Legal Drafting on the Bike
I've driven a motorcycle with a race official on the back at an Ironman about 6 times. I was also a official on the back of Harley driven by a guy who couldn't ride for shit in the rain at IMLP '08 (or '09, can't recal). But basically, I was another official out there/set of eyes, helping the official spot bike rules violations.
It's been about 2yrs though so someone please correct me on the 4 bikes/20" stuff below, but the rest is accurate:
The rules are:
- You have to maintain 4 bike lengths between you and the bike in front of you (their rear wheel to your front wheel = 4 bike lengths).
- Once you get inside this 4 lengths, you have to pass. You have 20secs to complete that pass.
- The pass is completed when your front wheel breaks the plane of their front wheel.
- At that time it is their responsibility to move out of this draft box, dropping back to this 4 bike lengths. They have 20secs to make that happen.
The net:
- Always ride 4-5 bike lengths off the bike in front of you. There is definitely a watts savings when doing this and it's legal. The savings is especially great when the guy you're behind is behind another guy, who's behind another guy, etc. IOW, you're last in a line of many people. Who cares what they are/are not doing/are they riding legal, etc. That's for the official to decide or fix. Just stay 4-5 lengths off the bike in front of you.
- Take your time/soft pedal when passing people, working your way up to their wheel inside this 4-bike box. Remember, you have 20" to complete the pass. That's potentially 20" to come off the gas 10-20% and still execute the pass.
- When being passed, take as much of your full 20" to back out of the box, especially if the person passing you passes you and then moves over the right, directly in front of you = a 20" opportunity to come off the gas 10-20%.
Finally, there is one common situation that the rules don't really address:
- Billy and I are riding the same speed, I'm 4 bikes off his back wheel.
- Billy moves over to the left to pass you, quickly also putting me inside your 4-bike box so I move over to the left also. The rules discuss what you and Billy are supposed to do in relation to each other but they don't talk about what my responsibilities are in relation to Billy. I can't pass him while he's passing you...though I suppose I could as long as I don't go over the centerline.
- In a situation like this, and in fact in pretty much all situations like this on the bike, the marshalls are looking for intent. All of the marshals are (or at least should be) experienced cyclists. You KNOW, through body language, bike positioning, etc when someone is trying to intentionally draft vs not pay attention, etc. The marshals are looking for the former peeps first, the latter second. In my situation above, after I've passed you (remember, you've also just been passed by Billy), I would either:
- Pass Billy, so there was no mistaking my intention: I passed you, now I'm passing Billy, done. Or...
- I would very quickly get my 4-5+ bike lengths distance behind Billy. Coast, sit up, whatever, to display my intention to get back to very legal as quickly a possible.
All of this just smart riding. It's working within the rules, and being legal at all times, to save energy. This is especially powerful for slow swimmers/strong bikers (Tom Glynn) who can effectively ride from legal draft to legal draft as they pass hundreds of people. IMO, just not smart racing to legally use this situation to your advantage.
Now...this post does not replace the rules briefing at the race. Please attend/talk to someone who did, to get the skinny on the bike lengths and seconds to pass jazz above.
Comments
Thanks to Rich for posting this timely note. It's spot on about the rules and how you can leverage them to your advantage. With over 2500 peeps on the bike course, there are plenty of places to pass / be passed and every single exchange like that is a chance to conserve watts. Most folks approach passing as a "I must hammer to make this happen" exercise when really that's the opposite of what you should be doing.
If you are riding your Steady watts and are about to enter the 4 bike length zone, you should continue know that you can ride "steady minus 10% of your watts" right up to their wheel and then pass quickly, ideally back at your steady watts.
If you want to pass someone but think that it might take you a couple of extra watts to make it happen, then drop back to legal and set it on cruise control. The only time I push that pass is just before an aid station if I want to be 100% safe by putting myself first. Otherwise it's your duty to ride as cheesily as possible.
On three loop courses, like IM Arizona, for example, almost everyone has the chance to take advantage of this experience.
