Yet Another Cycling Forum

General Category => Audax => Topic started by: CrazyEnglishTriathlete on 20 December, 2017, 07:06:19 am

Title: Latest start to complete a 100km ride before midnight
Post by: CrazyEnglishTriathlete on 20 December, 2017, 07:06:19 am
Seriously JPO after a bad day at the office yesterday decided to do the planned 100km ride even if I had a late start.  Working in the Hague means no hills, so left at 7.39pm and was back at the late night store after a round trip to Mijdrecht to pick up supper at 11.43pm.  That made me wonder what the latest start to finish a 100km ride was.  (Not thinking about a PBP where the first 100km can be a mad dash, but the ride isn't finished until 2 or 3 days later).
Title: Re: Latest start to complete a 100km ride before midnight
Post by: psyclist on 20 December, 2017, 09:15:16 am
71 people have read this thread and nobody replied yet. Maybe it is not just me who is trying to get their head around the question.

From an audax perspective, the latest start would be just before midnight for the ride to be counted for the current day. But I'm sure you know that.

If it is from a desire to finish before midnight, then surely it would depend upon your speed potential, prevailing weather and terrain.

Could you expand on the question?
Title: Re: Latest start to complete a 100km ride before midnight
Post by: jsabine on 20 December, 2017, 11:32:52 am
The reductive answer is presumably 20:39:59, as if you start any later and still finish before midnight, you must have averaged more than 30km/h.

How much earlier do you need to be comfortable? In my case, probably about 1800 ...
Title: Re: Latest start to complete a 100km ride before midnight
Post by: dim on 20 December, 2017, 11:52:45 am
Just a general guideline ...

If you are cycling from a point, and ending at the same point, (i.e. in a loop), the elevation gain will be the same as the elevation downhill. If there is headwind for half the way, there will be tailwind for the other half, so it balances out

depending on your fitness, you should finish a 100km ride in under 4 hrs (25 Km/hr) if you dont stop to rest for a lengthy period, and assuming you have no mechanical issues / punctures etc ...

obviously, if you are fitter, you will finish much sooner, but when I plan a new ride, I estimate the time based on 25 Km/hr .... if I finish sooner, it's a bonus
Title: Re: Latest start to complete a 100km ride before midnight
Post by: Greenbank on 20 December, 2017, 12:10:46 pm
If you are cycling from a point, and ending at the same point, (i.e. in a loop), the elevation gain will be the same as the elevation downhill. If there is headwind for half the way, there will be tailwind for the other half, so it balances out

Only sometimes.

Not all climbing is the same. A rollercoaster road that climbs/dips 5m at a time (so that you can maintain momentum) is much nicer than a series of big steep climbs followed by descents with a sharp turn at the bottom, etc. A strong sidewind for the entire ride is way more tiring than a still day. Wind direction and strength changes over time. etc.

Closest I've come is doing a 100km ride starting at just after 5pm, would have finished that in under 5h.
Title: Re: Latest start to complete a 100km ride before midnight
Post by: Kim on 20 December, 2017, 12:28:42 pm
Only sometimes.

Not all climbing is the same. A rollercoaster road that climbs/dips 5m at a time (so that you can maintain momentum) is much nicer than a series of big steep climbs followed by descents with a sharp turn at the bottom, etc. A strong sidewind for the entire ride is way more tiring than a still day. Wind direction and strength changes over time. etc.

Also, you ideally want the headwind to happen while you're climbing, as you'll be travelling at a lower speed and less affected by it.
Title: Re: Latest start to complete a 100km ride before midnight
Post by: Karla on 20 December, 2017, 12:35:48 pm
[revises loop integrals from first year maths lectures]
Title: Re: Latest start to complete a 100km ride before midnight
Post by: Samuel D on 20 December, 2017, 12:54:30 pm
If you are cycling from a point, and ending at the same point, (i.e. in a loop), the elevation gain will be the same as the elevation downhill. If there is headwind for half the way, there will be tailwind for the other half, so it balances out

Even if the wind is steady in strength and direction (it rarely is over several hours of riding), it doesn’t “balance out” because aerodynamic drag varies with the square of the relative wind speed. This means you always pay a penalty if your airspeed varies during the ride, as it must with wind and hills.

For the same reason, time trialists ride harder on climbs despite the biological cost of that uneven power output.
Title: Re: Latest start to complete a 100km ride before midnight
Post by: frankly frankie on 20 December, 2017, 02:21:15 pm
Everyone rides harder on climbs don't they?
Title: Re: Latest start to complete a 100km ride before midnight
Post by: Ian H on 20 December, 2017, 02:46:35 pm
Everyone rides harder on climbs don't they?

