Drafting - How much quicker?

Bullet1

I generally ride solo or with a mate who is a fair bit slower than me so have never really maximised the benefit from drafting.

This weekend however i'm taking part in a sort of 40 mile team time trial with some colleagues against some other local businesses.

When riding solo on a predominantly flat course over 30 miles I'll average roughly 17 mph, so, assuming I'm the slowest in the group, working in a team of 5 or 6 what sort of average speed do you whink is achievable?

markhewitt1978

I think the main benefit you'll find is the ability to save your energy for longer, rather than an a specific increase in maximum speed.

JayKosta

My guess...
If all the riders are '17 mph solo', AND they can work well together as a team, then a team speed of about 20 mph.

With a 'mixed speed' team, it depends on how fast the slowest rider can hang-on (even without doing any time at the front).

Being a member of a team entails a lot of responsibility - maintaining effective and safe distance, and when at the front being extremely aware of road surface problems and making adjustments well in advance so the team can safely follow.

Jay Kosta
Endwell NY USA

smidsy

You will only go as fast as the person on the front so the end result will be what ever the combined sustainable average is.

Another way of answering the question is that it is generally accepted that you benefit about 20% efficiency by drafting.

iPete

https://vimeo.com/70921986

ianbar

i have limited experience drafting too but what i have found is i can hold my higher speeds easier, if i was riding with someone a bit faster i do think my speed would be dragged up. when i rose a sportive the other week i caught a group of about 15, and sat on the back....it was fab! i was hardly peddling but doing 16-17mph. i think you could up your average alot in a team if you all know what your doing.

MickTheMove

It's great fun drafting along behind a little pack but if they are all faster than you normally, you will still have to work hard to stay on the tail, and when it's your go at the front you end up bulldozing along for fear of slowing everyone down thus having to work 20% harder! :oops:

Emphursis

A lot.

I honestly didn't think there would be much benefit, but in the sportive I did a couple of weeks ago, I stuck with a large group for the first two hours, and was averaging 18mph comfortably (as it, able to talk, not feeling out of breath or tired) whereas the closest I have got to that speed on my own is 16.9mph for an hour, and I was absolutely knackered afterwards.

markhewitt1978

It's really hard to judge pace. I was cycling with a group on a sportive at the weekend, and I was able to stay behind them easily enough and went for a turn at the front, but I either kept getting too far ahead or slowed down too much.

JayKosta

When you take your turn at the front, just work to maintain the group speed - don't accelerate. And don't stay at the front too long or else you might drop off the rear.

Jay Kosta
Endwell NY USA

oldwelshman

Experienced riders will save 20 to 30% drafting but inexperienced riders maybe 5 to 15% as it is also about being able to ride close to wheels and in right position depending on the wind conditions and direction. I have ridden in many events, even races where riders have no clue how to draft most efficiently and choosing wrong side to draft on with cross winds.
Overall if you ride correctly should gain minimum of couple mph as a group.

awavey

might there be some tendency in even small groups (and Id accept its down to inexperience and misjudging peoples ability) to up the pace regardless anyway because thats whats assumed or expected you just do.

its just the only times Ive tried drafting myself, or led for someone I trusted hanging on my bike wheel for a bit, we absolutely thrashed ourselves over the route we took,setting a far quicker pace than we actually needed to, burned off any energy gains we were making by drafting, finished the ride and everyones sort of looking at each other stoically recovering and sort of giving that why were we going so fast as we all could barely hang on to each other look, and the only reason people come up with is well I thought thats how we had to do it because we were drafting and its "quicker" and I thought youd want to be going faster...

slowbike

awavey wrote:

its just the only times Ive tried drafting myself,

That's an amazing feat - I'd like to see that ... do you end up going round in circles though?!

smidsy

awavey wrote:

finished the ride and everyones sort of looking at each other stoically recovering and sort of giving that why were we going so fast as we all could barely hang on to each other look, and the only reason people come up with is well I thought thats how we had to do it because we were drafting and its "quicker" and I thought youd want to be going faster...

