Author Topic: Atlas Mountain Race.  (Read 2538 times)

Re: Atlas Mountain Race.
« Reply #25 on: February 17, 2020, 12:38:09 pm »
Last year, James H and Sofiane finished in joint first on Italy Divide. Sofiane appears to be significantly stronger now, or is it the terrain and conditions suiting his style / setup better?

James and Jay do indeed appear to be in a battle royale.

Re: Atlas Mountain Race.
« Reply #26 on: February 17, 2020, 12:51:46 pm »
Related, Im curios if there is much of an aero penalty with small fork mounted cages on a bike thats chugging along at 25kph for most of the journey.
I like to justify my aero components by pointing out the watts saved at any instant maybe lower but I am out there for far more hours at my pace.



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Re: Atlas Mountain Race.
« Reply #27 on: February 17, 2020, 01:32:57 pm »
Im curios if there is much of an aero penalty with small fork mounted cages on a bike thats chugging along at 25kph for most of the journey.

There is, for two reasons:
Firstly, bikes rarely chug along at a steady pace.  Nornally you go a good bit slower up hills and faster down them - and then you have disproproportionately more drag. 
Secondly, it's not your speed relative to the ground that dictates drag, but relative to the air.  If you go at 5 mph into a 20mph wind, then aerodynamics will make a big difference.  If you go at 20mph the other way, it won't matter at all!   
The rule is that slower riders save more minutes from aerodynamic improvements over a given distance than faster riders - because they are riding against the wind for longer. 

But: you have to put gear somewhere and anywhere you put it has some sort of aero penalty. Bags on the forks isn't great aeroz, but might just be the easiest and most handy place to put stuff.

bludger

  • Randonneur and bargain hunter
Re: Atlas Mountain Race.
« Reply #28 on: February 17, 2020, 01:38:24 pm »
I would really rather not put anything on the fork at all but when you're in that desperate a state....

What does mystify me a bit is that you never see frame-length top tube bags in these races. They lash onto the top tube, the seat post, and the stem. I appreciate that badly packed there might be a danger of thigh rub but I would really hate to have anything on the forks. Planet X used to do one (think it was branded as wilier), seems that it's gone when I look now.

YACF touring/audax bargain basement:
https://bit.ly/2Xg8pRD



Ban cars.

Re: Atlas Mountain Race.
« Reply #29 on: February 17, 2020, 01:46:23 pm »
If you combine one of those with a tail pack there’s nowhere to get your foot across to get on the bike.

(Unless you have a very low top tube like the bike pictured)

bludger

  • Randonneur and bargain hunter
Re: Atlas Mountain Race.
« Reply #30 on: February 17, 2020, 01:47:49 pm »
yeah but think of the gainz
YACF touring/audax bargain basement:
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Ban cars.

Re: Atlas Mountain Race.
« Reply #31 on: February 17, 2020, 03:18:28 pm »
Wouldn't work for me.  I have tried putting a bag there and it rubs.  My knees (especially right one) comes closest in at the top of the pedal stroke, so that is the worst place for me to put a bag. 

Some people do do it, but not many. 

What I've never seen anyone else do is put a bag under the down tube, behind the front wheel.  I did that successfully on a couple of events.  It gets dirty, but it's out of the wind.

bludger

  • Randonneur and bargain hunter
Re: Atlas Mountain Race.
« Reply #32 on: February 17, 2020, 03:28:46 pm »
Yeah it'd be OK for 'hopefully never use this' stuff i.e. pump, tubes.

How about inside the rear triangle? Where the traditional silca frame pump goes. Not a huge amount of room to be fair... Possibly enough for one or two other bits though. And it does free up room in other bags if you do put a pump there.

Other places which MTBers have used:

Inside the handlebars (which does actually work for tubeless plug kits).

Inside the top cap.

Inside the BB.

More of my bad ideas:

Inside a disc wheel.

On the other side of your SPDs

Inside the down tube / seat post (??)

Wedged inside a wheel

A thru axle that is also a toothbrush



YACF touring/audax bargain basement:
https://bit.ly/2Xg8pRD



Ban cars.

Re: Atlas Mountain Race.
« Reply #33 on: February 17, 2020, 04:27:28 pm »
There is a german company which makes a bag for the top of the rear triangle.  Expensive.  and only worth it on large frames

Re: Atlas Mountain Race.
« Reply #34 on: February 17, 2020, 05:42:31 pm »
Couple of people moving over from TT - Nick Clarke and Chris Hall.