Man, we have found a lot of free speed this year!!!!
Here are the WTC rules, which are different from USAT. WTC allows you to drop back for 20 secs, but USAT says you must do it immediately.
http://ironmanwisconsin.com/course/rules-and-regulations/
One note: once you enter that 4-bike box, you MUST pass. That is, you can't get up to within a foot of their wheel, change your mind, drop back to 4-lengths, change your mind again, try again, change your mind...etc. Otherwise you could just do this all day
.
Now, of course the person you're passing could accellerate, making you earn it, now your dragracing him...but that never happens.
Remember: at the end of the day it comes to down to >2800 athletes and about 15 officials. They are looking for intent first, rule violations second. In the situation above, I would totally sit up and drop wayyyyy back, farther than the 4-bike box, then go back to riding my race, NOT passing the guy.
Finally, don't get all worked up by what you see or what you think you see. I can tell you that when you're on a motorcycle riding just behind a group of riders with time to see situations develop, with an offset perspective (vs right behind everyone) with which to actually see the distances between the riders, it usually isn't as bad as it appears to be from your perspective: a group of riders riding very closely together. On the moto you'll see passes developing and being made, what looked like 2 bike lengths from behind was, in fact, 4-5 now that you're behind and to the left of them, etc. As a driver I would pass all the oneseys and twoseys, see a group up ahead and gun it to catch them. Pull in the clutch and coast quietly, watching. More often than not what I would see is a rider who's worked, not paying attention, looks up to see they are 3 bike lengths off but is too tired/doesn't care about passing and just drops back. That's fine, see intent.
But you immediately pick up on the ones who are softpedaling to stay within 2-4 bike lengths, not passing. Or who are riding 2-3 bike lengths off but offset to the left (doesn't matter, there is no "offset," it's a foul). I'll watch them, even flip the bike around and hide behind a bush to come up on them again, etc.
Fun stuff!
Jennifer, do you have wiki priviledges? If yes, you could make a Free Speed on the Bike wiki post. Introduce the concept then link to the various threads we have on the topic: fit, bottle/computer setup, tire selection, this thread on using the rules to your advantage, etc. PnI can then a link to your page to the wiki Table of Contents page.
The question in my head is "How do I handle these so called packs that are going to be buzzing by?"
After reading the tips above, I suppose that I will use the legal drafting techniques, keeping an eye on my PM, and then just let the wheel ahead go on if I have to press too hard to maintain 4 bike lengths. Right?
I really don't expect to be passing too many pacelines so I'm not going to give too much energy to figuring out how to handle that one....If I'm racing in my box, using an FTP of 250-260watts and I'm passing a paceline, then that's a slow group of riders.
At IMFL those packs will develop and pass you, especially at your FTP pace. My experience there is to let it happen, drop back to the back of the pack, get legal and enjoy the ride. I sit up, stretch, eat, do whatever admin I can while maintaining just a wee bit more than my original speed. This will all fall apart when you get to the "hilly" back section as all those knuckleheads will be hammering up the hills while you sit on your watts, then re-pass them as you maintain your steady wattage pace downhill. Don't worry as all those guys (and it's always guys) will be gassed by mile 95 as you pedal steadily off the front, slingshotting everyone of them as you go past. Have fun!
P.S. I went 5:37 at IMFL on 147 average watts from an FTP of 230; with decent aero you should be able to do much better. And yes, I ran well afterward.
I'm assuming that if I were to consider grabbing the last wheel (legally, 4 bike lengths stuff), the bump up in efforts (watts) just to find the sweet spot of holding 4 bike lengths would be too cumulative and costly by the end of the day.
Basically, squashing any hopes of a good VI.
But here's the thing: you won't have to up your power output to keep up as the draft will be worth at least 23-30 watts. Sit in! Enjoy the legal ride!
I've added a bamboo stick that's exactly 4 bike lengths long onto my aerobars. I should be safe.
However....it's 4 of Avery's bike lengths...and she's only 8 year's old!
Somantics.