what is your definition of "enough change"?

1 unit ;)

---

The entire event (IM) is like "death by 1000 cuts" and the best race is minimizing all those cuts and losing less blood than the other guy. - Dev

Two things:

1 - Was there a chance at all for pros to speak up about keeping the swim, in the pre-race meeting for example since it had been changed to 1 loop at that time? Or maybe the meeting was 2 days before? At IMMOO in 2010 we all sat in the meeting and they said the water is above the wetsuit limit for pros, but you'll be able to wear wetsuits anyway and there will be NO DISCUSSION. I was just wondering about IMMEL. I suspect that all too many pros were more than happy to not swim the full distance.

2 - Quarqs. I am riding an relatively old one that has been checked a couple of times. My zero offset is regularly -430, but will vary about 20 units depending on the temperature. Of course, that variation is usually because I take it from a warm house to a cool outside or a cool house to a blazing outside. If I seem to see a disconnect in the longer races with my PE and power (dangerous I know) then I'll backpedal. I know you manually calibrate, but do you ever backpedal on/during race day?

---

Brandon Marsh - Website | @BrandonMarshTX | RokaSports | 1stEndurance | ATC Bikeshop |

Brandon....why would there be no discussion if WTC was going to ignore its own rules? Who decides that there will be no discussion?

Guilty as charged

---

---

Save: $50 on Speed Hound Recovery Boots | $20 on Air Relax| $100 on Normatec| 15% on Most Absorbable Magnesium

Blogs: Best CHEAP Zwift / Bike Trainer Desk | Theragun G3 vs $140 Bivi Percussive Massager | Normatec Pulse 2.0 vs Normatec Pulse | Speed Hound vs Normatec | Air Relax vs Normatec | Q1 2018 Blood Test Results | | Why HED JET+ Is The BEST value wheelset

Jordan,

I typically see a change on the order of 1/32Nm per degree Fahrenheit temperature change. To put that in perspective, that's roughly 3 watts difference for every 10 degrees F. temperature change. It's not a big deal if temperatures only change 10 degrees but on a day like IMC a couple of years ago when you started with temps about 50F and ended the bike with them in the 90s it's suddenly becomes significant. I would add that those folks riding SRMs that aren't rejiggering their zero offset are generating less than excellent quality data any day the temperature varies a good deal over the course of the ride. This is really power meter use 101 territory.

How much shift are you seeing? Have you actually measured it?

YMMV,

Hugh

---

Genetics load the gun, lifestyle pulls the trigger.

Jordan, sounds like we agree that moderate-high surf/wind should not be reason enough to shorten or cancel the swim leg for the pros in an IM. Obviously each race venue is unique and there may be circumstances that force last minute decisions such as course manipulations or cancellations but IMO pro swims are being shortened or cancelled WAY too often and it seems to me like every time it happens we get an avalanche of tweets from people on site (generally the strong swimmers lol) such as "can't believe they cancelled the swim. Doesn't look dangerous at all." I think this is indicative of a trend amongst race organizers. They are being far too conservative and I think it hurts the pro athletes (or at least some of them) and negatively impacts the race from the athletes and spectators POV. To maintain a hint of relevance to the thread topic- IMMelb RD's decision to shorten the swim completely ruined Clayton Fettel's chances of winning, chances for exposure, and who knows how much money that was worth to him. It also made the spectacle less interesting to all of us enthusiastic viewers, because the pack formed early and there was no 'breakway' element to the race.

I agree that a "swim must go on" stance is silly, I may have come off a bit 'gun-ho' in my original comments. There are extreme temperatures in which swims must be cancelled. Especially hot water- I reckon that's more dangerous than cold. You're right that pros are not immune to hypothetmia but I'd like to see a different threshold for cancellations for AG vs Pro athletes. A given swim course might be dangerously cold for a 65 year old woman who will take 2 hours to cover the distance without warming up much, but that doesn't automatically mean it's too cold for a group of the fittest guys on the planet who are out of there in less than an hour- and RDs can count on them wearing appropriate gear + warming up appropriately. I haven't noticed a discrepancy between swim cancellations or alterations for AG waves and pro waves. It seems race organizers are content to cancel (or shorten) the swim for everybody, when it may only be dangerous for some. And the ones suffering are the ones who's livelihood depends on the event they've trained for.

The boundaries for "when do we call off the swim" -whether it's surf related OR temperature related- should be pushed a lot more than they are now (for the pros! AG is a different issue and I'm all for conservative decisons for the sake of safety). I think it's a good idea to establish an official surf/temp theshold (like the wetsuit legal/illegal rule)..one set of 'boundaries' for pros, one for AG. And I think if the established "cut off" temps/surf conditions are sensible, then there will be very few, if any, swim cancellations at IM events each year.

...which would be great, IMO.

Btw- congrats on another huge race! Great result

---

---

@EddyRoche
www.eddyroche.com

Related to this train of thought, the "cut off thresholds" for swim cancellations or shortening might also be different for <40, 40-59, and >60 age groupers.

I've never gotten more than 5 "units" change (aka 5/32Nm) and typically see 1-3 "units" over the course of a ride. This with temperature deltas as high as 20F. I'd struggle to think of a ride (or race) I've done with more swing than that. I live in pretty temperature stable areas.

That said, even 6w is "only" 2% or less at race pace for me, so perhaps less of a concern for me than someone who is racing with a target power in the high 100s.