What you describe there is peer pressure not the effects of drafting

Runtothehills

oldwelshman wrote:

Experienced riders will save 20 to 30% drafting but inexperienced riders maybe 5 to 15% as it is also about being able to ride close to wheels and in right position depending on the wind conditions and direction. I have ridden in many events, even races where riders have no clue how to draft most efficiently and choosing wrong side to draft on with cross winds.
Overall if you ride correctly should gain minimum of couple mph as a group.

This sounds about right. I can normally maintain about 21-22 mph for an hour on my road bike but when I did an event with someone else who could average about 20 we did roughly an 23.5 mph average for a 25 mile time trial.

However will you practice as a group beforehand and how far do you trust the others in your team? I trusted the other guy enough to leave about 5cm between us (I normally couldn't see the back of his back tyre because of my front wheel) but I'd never do that with someone I didn't trust. We hadn;t riden much together beforehand though.

The other thing I'd recommend is to discuss how you'll do the changeovers and what length pulls you'll be doing on the front-and talk during the event so you know how everyone is feeling and who needs to take longer/shorter pulls or if the group needs to speed up/slow down.

roger_merriman

The answer would seem quite a bit, see http://www.cyclingweekly.co.uk/news/latest/539809/ridelondon-riders-smash-up-surrey-strava-segments.html also the closed roads i'm sure helped.

Bullet1

Most of us are fairly experienced rider (4,000 miles a year plus) but given work & family commitments etc dont tend to get out in groups too often.

By the sound of things the 17mph could be converted to 19/20mph.

We were talking of 2 minutes / 1km stretches at the front before the lead man pulls off to the right (minding traffic)and the team 'undertake' him.

Runtothehills

Bullet1 wrote:

Most of us are fairly experienced rider (4,000 miles a year plus) but given work & family commitments etc dont tend to get out in groups too often.

By the sound of things the 17mph could be converted to 19/20mph.

We were talking of 2 minutes / 1km stretches at the front before the lead man pulls off to the right (minding traffic)and the team 'undertake' him.

Sounds about right speed wise assuming you're of equal fitness. Getting out in groups isn't essential, I do nearly all of my riding solo, but it is key to trust the others not to do anything unexpected like break sharply without warning (beware of corners and junctions, think about increasing your spacing as you approach and don't accelerate hard out of them as you'll fracture the group) or change direction.

In terms of length of time on the front that might be a bit long, I'd suggest a minute or so to start with but if some members are stronger they should do longer not faster turns.

When I did the 2-up time trial my partner and I were on normal road bikes with normal gear but managed to beat some people that were probably fitter than us and had clip on aero bars and time trial helmets simply through being good at riding together. We saw a few pairs than had obviously being doing equal turns for the first half and were then riding 5 m apart with the stronger riding yo-yoing away from the weaker and never giving them a chance to get into the slipstream. By sticking together and communicating honestly we probably gained 2-3 min over 25 miles.

Nickoo

you save 33% of your energy from drafting

pilot_pete

That's very precise nikoo....which study provided the figure?

PP

Runtothehills

33% is approximately 1/3 so I'm guessing it comes from a rough and ready estimate. The actual percentage reduction depends upon if you're the 2nd, 3rd or whatever rider in the line, type of bikes and gear, speed, if there is a head/tail/cross wind, road surface, gradients.

Also the percentage isn't that useful anyway as let's say drafting give you a 33% reduction - what does that do to you're average speed going from a solo to group ride which is what Bullet1 wanted? As you're going from steady state effort to intervals and probably don't know everyone's power output anyway and may spend variable amounts of time in the wind what does it mean in speed terms? The only thing you might be able to do with it is say that anyone that can't go at 87% of your speed normally won't be able to keep up even by drafting you (87% of speed give roughly 66% of power output).

socistep

I got mildly irritated by someone drafting me up a hill a couple of weeks ago, its this one here and regular commute route

http://www.strava.com/segments/771788

I was tired and was taking it steady, am 4th on there and was a fair way off that but this bloke followed me up right behind me. I've actually seen him a few weeks before where I'd gone passed him on the bottom just taking it steady, he then came sprinting passed and died a death so again just chugged past him, there is another uphill just past that segment and he tried it again and the same thing happened! That amused me though, some strange people around!

smidsy

socistep - not entirley sure how your post has added to the OP's uestion.

