I am preparing for IMWI and they have some rolling hills and with the new route have added a pretty steep climb. 15-20% grade. I keep hearing commments about IMWI being too hilly for a disc and that the new hill makes using a disc a bad idea. I used my disc in 2014 and it was fine. I do understand the potential for weight savings with a light wheelset over a heavy disc, but even if that was the case, is 200-300 g really that big of an issue? I have an older HED jet disc that I use for all racing but I have an older FLO90 as well. They really weight about the same (1200 g or so) at least according to online data.
I was going to use disc on race day and everyone’s eyes keep bugging out when I tell them. It seems that no one I know is planning on using a disc on this course, and if they were, they have changed their mind given the course change. I have no idea why they feel this way. In my case the disc and the flo90 weight about the same, same tires, same cassette. I have heard a few people say “only really strong riders should use a disc on this course”. What does that mean?
it means you are foolish to not use a disk if you have one on that course. but people are easily scared by talk. there is nothing different than 2014. does one time up a 4-5min climb really negate a disk and give advantage to a light wheel, which your flo is not? answer…NO
The issue with a disc is that people don’t “feel” the extra speed they are getting over most of the course, but “feel” the extra weight they are struggling with on the hill (especially at low cadence). This causes them to think that the disc is a bad idea, when it is demonstrably faster. Seriously, what % of the time spent on the bike is going to be on that 15-20% grade (answer <<1%).
Bottom line: light wheels feel faster, aero wheels are faster.
People also have this misconception that aero gear only starts to help you beyond a certain speed (which is also demonstrably BS); that’s where the “strong rider” idea comes from.
You would have to be climbing Alpe d’Huez to be worse off on the disc, and even then its a matter of a few seconds.
I think the important thing for those climbs would be to have a power plan and STICK to it. Crawl up the hills if you have to in order to maintain your power targets.
I have used my disc/808 in all my races for like the last 10 years. Does not matter how hilly the course was. I sure got lots of strange looks
and comments, but, I just tell them these are the only racing wheels I have. Worked okay for IMLT with the killer hills. Or Donner. Or Auburn. Etc.
15-20% grade? Says who? Nobody is getting up that with anything less than, say 39/26 gearing at a minimum. Unless there’s only a 20yd stretch that is that steep.
Alpe d’Huez is like 8%, for comparison, with the steepest bits around 14%.
Use the disc. The new course on BBS is 3-4 minutes FASTER. There is more flat, less hills which adds more validity.
100% ride the disc, it will be faster. Unless you don’t know how to change a flat
I am preparing for IMWI and they have some rolling hills and with the new route have added a pretty steep climb. 15-20% grade. I keep hearing commments about IMWI being too hilly for a disc and that the new hill makes using a disc a bad idea. I used my disc in 2014 and it was fine. I do understand the potential for weight savings with a light wheelset over a heavy disc, but even if that was the case, is 200-300 g really that big of an issue? I have an older HED jet disc that I use for all racing but I have an older FLO90 as well. They really weight about the same (1200 g or so) at least according to online data.
I was going to use disc on race day and everyone’s eyes keep bugging out when I tell them. It seems that no one I know is planning on using a disc on this course, and if they were, they have changed their mind given the course change. I have no idea why they feel this way. In my case the disc and the flo90 weight about the same, same tires, same cassette. I have heard a few people say “only really strong riders should use a disc on this course”. What does that mean?
If you have a disc, you will almost always do better on it, as long as you can handle the cross-winds.
I just need to point out that discs make bikes MORE stable in crosswinds…not less stable. This is another pervasive untruth that leads people to believe discs are somehow more difficult to “handle”. The front wheel depth is what you need to be concerned about in a crosswind. But, with a disc, the deeper you can go in the front and retain stability.
Unless the winds are monster…like 50mph+ and it picks you up and throws you off the road (which does happen), a disc will add stability to the bike.
