Whats the fastest speed you have done



B

Bazza

Guest
What is your fastest speed you have done on ya road bike. I've hit 54kmh on my MTB , but that was
down a steep hill, and I must say, it was terrifying.
 
I've just got a new road bike (a Cannondale) and I've hit 68km/h on it and needed to hit the brakes, because I was ****ting myself just a little bit.

I guess it will take a bit of time to be accustomed to speeds that high.

powinc

ps: What happens if you have a tyre blow out at high speed. I guess it would be very difficult to control if a front tyre blew and not so bad if the back tyre went??
 
77km/h without going out of my way to find a nicer hill...

"Bazza" <[email protected]> wrote in message news:[email protected]...
> What is your fastest speed you have done on ya road bike. I've hit 54kmh on my MTB , but that was
> down a steep hill, and I must say, it was terrifying.
 
81kph on my MTB.
I'm looking for a safer and bigger hill. I was told to try Bunya Mountain.
I was a bit dissapointed the other month when I tried the Bruxner Hwy (comes
down from the tablelands between New England Hwy and Pacific Hwy)
The best I could get was 77kph but that was with 2 rear panniers and a
handlebar bag.
"powinc" <[email protected]> wrote in message
news:J_E%[email protected]...
> I've just got a new road bike (a Cannondale) and I've hit 68km/h on it and needed to hit the
> brakes, because I was ****ting myself just a little bit.
>
> I guess it will take a bit of time to be accustomed to speeds that high.
>
> powinc
>
> ps: What happens if you have a tyre blow out at high speed. I guess it would be very difficult to
> control if a front tyre blew and not so bad if the back tyre went??
>
>
>
> --
 
Bazza wrote:

> What is your fastest speed you have done on ya road bike. I've hit 54kmh on my MTB , but that was
> down a steep hill, and I must say, it was terrifying.

96kph coming back down Fitz's Hill in the Fitz's Challenge. A friend who outweighs me by about 20kg
did 104 down the same hill that day.

Nick
 
"Nick Payne" <[email protected]> wrote in message
news:[email protected]...
> Bazza wrote:
>
> > What is your fastest speed you have done on ya road bike. I've hit 54kmh on my MTB , but that
> > was down a steep hill, and I must
say,
> > it was terrifying.
>
> 96kph coming back down Fitz's Hill in the Fitz's Challenge. A friend who outweighs me by about
> 20kg did 104 down the same hill that day.
>
96, same hill, Canberra Milk Race one year.

[this thread has come up multiple times before]

Jeff
 
"powinc" <[email protected]> wrote in message
news:J_E%[email protected]...
> I've just got a new road bike (a Cannondale) and I've hit 68km/h on it and needed to hit the
> brakes, because I was ****ting myself just a little bit.
>
> I guess it will take a bit of time to be accustomed to speeds that high.

For me, it all depends on how clear it is up ahead. If I can see a long straight line in front of me
- flat out! If it's twisty, I'm much more cautious about my speed.

We hit 79.something kph on the way down from the 1in20 ride last Wednesday. I think my max is 84kph
coming down the Black Spur. I once had 92kph as the max, but after trying to better it, I'm pretty
sure now that it was an error with my Vetta computer.

> ps: What happens if you have a tyre blow out at high speed. I guess it would be very difficult to
> control if a front tyre blew and not so bad if the back tyre went??

I've had front and rear blowouts, but I think they were all under 50kph. All of them were just a
matter of wobbling to a fairly controlled stop, followed by lots of really colourful language
because now I had to walk too far to home/work. I think it depends on how exactly the blowout
happens. The front wheel one was a case of the brake pad wearing through the tyre causing it to pop.
Front end turned rapidly into a shaky mess but not crazy enough that I couldn't just brake and stop.
Bloody tram driver wouldn't pick me up :(

hippy
 
On Fri, 27 Feb 2004 10:30:01 GMT, powinc <[email protected]> Wrote :
> I've just got a new road bike (a Cannondale) and I've hit 68km/h on it and needed to hit the
> brakes, because I was ****ting myself just a little bit.

The "secret" is to put the consequences of disaster out of your mind and concentrate on going
faster. Don't worry about brakes - they only slow you down...:)

>
> I guess it will take a bit of time to be accustomed to speeds that high.

A mate of mine reckons that if you've got things under control you're not going fast enough. I
reckon he's WRONG. Another thing he seems to say a lot is that it seemed like a good idea at the
time...:)

>
> powinc
>
> ps: What happens if you have a tyre blow out at high speed. I guess it would be very difficult to
> control if a front tyre blew and not so bad if the back tyre went??