I do check it regularly, but I also use the Garmin 500 temperature for reference and don't know how accurate that really is either.

Thanks for the feedback. It's surprising.

I will do some recording this month and report back. Though I do have the newer spider, which of course is still more refined in all areas.

---

"Non est ad astra mollis e terris via." - Seneca | rappstar.com | FB - Rappstar Racing | IG - @jordanrapp

That's an interesting suggestion Dev but I think it's too much risk, too little reward.

Age really is just a number nowadays. There are guys/girls in every AG that will swim like fish, and likewise there are athletes in each AG that will swim extremely slow. Age isn't necessarily an indicator of physical ability or general conditioning.

With the pros, RDs can count on each athlete being adequately prep'd and they can monitor them during the swim due to low numbers in the water and inevitable pack-forming.

It would get a bit messy having one AG doing a half swim on a last-minute modified course such as IMMelb but other AGs doing the full originally planned swim course.

When it comes to AG athletes and IM, I understand RD's inclination to make decisions to keep everyone safe, even if it means subtracting from their overall experience. But to go back to what I said earlier, I don't think these decisions should be impacting the pro race the way they are.

---

---

@EddyRoche
www.eddyroche.com

At pro meet on Saturday (day before race), swim course change to two 1.9km loops to concentrate water safety personnel and to avoid the more exposed north side of pier was announced. That was obviously fine with all of us. Different course of 3.8km made sense because two loops meant less area for lifeguards to watch.

The change to 1300m swim was made on race morning, so no chance for discussion. It didn't seem likely on Saturday that such an option would be needed. But winds did increase substantially over night.

Biggest issue was that because these decisions were all being made on race morning, time was ticking away. If pros were to do full 3.8, we needed to go off at scheduled time. It would not have been feasible or reasonable to delay the AG athletes another hour while we swam. But it also would have been terrible to have us all start as we did but the. We swim 3.8 and have to ride through the whole AG field.

So given the options, I think what happened was the best decision. Only way to have done better would have been to have a greater number of contingencies lined up in advance. And even then, it still might not have been feasible in such a short time frame. You came male these decisions until the sun comes up because you can't really evaluate.

So I'm definitely not criticizing the RD for the decisions on the day. Best case is just to have more plans to have pros swim full 3.8 in advance.

---

"Non est ad astra mollis e terris via." - Seneca | rappstar.com | FB - Rappstar Racing | IG - @jordanrapp

Yep, sounds like it was so last minute that there was little other choice in this case.

I think a lot of age-groupers were caught off guard, even only spending half an hour in the water. A shortened swim for them was a great call. My dad was watching and said he saw a few people brought in on skis, some of them after only a minute or two. He found one guy of around 40yrs old on the beach afterwards, still in his wetty, crying. He couldn't get past the shore break, apparently.

Anyway, Jordan, you sound like a top bloke. Well done out there.

For differentials, probably OK...for absolutes, not so much. Mine always seems about 10F too high.

---

http://bikeblather.blogspot.com/

Well stated.

Mieke
Quarq Technology

Glad I'm not the only one...

---

"Non est ad astra mollis e terris via." - Seneca | rappstar.com | FB - Rappstar Racing | IG - @jordanrapp

---

I saw this on a white board in a window box at my daughters middle school...
List of what life owes you:
1. __________
2. __________
3. __________

Actually in the shade they seem to read right on. It's when they are sitting in the sun that they read high. In Puerto Rico and Hawaii I've seen them read 20 degrees high while just sitting still. Moving along the airstream allow them to shed a bit of the extra solar gain. Just think about how hot the surface of a parked car gets while sitting in the sun.

YMMV,

Hugh

---

Genetics load the gun, lifestyle pulls the trigger.

Certainly. Interestingly, on my TT bike, it tends to be more accurate, I *think* because it's in the shade of my body. On my road bike, where it's out in front of the bars, that's where it tends to read high. I figured it was just the effect of being in the sun, but I also thought Garmin might have realized that was going to happen and take some steps to account for it.

---

"Non est ad astra mollis e terris via." - Seneca | rappstar.com | FB - Rappstar Racing | IG - @jordanrapp

Sounds like you have more faith in the Garmin guys thinking of stuff like that than their recent track record has indicated... :-\

---

http://bikeblather.blogspot.com/

Moving along the airstream allow them to shed a bit of the extra solar gain

Unless you drip sweat on it I'm with Rapp, Its the shade that is cooling it not airflow.

---

Styrrell

I would think that the temp of the strain gauges inside the Quarq would be only be affected by the temp of the ambiant airflow. It's not like being in the shade or sun would make any difference as the object does not have time to heat up due to sun exposure, because it is "cooled" to the temp of ambiant airflow. We have the same affect in base stations that need to go up on a post in Saudi Arabia or Dubai....if we can assure enough ambiant airflow, it won't overcook from sun exposure, even though the ambiant airflow may be 45 C.

Shade is certainly important but so is air flow if the unit has a higher temperature than the ambient temp., Convective heat loss increases a good deal with increased air flow.


Hugh

---

Genetics load the gun, lifestyle pulls the trigger.

It sounds as if you don't "believe" in convective heat transfer :-/

---

http://bikeblather.blogspot.com/

---

Styrrell

Obviously you don't understand convection very well.

---

Genetics load the gun, lifestyle pulls the trigger.

Right...and we are discussing that the Garmin 500 temp readings are typically 10F or more ABOVE the ambient temps.

---

http://bikeblather.blogspot.com/