The funniest thing I see are folks “scared” to run a disc from a handling perspective and then they run 808’s front and rear. Symmetrical wheels are the MOST UNSTABLE setup you can run…well, besides a disc up front and a shallow wheel in the rear but obviously no one does that…You always want to be deeper in the rear as a minimum. Disc always preferably.
That’s what I meant to say. You are right, the disc does stabilize, it’s just the bike handling skills. I see some people just get nervous and pull out of aero in cross winds.
The issue with a disc is that people don’t “feel” the extra speed they are getting over most of the course, but “feel” the extra weight they are struggling with on the hill (especially at low cadence). This causes them to think that the disc is a bad idea, when it is demonstrably faster. Seriously, what % of the time spent on the bike is going to be on that 15-20% grade (answer <<1%).
Bottom line: light wheels feel faster, aero wheels are faster.
People also have this misconception that aero gear only starts to help you beyond a certain speed (which is also demonstrably BS); that’s where the “strong rider” idea comes from.
I really like your use of quotes around “feel”. It reminded me of a thread from several years ago where someone said they could feel the difference between their 900 gm rear wheel and the 970 gm disc.
That said, I do wonder about how laterally strong a disc is with regard to tight switchbacks descending at speed.
15-20% grade? Says who? Nobody is getting up that with anything less than, say 39/26 gearing at a minimum. Unless there’s only a 20yd stretch that is that steep.
Alpe d’Huez is like 8%, for comparison, with the steepest bits around 14%.
The entire climb isn’t that steep, but the third “kicker” is pretty damn steep (and kinda long) and many people have reported it @ 14-15%. I rode it last weekend and was grinding in a 34x25…immediately ordered a 12x28 cassette the next day, (I am a FOP cyclist and above-average climber).
Someone videotaped the new sections last weekend…check it out for yourself.
15-20% grade? Says who? Nobody is getting up that with anything less than, say 39/26 gearing at a minimum. Unless there’s only a 20yd stretch that is that steep.
Alpe d’Huez is like 8%, for comparison, with the steepest bits around 14%.
This is rural wisconsin. Some crazy steep sections of road. I did not measure the grade but people who have looked up topography said 15-20%. I road it in a 39/28 with a group of pretty strong riders and 3/4 ended up unclipping and walking. I was climbing standing in the 39/28 and my heart rate was 20 bpm over my IM target. If it was off road it would have been a granny gear on a mountain bike.
15-20% grade? Says who? Nobody is getting up that with anything less than, say 39/26 gearing at a minimum. Unless there’s only a 20yd stretch that is that steep.
Alpe d’Huez is like 8%, for comparison, with the steepest bits around 14%.
The entire climb isn’t that steep, but the third “kicker” is pretty damn steep (and kinda long) and many people have reported it @ 14-15%. I rode it last weekend and was grinding in a 34x25…immediately ordered a 12x28 cassette the next day, (I am a FOP cyclist and above-average climber).
Someone videotaped the new sections last weekend…check it out for yourself.
Power13 I appreciate your comments. I am a middle of the pack old guy - usually 20.5 - 22 for 70.3. Have only done IMWI once and took it easy at around 19 mph average. I am a decent climber and did it in a 39/28 and was feeling like I was burning way too many matches. I have never thought of getting a compact crank set up, until the day that I road this hill. The thought of changing out cranksets for one hill seems ludicrous to me though. I am going to ride the hill a few times this weekend on fresher legs and see how I do. The day I road it was the day after a long run, so legs not fresh.
Edited to add: I watched the video. Does not do it justice. At the 2:30 mark you see a rider walking the hill but it really does not give you sense of how steep the grade is. I was calling people out on facebook for being whiny and complaining about this hill and frankly was annoyed with it. Then I rode it. When I had to stand and grind up the hill and most of the other riders unclipped, I knew it was serious.
A lot of people say to use a disc in pretty much all but the hilliest of races. Yet with this wisdom I see very few disc wheels or disc covers in races. I used a disc cover in IM Lake Placid a couple years ago. I was a rarity. Why weren’t more people following conventional wisdom… I have no clue.