Also Liam Yates, son of Sean.   Decent road racer trying a different discipline.
Also Rob Enslin, a former team-mate of mine at AW Cycles.

quixoticgeek

  • Mostly Harmless
Re: Atlas Mountain Race.
« Reply #35 on: February 17, 2020, 05:54:35 pm »

Is it Topeak or one of the other tool/pump makers who make a full set of emergency tools that you can store in places like a bar end, and even the hollow bottom bracket of a Hollowtech II crankset. I dunno if I would trust that to last the first Pavé segment tho...

I tried running 2 alpkit top tube bags on my top tube, but it didn't work, one does, the second doesn't.

J
--
Beer, bikes, and backpacking
http://b.42q.eu/

Re: Atlas Mountain Race.
« Reply #36 on: February 17, 2020, 06:28:46 pm »
Im curios if there is much of an aero penalty with small fork mounted cages on a bike thats chugging along at 25kph for most of the journey.

There is, for two reasons:
Firstly, bikes rarely chug along at a steady pace.  Nornally you go a good bit slower up hills and faster down them - and then you have disproproportionately more drag. 
Secondly, it's not your speed relative to the ground that dictates drag, but relative to the air.  If you go at 5 mph into a 20mph wind, then aerodynamics will make a big difference.  If you go at 20mph the other way, it won't matter at all!   
The rule is that slower riders save more minutes from aerodynamic improvements over a given distance than faster riders - because they are riding against the wind for longer. 

But: you have to put gear somewhere and anywhere you put it has some sort of aero penalty. Bags on the forks isn't great aeroz, but might just be the easiest and most handy place to put stuff.

Thanks Frank. I'm not totally getting on board with all of this though so please humour me.
I was under the impression that air resistance ramps up massively at higher speeds. (i.e.) its not a flat line graph. Wouldn't that then mean that aero is far more relevant as the speed increases? The shape of a sports car as opposed to a 2cv.  I do get that the slower rider is out in the wind longer, but does the fact that they are slower make it a different  strength of wind?
Also if a bike is loaded at the front/fork area. Isn't it just plonked in front of the rider and their rotating legs that is bad air anyway?
Lastly with regards to bags above the top tube, wouldn't weight distribution come into play in terms of rocking around and making the rider work to maintain balance? Heavy stuff down in the hold and all that.
often lost.

zigzag

  • unfuckwithable
Re: Atlas Mountain Race.
« Reply #37 on: February 17, 2020, 07:12:02 pm »
in aerodynamics speed with reference to the ground is irrelevant. what's important is speed in/through the air, so in case of a bicycle everything above the tyre contact patch. if the wind is head or cross-head it will play against your moving direction and for slower and non-aerodynamic riders it will be more significant. the reasons being 1) they are slower as they can't generate watts (due to fatigue, lack of fitness or both) 2) fighting wind speed requires higher percentage of all available power 3) due to lower speed more time is spent to cover the same distance.

mattc

  • n.b. have grown beard since photo taken
    • Didcot Audaxes
Re: Atlas Mountain Race.
« Reply #38 on: February 17, 2020, 07:42:05 pm »
Also if a bike is loaded at the front/fork area. Isn't it just plonked in front of the rider and their rotating legs that is bad air anyway?
I think there's definitely something in that. Also, front panniers [which must be similar to fork-leg-packs!] might be better than rear as you get a more "tadpole" shape. Which is generally better than a "reverse tadpole", IIRC



There was a MUCH DEBATED study of different pannier/bag locations in a windtunnel, probably in Bicycle Quarterly; I don't think it was very well done, but it did get people thinking a bit!
Has never ridden RAAM
---------
No.11  Because of the great host of those who dislike the least appearance of "swank " when they travel the roads and lanes. - From Kuklos' 39 Articles

bludger

  • Randonneur and bargain hunter
Re: Atlas Mountain Race.
« Reply #39 on: February 17, 2020, 08:02:14 pm »
I tried running 2 alpkit top tube bags on my top tube, but it didn't work, one does, the second doesn't.

J
interesting - I bet it could be made to work somehow but then really the reasonable thing to do would be to just have one big one.
YACF touring/audax bargain basement:
https://bit.ly/2Xg8pRD



Ban cars.

quixoticgeek

  • Mostly Harmless
Re: Atlas Mountain Race.
« Reply #40 on: February 17, 2020, 08:13:14 pm »
interesting - I bet it could be made to work somehow but then really the reasonable thing to do would be to just have one big one.


There are certain spacial requirements when coming off the saddle and straddling the bike that preclude the fitting of the second bag. On the plus side the experimentation was probably less painful for me than it would have been for a guy of the same inside leg length on that setup...

