailwind from hell behind me.
- Once pedaling like hell down a 9% grade with a brisk tailwind.

GlennR

My first ride ended with a long downhill. I quickly ran out of gears and let Sir Issac Newton take control.

It was scary fast and at the bottom I asked my son, who had a computer, said we his 48mph.

I rather not go that fast on a road that i never rode before again.