Except elderly time-trialists using power-meters.
Title: Re: Latest start to complete a 100km ride before midnight
Post by: Samuel D on 20 December, 2017, 05:27:28 pm
Everyone rides harder on climbs don't they?

Yes, but often for the wrong reasons (or just for fun). If what dim said was true, the fastest way around a course would be constant power.
Title: Re: Latest start to complete a 100km ride before midnight
Post by: hillbilly on 20 December, 2017, 05:39:00 pm
71 people have read this thread and nobody replied yet. Maybe it is not just me who is trying to get their head around the question.

Tru dat. 

Perhaps CET's bike changes back into a pumpkin at the chimes of midnight? 
Title: Re: Latest start to complete a 100km ride before midnight
Post by: Whitedown Man on 20 December, 2017, 05:42:17 pm
TBF to CET, his thread title is completely clear
Title: Re: Latest start to complete a 100km ride before midnight
Post by: mattc on 20 December, 2017, 05:52:51 pm
TBF to CET, his thread title is completely clear
Unfortunately the detailed description made things rather unclear (as did posting it under "Audax", which as pointed out early on, brings max speed limits into the puzzle ... )

Still, it has created some entertaining debate on a range of topics, including a suggestion that flat rides are no easier than hilly ones. Or something ...
Title: Re: Latest start to complete a 100km ride before midnight
Post by: Frank9755 on 20 December, 2017, 10:45:31 pm

Also, you ideally want the headwind to happen while you're climbing, as you'll be travelling at a lower speed and less affected by it.

Are you sure?
Headwind on the climb means you'll be in it for more hours, going very slowly (relative to the ground, but quicker relative to the air), then you'd have tailwind on the descent when you don't need it!
If I had the choice I'd go for for tailwind on the climb / headwind on descent to even my speed out.  Would be faster overall
Title: Re: Latest start to complete a 100km ride before midnight
Post by: Kim on 20 December, 2017, 10:50:34 pm

Also, you ideally want the headwind to happen while you're climbing, as you'll be travelling at a lower speed and less affected by it.

Are you sure?

No.


Quote
Headwind on the climb means you'll be in it for more hours, going very slowly (relative to the ground, but quicker relative to the air), then you'd have tailwind on the descent when you don't need it!
If I had the choice I'd go for for tailwind on the climb / headwind on descent to even my speed out.  Would be faster overall

I was saving the tailwind for the flatter part of the ride, when it's more useful.  :)
Title: Re: Latest start to complete a 100km ride before midnight
Post by: postie on 21 December, 2017, 06:55:05 am
What about crossing time zone's  :demon:

I.e. a straight out 100km

Only trying to help.
Title: Re: Latest start to complete a 100km ride before midnight
Post by: frankly frankie on 21 December, 2017, 10:07:07 am
Headwind on the climb means you'll be in it for more hours, ...

But to some extent sheltered from it (you're in the lee of the hill).
Title: Re: Latest start to complete a 100km ride before midnight
Post by: grams on 21 December, 2017, 10:58:27 am
What about crossing time zone's  :demon:

There's a *pause for Googling* three and a half hour time difference at the border between Afghanistan and China. I reckon that's enough to time for a fast rider to do a 100 km. Yes, it's quite hilly there, but as we've learnt on this thread, hilly rides are no slower than flat rides.

So the answer is midnight in China.
Title: Re: Latest start to complete a 100km ride before midnight
Post by: grams on 21 December, 2017, 11:21:13 am
If the ambition is to start and finish on the same day then you need to set off at 23:59:60 on the day of the leap second.

(Edit: I seem to be replying to a deleted comment)
Title: Re: Latest start to complete a 100km ride before midnight
Post by: hillbilly on 21 December, 2017, 11:21:40 am
I hope people are taking account of leap seconds when coming up with their answers.

https://en.wikipedia.org/wiki/Leap_second

Never mind helmet pictures.  This question highlights the weighty areas that could stimulate discussion and controversy in Arrivee.   
Title: Re: Latest start to complete a 100km ride before midnight
Post by: hillbilly on 21 December, 2017, 11:22:09 am
If the ambition is to start and finish on the same day then you need to set off at 23:59:60 on the day of the leap second.

(Edit: I seem to be replying to a deleted comment)

Re the edit.  I changed it because I wasn't sure of the maths!  Professional vanity.
Title: Re: Latest start to complete a 100km ride before midnight
Post by: fuaran on 21 December, 2017, 11:26:25 am
What if an audax crosses the international date line? Most of it is in the ocean, but you could use a pedalo...
Title: Re: Latest start to complete a 100km ride before midnight
Post by: hillbilly on 21 December, 2017, 11:32:25 am
Regulations state that AUK events are cycle rides.  So I suspect a pedalo might be ruled out as it is not a cycle. 