I have tried putting a spare tyre in that position, but it didn't really work that well either, tho it was just that bit lower so less of an issue. Mostly I couldn't get it to stay vertical. In the end was easier to just bungee said outer to the side of my front bag.

J

--
Beer, bikes, and backpacking
http://b.42q.eu/

Phil W

Re: Atlas Mountain Race.
« Reply #41 on: February 17, 2020, 09:42:21 pm »
Not a singlespeed in sight, at least from those who submitted their rig photos.

I'm not surprised 1x is proving more popular than 2x, seems to be the way things have moved in the recent past.

I've not found anywhere with commentary on the race so far. Be interesting to know how Christian Meier built his early lead. I'm also looking forward to seeing how Sofiane's strategy pans out on this race. Will he repeat what he did on Tour Divide and not sleep for the first 3 nights. James Hayden usually has a good whole race strategy, so I'm expecting he'll move up the order in time.

These guys are commenting on it.

https://www.dotwatcher.cc/race/atlas-mountain-race-2020

quixoticgeek

  • Mostly Harmless
Re: Atlas Mountain Race.
« Reply #42 on: February 17, 2020, 09:59:04 pm »

Has Sofaine stopped? Looks like James is reeling him in, Also looks like he's slowly edging out Jay, tho that one is hard to say.

J
--
Beer, bikes, and backpacking
http://b.42q.eu/

Re: Atlas Mountain Race.
« Reply #43 on: February 17, 2020, 10:08:49 pm »
Im curios if there is much of an aero penalty with small fork mounted cages on a bike thats chugging along at 25kph for most of the journey.

There is, for two reasons:
Firstly, bikes rarely chug along at a steady pace.  Nornally you go a good bit slower up hills and faster down them - and then you have disproproportionately more drag. 
Secondly, it's not your speed relative to the ground that dictates drag, but relative to the air.  If you go at 5 mph into a 20mph wind, then aerodynamics will make a big difference.  If you go at 20mph the other way, it won't matter at all!   
The rule is that slower riders save more minutes from aerodynamic improvements over a given distance than faster riders - because they are riding against the wind for longer. 

But: you have to put gear somewhere and anywhere you put it has some sort of aero penalty. Bags on the forks isn't great aeroz, but might just be the easiest and most handy place to put stuff.

Thanks Frank. I'm not totally getting on board with all of this though so please humour me.
I was under the impression that air resistance ramps up massively at higher speeds. (i.e.) its not a flat line graph. Wouldn't that then mean that aero is far more relevant as the speed increases? The shape of a sports car as opposed to a 2cv.  I do get that the slower rider is out in the wind longer, but does the fact that they are slower make it a different  strength of wind?
Also if a bike is loaded at the front/fork area. Isn't it just plonked in front of the rider and their rotating legs that is bad air anyway?
Lastly with regards to bags above the top tube, wouldn't weight distribution come into play in terms of rocking around and making the rider work to maintain balance? Heavy stuff down in the hold and all that.
Air resistance does ramp up massively with velocity (relative to the air as stated). The force is proportional to v squared, the work (the watts) to v cubed. Double the velocity and the work done against air resistance goes up by a factor of 8 which is huge. By being more aero you clearly save vastly more watts at the higher speeds. However, you don’t get much bang for your buck. The 40w you save may only give you an extra 1km/h. At much lower speed the same aero improvements may only save you only 10w, but the 10w may still buy you the same 1km/h and the same speed improvements buy you more time.


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Phil W

Re: Atlas Mountain Race.
« Reply #44 on: February 17, 2020, 10:32:54 pm »
Im curios if there is much of an aero penalty with small fork mounted cages on a bike thats chugging along at 25kph for most of the journey.

There is, for two reasons:
Firstly, bikes rarely chug along at a steady pace.  Nornally you go a good bit slower up hills and faster down them - and then you have disproproportionately more drag. 
Secondly, it's not your speed relative to the ground that dictates drag, but relative to the air.  If you go at 5 mph into a 20mph wind, then aerodynamics will make a big difference.  If you go at 20mph the other way, it won't matter at all!   
The rule is that slower riders save more minutes from aerodynamic improvements over a given distance than faster riders - because they are riding against the wind for longer. 

But: you have to put gear somewhere and anywhere you put it has some sort of aero penalty. Bags on the forks isn't great aeroz, but might just be the easiest and most handy place to put stuff.