It does however tick the 'look at me I'm 4th' box :-)

socistep

smidsy wrote:

socistep - not entirley sure how your post has added to the OP's uestion.

It does however tick the 'look at me I'm 4th' box :-)

Yeah I know what you mean, I looked at your post here and had no idea how it related to the original question

viewtopic.php?f=40004&t=12935456&p=18479053#p18479053

It does however tick the 'look at me I've cycled abroad' box :-)

Monty Dog

Your average is likely to be dictated by the powers of recovery of the slowest rider, or simply their ability to hang-on. A common mistake is for the lead rider to pull-through too hard making it really hard for the recovering riders to get back on. The aim is to keep the pace as consistently high as possible rather than each rider taking it in turns to tear the legs of the others - in which case you might want to vary the length of pull depending who are the stronger riders, and the weakest only taking short pulls.

smidsy

socistep wrote:

Yeah I know what you mean, I looked at your post here and had no idea how it related to the original question

viewtopic.php?f=40004&t=12935456&p=18479053#p18479053

It does however tick the 'look at me I've cycled abroad' box :-)

Suggest you read it again - no where do I claim to have ridden abroad.

teisetrotter

I had an education on the Ride London. First 40 miles we averaged 41kph in a huge peleton train. On my chain gang for the fast middle part we average 33kph with some undulating hills, on a fast Saturday ride we average 29kph and on a solo hillyish ride i'll average 27kph. Went on holiday to Suffolk with not a hill in sight and I averaged 30kph over 70km on my own giving it everything.

Lots of factors there.

But the Ride London proved on a flat area with no wind to worry about the pace could be startling ......... and no red lights of course.

Conclusion 10 -15% difference.

awavey

smidsy wrote:

awavey wrote:

finished the ride and everyones sort of looking at each other stoically recovering and sort of giving that why were we going so fast as we all could barely hang on to each other look, and the only reason people come up with is well I thought thats how we had to do it because we were drafting and its "quicker" and I thought youd want to be going faster...

What you describe there is peer pressure not the effects of drafting

well yes I know that but thats what Im saying isnt there a tendency in an inexperienced group for that peer pressure to lead people to push far harder and over extend themselves, so when everyones uploading the ride to Strava going wow draftings cool its soo much quicker!!!. it just becomes one of those things everyone accepts drafting is just quicker, without understanding actually what we were doing to achieve that or where the real benefit was coming from, we were quicker because we were pushing alot harder than we'd normally have done, not just because we were drafting.

so having a chat pre-ride about the pace your going to be attempting and setting, might be a suggestion worth keeping in mind, just to make sure everyones got the same understanding

pilot_pete

I posted this on a thread about group riding etiquette recently, but it may add something to this subject as well for those who have not drafted before. It is a guide I put together for our club winter chain gangs...

http://congletoncyclingclub.org.uk/docu ... anging.pdf

PP

oldwelshman

Bullet1 wrote:

Most of us are fairly experienced rider (4,000 miles a year plus) but given work & family commitments etc dont tend to get out in groups too often.

By the sound of things the 17mph could be converted to 19/20mph.

We were talking of 2 minutes / 1km stretches at the front before the lead man pulls off to the right (minding traffic)and the team 'undertake' him.

Riding lots of miles does not really equate to an experienced rider, especially in groups :-)
There is more than one way to draft. The scenario you describe above is not the most efficient as it is one line and 1km pull is too far so this would be moderate pace.
If you ride in two lines and front rider moves once past front rider (left or right depending on wind direction) you will go faster and save more energy.
To the rider who said they just got tired, that's because you were judging effort poorly and you need to practice. The passing line does not accelerate through when your on the front, this just opens the gap behind you and rider looses drafting efficiency and has to ride harder to close gap and you end up working hard with less gain.
The passing line of riders ride smoothly just slightly fater than the slower line so you all remain close together and take about 4 or 5 second to pass the front rider before moving in, not accelerate hard as you can once your on the fron so what you should see is two lines of riders close to riders in front, one line slightly faster than other, this is called "through and off"

Daz555

Nickoo wrote:

you save 33% of your energy from drafting

Depends how fast you are going.