That said, I don't think its been tested and so I would suggest someone seeks clarification from the relevant AUK official.

Of course, a scuba mask and a cycle might be possible, but I suspect completing the ride within time limits might be challenging.
Title: Re: Latest start to complete a 100km ride before midnight
Post by: Delph Cyclist on 21 December, 2017, 12:43:09 pm
TBF to CET, his thread title is completely clear

Well I for one didn't understand the question, or at least, felt that the question wasn't complete, but at least it gives the opportunity to answer lots of different questions instead.

The Plains 300 starts at 23:00, which is only a hour before midnight.  However, that's for a 300km and I don't know what adjustments you need for a 100km.  The event used to start it at 00:01 giving us a massive 23 hours 59 minutes before midnight (plus or minus any leap seconds you want to take into consideration and note that I am ignoring relativistic effects).  Don't tell anyone, we actually set off at 00:00.
Title: Re: Latest start to complete a 100km ride before midnight
Post by: mattc on 21 December, 2017, 12:48:23 pm
and note that I am ignoring relativistic effects
Oh dear  :facepalm: Schoolboy error!
Title: Re: Latest start to complete a 100km ride before midnight
Post by: dim on 21 December, 2017, 01:47:05 pm

Also, you ideally want the headwind to happen while you're climbing, as you'll be travelling at a lower speed and less affected by it.

Are you sure?
Headwind on the climb means you'll be in it for more hours, going very slowly (relative to the ground, but quicker relative to the air), then you'd have tailwind on the descent when you don't need it!
If I had the choice I'd go for for tailwind on the climb / headwind on descent to even my speed out.  Would be faster overall

I agree 100% ....

a course/loop is much easier with the wind behind your back on the steepest hill sections .... then downhill into the headwind.

I have several regular routes that I ride, and I ride them both clockwise and anti-clockwise

I record all my rides (not commuting) on a Microsoft Access Database and I record info such as wind speed, wind direction, heartrate, cadence, ave speed, elevation etc etc

and the results always show that I am faster on the same routes (with similar wind speed and direction), when I do the steepest parts with a tail wind.

A pretty nifty database .... I check the wind speed and direction, and I can filter previous results based on the info, then choose a route for either a fast time, or a slower/ harder training ride
Title: Re: Latest start to complete a 100km ride before midnight
Post by: Ajax Bay on 21 December, 2017, 06:07:01 pm
"A pretty nifty database"
Please allow me to add my admiration to that of those silent dozens who have read your post.
Title: Re: Latest start to complete a 100km ride before midnight
Post by: mattc on 21 December, 2017, 06:43:49 pm
"A pretty nifty database"
Please allow me to add my admiration to that of those silent dozens who have read your post.
+1

(sometimes silence doesn't mean indifference - it's cos we're lost for words :) )
Title: Re: Latest start to complete a 100km ride before midnight
Post by: dim on 21 December, 2017, 09:09:42 pm
"A pretty nifty database"
Please allow me to add my admiration to that of those silent dozens who have read your post.

Yea .... I never went to posh school and don't think in English .... it's ghetto talk from South Africa  8)
Title: Re: Latest start to complete a 100km ride before midnight
Post by: ElyDave on 22 December, 2017, 07:19:50 am
Regulations state that AUK events are cycle rides.  So I suspect a pedalo might be ruled out as it is not a cycle. 

That said, I don't think its been tested and so I would suggest someone seeks clarification from the relevant AUK official.

Of course, a scuba mask and a cycle might be possible, but I suspect completing the ride within time limits might be challenging.

Kiribati is on the international date line. It's quite small so you'll need a very meandering route to avoid loops.
Title: Re: Latest start to complete a 100km ride before midnight
Post by: JohnL on 22 December, 2017, 07:56:00 am
I’m too full of manflu to think this through sensibly(!) but what it you were at a pole? How would that work?

John
Title: Re: Latest start to complete a 100km ride before midnight
Post by: frankly frankie on 22 December, 2017, 04:44:58 pm
The event used to start it at 00:01 ...  Don't tell anyone, we actually set off at 00:00.

It was set up that way originally because various people including the then Events Sec and the then Brevet Cards Sec could argue round in circles for hours about which is correct, 24:00 or 00:00.
(And, before the same happens here, Wikipediea seems to think that either is acceptable - even quoting legal documents that support both usages.)
Title: Re: Latest start to complete a 100km ride before midnight
Post by: arabella on 22 December, 2017, 06:59:26 pm
Just a general guideline ...