I've broken 100 a few times on a loaded touring bike coming down from Bradleys Gap towards Corryong
(STEEP and straight). At that speed a suddenly flat tyre would quite probably give you a once in a
lifetime chance to demonstrate that the human body doesn't bounce well and, against a bitumen road
surface, has quite a high coefficient of friction.
ie. You die with lotsa broken bits and even more missing skin. Do try not to think about it...:)

--

Humbug
 
Nick Payne wrote:
>
> A friend who outweighs me by about 20kg did 104 down the same hill that day.

Second or third time someone has said something like that... you don't accelerate down a hill any
faster or have a higher top speed if you weight more.

In fact you'd probably be slower on both counts if you weighed more as you'd likely have more
frontal area, which equals more wind resistence.
 
Bazza wrote:
> What is your fastest speed you have done on ya road bike. I've hit 54kmh on my MTB , but that was
> down a steep hill, and I must say, it was terrifying.
>
>
Haven't we done this thread a whole lotta times before?

Anyway.

84.9 kph down the big hill with a tail wind on the Great Ocean Road, Victoria, Australia, Jan 1996.

Equipment used: otherwise stock 1990 GT Karakoram MTB, but with Cinelli Eubios 44cm drops and Shimmy
600 bar-end shifters; heavy home-made rack-top bag on alu Korean-made (many fine things are made in
Korea, but that's another story) generic rear rack. Speed recorded by v beaten-up Cateye "Astrale"
cycle 'poot. Li'l sis on her road bike, who I was touring with, witnessed this. She said she only
hit 70 kph or so. I don't think downhill speeds justifies riding a heavy bike.

I claim this as a World Record in the "Bicycle/Bicycle Idiots/Mountain Bikes retrofitted with drop-
bars" class.

And so on.

Ooops. Meant to be top speed on your road bike. My road bike is in several places (frame: lower left
storage space, wheels: upper right storage space, running gear: attached in hybridised form to
- commuter bike,
- shopping bike,
- various boxes of bike bits...

Well... s... Yeah...

Anyway,

pppppppp
 
"Matt" wrote:

> Nick Payne wrote:
> >
> > A friend who outweighs me by about 20kg did 104 down the same hill that day.

> Second or third time someone has said something like that... you don't accelerate down a hill any
> faster or have a higher top speed if you weight more.
>
> In fact you'd probably be slower on both counts if you weighed more as you'd likely have more
> frontal area, which equals more wind resistence.

As a heavy bloke, I can assure you that we've got the advantage downhill. Even without
slipstreaming, I've got to brake to avoid overtaking other cyclists.

Certainly, heavier individuals have greater surface area. But that is proportionally less that the
increased mass. Surface area increases less than volume does - it's simple geometry.

That trick with the volume:surface area ratio is why animals in cold climates are usually larger
than those in warm ones (samples from the same species).

John
 
"John Henderson" <[email protected]> wrote in message
news:[email protected]...
> "Matt" wrote:
>
> > Nick Payne wrote:
> > >
> > > A friend who outweighs me by about 20kg did 104 down the same hill that day.
>
> > Second or third time someone has said something like that... you don't accelerate down a hill
> > any faster or have a higher top speed if you weight more.
> >
> > In fact you'd probably be slower on both counts if you weighed more as you'd likely have more
> > frontal area, which equals more wind resistence.
>
> As a heavy bloke, I can assure you that we've got the advantage downhill. Even without
> slipstreaming, I've got to brake to avoid overtaking other cyclists.
>
Maybe you have better technique/position than them?

> Certainly, heavier individuals have greater surface area. But that is proportionally less that the
> increased mass. Surface area increases less than volume does - it's simple geometry.
>
The increased mass shouldn't matter - what about Galileo's experiments?

Jeff
 
"Jeff Jones" <jeff@cyclingnews-punt-com> wrote in message
news:[email protected]...
>
> "John Henderson" <[email protected]> wrote in message news:[email protected]
> berlin.de...

> > Certainly, heavier individuals have greater surface area. But that is proportionally less that
> > the increased mass. Surface area increases less than volume does - it's simple geometry.
> >
> The increased mass shouldn't matter - what about Galileo's experiments?
>
(replying to own post)

Actually John I'll give you this one, as cycling is not the same as free falling in a vacuum ;-)
Applying the following cycling descending equation:

s = sqrt [-giM/kaA]

s=terminal velocity g=gravitational constant i = grade of the road M = mass of cyclist ka = air
resistance coefficient A = frontal surface area of cyclist + bike

So taking out all the constants, terminal velocity is proportional to M/A, and as you said heavier
cyclists have proportionately more M than A so they should go faster!

Jeff (chastising self. never would have thought I did 2nd year physics at uni)
 
On Fri, 27 Feb 2004 19:15:06 +1000, "Bazza" <[email protected]> wrote:

>What is your fastest speed you have done on ya road bike. I've hit 54kmh on my MTB , but that was
>down a steep hill, and I must say, it was terrifying.