Thanks Frank. I'm not totally getting on board with all of this though so please humour me.
I was under the impression that air resistance ramps up massively at higher speeds. (i.e.) its not a flat line graph. Wouldn't that then mean that aero is far more relevant as the speed increases? The shape of a sports car as opposed to a 2cv.  I do get that the slower rider is out in the wind longer, but does the fact that they are slower make it a different  strength of wind?
Also if a bike is loaded at the front/fork area. Isn't it just plonked in front of the rider and their rotating legs that is bad air anyway?
Lastly with regards to bags above the top tube, wouldn't weight distribution come into play in terms of rocking around and making the rider work to maintain balance? Heavy stuff down in the hold and all that.
Air resistance does ramp up massively with velocity (relative to the air as stated). The force is proportional to v squared, the work (the watts) to v cubed. Double the velocity and the work done against air resistance goes up by a factor of 8 which is huge. By being more aero you clearly save vastly more watts at the higher speeds. However, you don’t get much bang for your buck. The 40w you save may only give you an extra 1km/h. At much lower speed the same aero improvements may only save you only 10w, but the 10w may still buy you the same 1km/h and the same speed improvements buy you more time.


Sent from my iPad using Tapatalk

85% of the aero drag is the rider though.  Only so much you can get from the bike’s 15%  contribution.  A comparison was done between a road bike and low racer recumbent, same rider, at 20 mph.  The low racer position meant he was outputting 100 watts less to maintain the 20 mph. That’s with bog standard wheels.  All because of the rider being a hell of a lot more aero.

Now back to the racing...

LittleWheelsandBig

  • Whimsy Rider
Re: Atlas Mountain Race.
« Reply #45 on: February 17, 2020, 10:46:06 pm »
Back in the ‘80s there were aero panniers, front and rear, that supposedly were faster than standard panniers. Seems feasible that they might be faster than the random kegs strapped to the fork blades that current bikepacker fashion dictates.

Specialized Tailwind panniers
https://www.bikeforums.net/classic-vintage/1189185-road-test-bike-review-1982-specialized-sequoia-allez.html

There is a modern version of the Specialized panniers too.
http://www.bentrideronline.com/?p=7399
Wheel meet again, don't know where, don't know when...

quixoticgeek

  • Mostly Harmless
Re: Atlas Mountain Race.
« Reply #46 on: February 17, 2020, 10:46:21 pm »
85% of the aero drag is the rider though.  Only so much you can get from the bike’s 15%  contribution.  A comparison was done between a road bike and low racer recumbent, same rider, at 20 mph.  The low racer position meant he was outputting 100 watts less to maintain the 20 mph. That’s with bog standard wheels.  All because of the rider being a hell of a lot more aero.

That 85:15 is based on a normal road bike and rider. Attach enough junk to the bike and that 15% becomes more significant.

J
--
Beer, bikes, and backpacking
http://b.42q.eu/

Phil W

Re: Atlas Mountain Race.
« Reply #47 on: February 17, 2020, 10:47:19 pm »

Has Sofaine stopped? Looks like James is reeling him in, Also looks like he's slowly edging out Jay, tho that one is hard to say.

J

I don’t think he has. According to the race manual he’s on a section, with sections washed out, that requires some hike a bike

quixoticgeek

  • Mostly Harmless
Re: Atlas Mountain Race.
« Reply #48 on: February 17, 2020, 11:26:28 pm »
I don’t think he has. According to the race manual he’s on a section, with sections washed out, that requires some hike a bike

Yeah, Once I zoomed in a bit, I noticed he was very wiggly bit of terrain, so it looked like he wasn't moving.

Jay and James seem to be 14-20km apart, but it's really hard to tell if they are gaining, losing, between each other as the terrain could be a big factor. Wish we had time splits are more frequent locations.

I really should go to bed, but I can't stop watching the tracking.

J
--
Beer, bikes, and backpacking
http://b.42q.eu/

Re: Atlas Mountain Race.
« Reply #49 on: February 18, 2020, 07:35:17 am »
What I've never seen anyone else do is put a bag under the down tube, behind the front wheel.  I did that successfully on a couple of events.  It gets dirty, but it's out of the wind.

I've done/do that. When I need to return from the finish of a race by European train, I store the bag for my bike under the down tube, using Voile straps to keep it secure. I know, a slight weight penalty, but I prefer the peace of mind compared to not being sure I'll find something suitable to wrap the bike in.

These guys are commenting on it.

https://www.dotwatcher.cc/race/atlas-mountain-race-2020

Thanks Phil  :thumbsup:

Back to the current position, it looks like Sofiane had a couple of hours stopped last night. That's probably all he'll take, as I can see him finishing at the end of the day, depending upon terrain. A few ups but a lot of downhill to the finish.