mr_pedro

My question is what is the best 2-man paceline strategy when one rider is stronger than the other?

In a large group it is key to have the entire line move at a steady pace. This reduces the harmonica effect of acceleration and breaking and keeps everything nice and smooth.

What I am wondering is, does this also hold for small groups? So e.g. if there are only 2 riders forming a paceline, the impact of the harmonica effect would be reduced and the fastest strategy could be one where the strongest rider also does faster pulls. Any thoughts?

Homebrew01

The stronger rider should do longer pulls, not faster. The speed or effort, should stay steady.

carpediemracing 

+1

With 2 riders a rule of thumb is that each rider should do about 30 second pulls, minimum, and closer to a minute, to give the other rider a chance to recover. You may want to reduce the length of the pull of the weaker rider to 15 seconds or so (20 revolutions?) and have the stronger rider do a minute or so. The key here is the recovery of the weaker rider - if the weaker rider can recover enough to pull at the agreed upon speed/effort then you're all good. If the weaker rider can't pull then the other rider needs to pull more. If the other rider needs to pull less because they're getting too fatigued then the two need to slow down.

When Greg Lemond led the Junior National Team to a bronze medal in the 70km Junior World Team Time Trial Championships he was by far the superior rider (Ron Kiefel, Greg Demegen, and one other rider was on the team). One rider crashed early on, leaving 3 riders (and the time is taken off the 3rd rider so the remaining riders had to finish). Another rider was unable to pull so sat at the back. One rider took about 30 second pulls. Lemond took 2-3 minute pulls and basically did the TTT by himself. I've never seen an article saying who crashed and who couldn't pull so I don't know that info. The TTT bronze against other countries' specialists, combined with his surprise silver on the track against a specialist (he'd raced on the track for something like 14 minutes in total before the Worlds), and the surprise gold (flat course, expected to be a big sprint, but he powered a two man break clear of the field to win the gold), marked him as a rider of the future.

bobones

Is it important for the riders to signal to each other the end of a turn, e.g. by guy in front flicking elbow or guy behind shouting "spell" or "spell up"? Seems to me that without communication, the guy behind is going to have to accelerate to get to the front and so disrupt the smooth flow and even pace. With communication the lead rider can ease off slightly to allow the drafter to come through at the same steady pace.

BTW, OP, I think you meant to say "concertina effect" as harmonicas don't move much!

valygrl

Is this intended for a team time trial type effort, where you are trying to go as fast as possible, or are you just out for a ride?

If the former - essentially I agree with cdr - longer pulls for the stronger rider, at a pace that allows the weaker rider to recover, and it depends on the relative strength difference what the pace & timing should be to maximize the speed. You'll need to do some practice to figure it out.

Otherwise - there's only two of you - why don't you just talk to each other?

bobones

Might be 2 of you in a break or (more likely in my case) having been spat out the back of a fast group, but still trying to keep the pace high and get back on. When you're putting in a threshold effort, talking is pretty difficult. I was in this position last Saturday: 2 of us alone were taking turns but not talking and I was having to accelerate to take a turn. We picked up a few other stragglers and went "through and off" which is just a rotating pace line where you don't really pull for any length of time at the front. In retrospect, when it was just the two of us, it may have been better if we signalled the end of a spell to avoid the accelerations.

evrythngsgngrn

fify.

Edit:

Oops, didn't see this before posting.

Looigi

"harmonica effect"

ROTFL. Sorry. I just cracked me up.

pdedes

That's just suck and blow. So 41

mr_pedro

It depends a bit on where your roots are for how you interpret harmonica:
https://en.wikipedia.org/wiki/Harmonika

Anyhow, for the best strategy it seems obvious that the person in front must go slow enough such that the person behind is able to rest and do a pull at a speed faster than the solo speed of the stronger rider. Doing a quick rotation of 30-60 seconds also seems to be preferable in order to be able to consistently pull at a significant level above FTP.

I just don't see a reason why for just 2 people the effort up front needs to be the same for both riders. When there is a large pace line, you want the people that are resting in the middle to be able to rest at a constant pace while they wait their turn. But when there are only 2 people the two riders are always switching between high and low power anyway and they can react much faster than when there is a large pace line.

I might be over-thinking this and maybe I just need to try it out. The other day I was trying to go around a 30 minute loop as fast as possible with a friend and I was 2 minutes faster than my friend. So we were wondering if we could improve my best time by staying together or if the difference between us two is too big for a pace line to work.

Bob Dopolina 

I've never heard 'spell' before. If you are going hard enough then the lead rider won't hear anything.