72 kph on a single speed 28" Massey, coming down Baker St towards Luck St. I chickened out as the
T-intersection got closer. Mind you, the pedal activated friction brakes off the back wheel have a
bad tendency to lock up under thos circumstances.

---
Cheers

PeterC

[Rushing headlong: out of control - and there ain't no stopping]
[and there's nothing you can do about it at all]
 
"Bazza" <[email protected]> wrote:

>What is your fastest speed you have done on ya road bike. I've hit 54kmh on my MTB , but that was
>down a steep hill, and I must say, it was terrifying.
>

77 Down Burmingham Rd. Mt. Evelyn on and old steel MTB no suspension would have been 80 if I hadn't
tested the brakes to make sure I'd stop at the bottom before Swansea rd.

May all your cycling adventures be with a tailwind,

Neil.
 
On Fri, 27 Feb 2004 10:30:01 +0000, powinc wrote:

> ps: What happens if you have a tyre blow out at high speed. I guess it would be very difficult to
> control if a front tyre blew and not so bad if the back tyre went??

Has anyone ever had an actual blowout?

I have, but that was after inflating my tyres with a petrol-station pump[1]. They did feel a bit
hard, and would take pressure to 85psi, so when they went off like a gunshot 100m later, it was
obvious user-error on the pump was the cause.

Interestingly, the tyre was mostly ok, but the tube had a 30cm gash in it. I replaced the tube, but
the tyre had a bit of a 5cm bulge on one side. Having no spare tyre, I rode on it for another 20km
or so until I passed a shop. Once I had a spare tyre, I kept using the lumpy tyre for another
hundred km or so... another bulge developed just up from the first, and then the next day (was
touring) a third bump formed. At this point we swapped over the tyre for the spare.

-kt

[1] Inflating presta tubes with a schrader valve adapter. I think the meter on the pump was
measuring the pressure inside the valve adapter, not the tube.

--
Kingsley Turner, (mailto: [email protected]) http://MadDogsBreakfast.com/ABFAQ -
news:aus.bicycle Frequenly Asked Questions
 
"John Henderson" <[email protected]> wrote in message
news:c1o6kq$1l2s5v$1@ID-
> "Matt" wrote:
>
> > Nick Payne wrote:
> > >
> > > A friend who outweighs me by about 20kg did 104 down the same hill that day.
>
> > Second or third time someone has said something like that... you don't accelerate down a hill
> > any faster or have a higher top speed if you weight more.
> >
> > In fact you'd probably be slower on both counts if you weighed more as you'd likely have more
> > frontal area, which equals more wind resistence.
>
> As a heavy bloke, I can assure you that we've got the advantage downhill. Even without
> slipstreaming, I've got to brake to avoid overtaking other cyclists.

Yeah, I notice that I always catch the ligher riders when rolling down hills... maybe I just put in
an extra pedal stroke or two at the top? :)

hippy
 
"Jeff Jones" <jeff@cyclingnews-punt-com> wrote in message
news:403fa63b$0$311
> So taking out all the constants, terminal velocity is proportional to M/A, and as you said heavier
> cyclists have proportionately more M than A so
they
> should go faster!

Thanks for that Jeff.. I'm glad I wasn't "imagining" going faster than the others!

hippy
 
Matt <[email protected]> wrote in message news:<[email protected]>...
> Nick Payne wrote:
> >
> > A friend who outweighs me by about 20kg did 104 down the same hill that day.
>
> Second or third time someone has said something like that... you don't accelerate down a hill any
> faster or have a higher top speed if you weight more.
>
> In fact you'd probably be slower on both counts if you weighed more as you'd likely have more
> frontal area, which equals more wind resistence.

If the frontal area is the same, then the heavier rider will have a higher terminal velocity. Go to
www.analyticcycling.com and try some different numbers in the Speed given Power page.

Ritch

PS. 85.1 down F'tree Gully Road east of Jells Road...
 
On Sat, 28 Feb 2004 09:07:34 +1100, kingsley
<[email protected]> wrote:

>On Fri, 27 Feb 2004 10:30:01 +0000, powinc wrote:
>
>> ps: What happens if you have a tyre blow out at high speed. I guess it would be very difficult to
>> control if a front tyre blew and not so bad if the back tyre went??
>
>Has anyone ever had an actual blowout?
>
>I have, but that was after inflating my tyres with a petrol-station pump[1]. They did feel a bit
>hard, and would take pressure to 85psi, so when they went off like a gunshot 100m later, it was
>obvious user-error on the pump was the cause.

I haven't, but was riding with my sister when her front went off like a gunshot. This was about 6 km
into a ride. The tyre was rather old and perished, but was carrying 60 psi at the start of the ride.

---
Cheers

PeterC

[Rushing headlong: out of control - and there ain't no stopping]
[and there's nothing you can do about it at all]