If you are cycling from a point, and ending at the same point, (i.e. in a loop), the elevation gain will be the same as the elevation downhill. If there is headwind for half the way, there will be tailwind for the other half, so it balances out

depending on your fitness, you should finish a 100km ride in under 4 hrs (25 Km/hr) if you dont stop to rest for a lengthy period, and assuming you have no mechanical issues / punctures etc ...

obviously, if you are fitter, you will finish much sooner, but when I plan a new ride, I estimate the time based on 25 Km/hr .... if I finish sooner, it's a bonus
(my bold)
gosh, thanks, I hadn't realised I was unfit.  It's nothing to do with the world being designed for the average bloke or anything.
your new word for today is 'androcentric'
[possibly a bit unfair I am a tad cheesed off with various things at the moment]

and I don't understand the OPs question either.
Title: Re: Latest start to complete a 100km ride before midnight
Post by: Banjo on 24 December, 2017, 10:19:21 am
If it wasn't an Audax   there are riders who could do it starting at 2130 (1730 if it was me).
The 30km max speed for Audax makes the question pointless as plenty of strong riders can average faster.
Title: Re: Latest start to complete a 100km ride before midnight
Post by: Kim on 24 December, 2017, 10:50:04 am
For a standard 1% climbing 100km audax-style ride I'd assume about 20kph rolling average, plus faffing time (which can be almost nothing for 100km).  I might end up a little faster if the weather and traffic are good.

For touring pace I assume 10mph overall average, including food stops, mechanicals, stopping for photos, checking maps, etc, etc.  Over a long enough distance, it's freakisly accurate.

I've averaged significantly more than 20kph a handful of times.  All were on short rides, and with various degrees of cheating.

But then, I'm unfit.
Title: Re: Latest start to complete a 100km ride before midnight
Post by: mattc on 24 December, 2017, 03:28:33 pm
<snip>
depending on your fitness, you should finish a 100km ride in under 4 hrs (25 Km/hr)
...
<snip>
(my bold)
gosh, thanks, I hadn't realised I was unfit.  It's nothing to do with the world being designed for the average bloke or anything.
your new word for today is 'androcentric'
[possibly a bit unfair I am a tad cheesed off with various things at the moment]


I think it's a valid criticism - but please cheer up soon Ara, it's Christmas :)

I doubt dim meant anything, it's just lazy phrasing. The loaded "should". There are two general meanings of the word:
- you are obliged to do thing X. or
- I predict that you will do thing X.
Presumably in this context, the former cannot be the intention. SO dim is predicting that riders will do the thing he has described.

In which case I'd say he's made a huuuuge generalisation,. Does the writer know all his readers? Or all cyclists?

I'd say he clearly doesn't - there are millions of people on this planet who could not ride 100km in 4 hours. So what use is this statement?

And then of course there is the strong implication that you just aren't fit if you fall below this standard. You should train more (or smarter?), eat properly, etc. Get fit, you lazy so-and-so!

<ok, I'm probably a bit grumpy too ... I need to eat another cold pig-in-blanket ... nommm ... >
Title: Re: Latest start to complete a 100km ride before midnight
Post by: dim on 24 December, 2017, 05:18:26 pm
<snip>
depending on your fitness, you should finish a 100km ride in under 4 hrs (25 Km/hr)
...
<snip>
(my bold)
gosh, thanks, I hadn't realised I was unfit.  It's nothing to do with the world being designed for the average bloke or anything.
your new word for today is 'androcentric'
[possibly a bit unfair I am a tad cheesed off with various things at the moment]


I think it's a valid criticism - but please cheer up soon Ara, it's Christmas :)

I doubt dim meant anything, it's just lazy phrasing. The loaded "should". There are two general meanings of the word:
- you are obliged to do thing X. or
- I predict that you will do thing X.
Presumably in this context, the former cannot be the intention. SO dim is predicting that riders will do the thing he has described.

In which case I'd say he's made a huuuuge generalisation,. Does the writer know all his readers? Or all cyclists?

I'd say he clearly doesn't - there are millions of people on this planet who could not ride 100km in 4 hours. So what use is this statement?

And then of course there is the strong implication that you just aren't fit if you fall below this standard. You should train more (or smarter?), eat properly, etc. Get fit, you lazy so-and-so!

<ok, I'm probably a bit grumpy too ... I need to eat another cold pig-in-blanket ... nommm ... >

LOL ... I did not mean to offend anyone .... I was a bit baffled by the OP's question .... one should know how long it will take (approx) to ride 100km, based on your own fitness ...

I gave an example of 25km per hour based on the speed that I normally ride .... there are guys who I follow on Strava who average 30 Km/hr on rides over 135 Km long.

Title: Re: Latest start to complete a 100km ride before midnight
Post by: Exit Stage Left on 24 December, 2017, 08:37:44 pm
I just want to know what 'seriously JPO' means.