All that 'communication' is unnecessary. Everything that transpires should be non-verbal.

The lead riders simply needs to slide over a bike width into the wind with a flick off the fingers on the leeward side as they ease off slightly on the pedals. The following rider holds the same pace and the lead rider slips in behind as the other rider moves past him.

As for duration, with two riders switching every 30 seconds is far too quick as it isn't enough time to recover and you'd spend a huge percentage of time changing leads. I would pull for a minute or two and then switch off. That gives time for recovery and the amount of time spent side by side is a much smaller portion of the overall time.

FLvector

Although I do agree that the stronger rider should do longer pulls, the speed can vary if the weaker rider is able to recover and hang on while drafting. The weaker rider may only be able to pull at 20 mph and for a shorter time interval, then after moving behind the faster rider pulling at 21-22 mph, can easily maintain 22 without too much struggle. The stronger rider should pay close attention to be sure the weaker one doesn't get dropped and this should easily be communicated with only two people.

gregf83 

Consider the two riders to be a single entity. For the fastest time over a given distance you should aim for the same conditions as a single rider which is constant power for flat windless course. Any time spent riding above the average speed is less efficient.

If the weaker rider has an FTP less than ~70% of the stronger rider they should just sit in as they won't be helping. If you want to try this with a 400W pro, you'll need an FTP above 280W.

goose70

In addition to the other good advice here, nobody has mentioned race radios and a team car driven by a Directeur Sportif. Why would you attempt a two-person paceline without such support?

Bob Dopolina 

Race radios are how the organizer/officials communicate with the vehicles. Riders don't hear this. All races use these.

Rider radios are how the DS communicates with the riders. They are not allowed in some races. This is when the DS needs to scream at you over the PA or by hanging out of the car whilst banging on the outside of the door.

It really can be quite encouraging.

Nachoman

I guess it depends on how much stronger the one rider is.
If it's not a race type situation, it might be reasonable for the stronger cyclist the pull the entire time.

mr_pedro

I see that for a single rider, any energy spent above average power level is better spent to increase speed at times that power was below average. Because of non-linear relationship between speed and power this will increase the average speed.

Just wondering if this also holds for two riders.
So the if the faster rider pulls a bit slower, the slower rider is able to pull a bit faster as he will be more rested? But will this always produce a faster average speed?

bobones

Might just be a Scottish thing then. In a group riding two abreast, the second group shouts "spell up" to indicate that the lead pair should move over although the lead pair might move over anyway without anyone telling them to. Used if the lead pair has been on the front long enough or they are noticeably beginning to fade or riding too slowly for the bunch.

goose70

It's always a good day when a smartass comment results in me learning something new. Thanks!
Unfortunately, I do not race in events where support vehicles or radios come into the picture. At best, we get an announcer who lets everyone know who won the $5.00 carwash giftcard prime.

Smartassness aside and admitting that I’m also guilty of overthinking bike stuff, if any thread screamed “just ride your bike!,” it’s this one.

Bob Dopolina 

I thought it might be a regional thing.

big chainring 

Google the Trofeo Baracchi of 1962. Rudy Altig and Jacques Anquetil. Epic. "Courage Jacques, courage."
It's on Youtube, woo-whoo
https://www.youtube.com/watch?v=wQWN...Y&noredirect=1

And while you're at it "The Double" on Youtube.

Bob Dopolina 

A two up break is a personal thing.

mr_pedro

I know, but this is as much the numbers geek in me as the cyclist talking.

Anyhow, I did some calculations and the conclusion is that the stronger rider pulling slightly more than the weaker rider makes the paceline faster, but the differences with both pulling the same are negligible.

I assumed:
-No wind on a flat
-a certain improvement from drafting
-a certain quadratic relationship between power and speed
-some FTP for rider1 and for rider2
-instantaneous switches from pulling to drafting
-Normalized power for both riders is equal to their FTP

I was then able to solve for the pulling power of both riders that accomplishes all of the above and maximizes the speed improvement relative to the stronger rider riding solo. The results were that a maximum speed improvement is obtained when the stronger rider pulls a bit faster than the weaker rider pulls.
With the numbers I choose I was getting 285W for the stronger rider 62% of the time and 277W for the weaker rider 38% of the time.

However the differences between 285 and 277 are small and imposing a constraint that speed remains constant, I get 282W with a 67%-33% split. The difference in speed improvement between these approaches is very small (1.1km/h vs 1.07 km/h).

gregf83 

What FTPs were you assuming? How were you calculating NP?

wheelreason

Unless the difference in the riders is minimal, what will end up happening is one will pull and the other one will push.