Best ways to increase biking speed (Page 5)

Crr scales exactly like slope so every improvement in Crr of .001 is exactly like a change in slope of .001 (that is, 0.1%). That is, if you look at the power equation, it looks like

watts = crr * mass * g *v + slope * mass * g * v + 0.5 * rho * CdA * v^3 + acceleration

or

watts = (crr+slope) * mass * g * v + aero and acceleration stuff

That's why if you want to make a good estimate of Crr from field tests you'll want to know the slope, because the effects look the same. But in a larger sense, if you climb a hill, you often get to descend it while increased Crr is always there. Remember that the Crr you see in tables like AFM's are for smooth rollers so you have to multiply by a "surface roughness" for real roads; a typical multiplier is something like 1.5 to 2.0 though for really crappy roads (that's a technical term) it can be higher. The difference between a good rollling resistance tire and a poor rolling resistance tire (*cough* Tufo *cough*) can be something like .003 or .004 which over the length of an 180km IM bike leg is like climbing an extra 500m hill.

Duh!   We all have the same disease.

The point is if you want to get faster and you're in the teens mph, focus on fitness.  Buy the aero bike but expect to get the gains only as a function of higher speeds.

Try working with an online calculator for bike speed to come up with the time savings between various amounts of aero.

NO!!!!!  Expect the gains from aero INDEPENDENT of fitness.  Focus on BOTH!!!

As mentioned by Fred already, the slower you are, the more overall time you will save with aerodynamic improvments over the same distance as someone who rides faster.

Wow.  So much insanity in this thread.  I don't even know where to begin.

Ride lots of miles easy to get faster? Aero doesn't matter below 20 mph?

I'm leaving before I get banned for saying something mean.

Focus on both.

At 12mph *for you*, it's a very small effort.  30%?  Maybe even less.  If a TT bike / aero gear cuts that to 25%, no, you're not going to feel any difference.  It's all in your easy conversational pace.  You're still more efficient.   You just can't tell at that speed without a way to measure it directly (power meter).

Someone less fit might feel it though.

No single change is going to make a big difference by itself.  It's the sum of the parts that you're looking for.  Good position on the bike, helmet, wheels, tires, tubes, and so on.

You would probably agree a mountain bike isn't a fast choice to compete against other road bikes.  Well, it has a high combination of rolling drag and aero drag that you saw on the chart.

That's linear thinking, but its not game changing if you want to turn seconds into minutes and you're slow.

The real point is everyone in tri (virtually) ultimately has a good bike, and may get a great bike.  You will see low returns at low speeds if you want to improve your overall speed from aero at those speeds, whereas if you spend most of your time at low speeds you will have increasing returns if you spend time improving your fitness.  And then, on top of it, you will get an increasing return from the aero.

??? I'd like to see that calculation. Air resistance increases proportional to speed squared, hence more aero will benefit the faster rider relatively more. Sure, that's not the same as absolute numbers, but there is a point where both relatively and in absolute time the faster rider wins the most from better aero.

If you're a slow rider work on improving the engine. As for aero, take what you can get for free - free as in 0$.

a faster rider gains a larger percentage of time (minutes/minute), but a slower rider gains more actual time (minutes). 

On a pure hill climb you could probably follow that chart, it all depends on your speed. Andy Schleck might want the aero, you might want the crr, and everyone wants a lighter bike.

Actually, I don't disagree.  I'm not suggesting to wait to buy the bike.  I'm answering the question "Best ways to increase biking speed" in the added context of someone who doesn't yet have the fitness to really benefit from the bike.  And I'm being persistent because people are really confusing the physics on the low end - anytime you have a mathematical accelerator like a polynomial formula it is important to understand scale.  

If you're close to any cutoff, of course every iota of gain is worth it!

The main reason the slower rider gains more overall time is becase he's on the course for a longer period of time...thus experiencing the increase in speed (even though it's smaller) for a longer period of time.

Everyone knows that, but the air resistance doesn't go to zero until you stop. You also need to look at it in terms of time saved. So far it's been whether it feels hard or not. Try actually running some numbers through to see what you get.

Ah, I think I understand what you're asking. Yes, if you are limited in overall power (and aren't we all?) then since Crr scales like slope, on a steep slope an even larger proportion of your limited power is going to be spent on the "linear" component of power demand rather than the cubic component. On very steep slopes you may not be able to get your speed very high so you'll be trapped over on the left side of the plot. Is that what you meant?

Wow, look at the can of worms that I opened up...   I feel like forest gump now... "I'm not a smart man, but...." or Erkle, "did I do that?"

You guys are operating at several pay grades above me... LOL.

My anedotal evidence of the influence of gym work is this:

After my HIM race in late Oct. my season was done, I cut back on volume and intensity... then I had to do the El Tour de Tucson... my longest ride ever for the year was about 80 miles done once back in Aug., I did one long ride about 70 miles about 2 weeks before the El Tour.  Had a good race... then off season and in late Nov. I went to the gym and worked on leg strength and muscular weeknesses.  I cut back on biking by 50%, and upped my running a little bit in Dec.... absolutely no swimming.  I did the gym about 3 x a week.... Then in Jan, I started with an online coach and brand new plan... during the first couple weeks, I had to do the FTP tests and run tests...

Well the evidence was this... my 15 second sprint (and I don't practice sprinting hardly ever) went from 800w to 1250w, my 1 minute went from 350w to 500w and my 5 minute went up to about 360w, my 20' and 60' as well... how am I not supposed to think that the weight training had nothing to do with this?  Am I making the wrong conclusion?

But I'll also say this, I cut back on the gym stuff in late Jan. and a new plan from a coach had me do more lsd at 70% than I've done before and then when retested before Leadman, my 60' FTP went up from 295/300 to the new 325.  So I'll give credit to that... lsd sucks, it's boring and like chinese water torture, but it also seems to have worked.

I'd also give credit to riding more on my road bike, that has definately made me better too, all of the lsd were on the road bike.

My running hasn't changed that much either... the only thing that I'm able to do better at running is stay a threshold a little bit longer, but my pace hasn't improved dramatically.

Yes.  And I would suspect that the before and after results were not very good tests.  If your true 1' all out was 350w prior to weight training, you're probably closer to a 3-3.5 hour HIM bike split...or targeting a power much less than 150w. 

Yes, you are making the wrong conclusion, but not the one that you're questioning.

Strength training will improve your 15 second and 1 minute sprints significantly, plus it will have an impact on your 5 minute effort, because the shorter the effort, the more dependent it is on anaerobic energy pathways.  Efforts under 2 minutes are almost completely anaerobic.  Even at 5 minutes, anaerobic fitness has a large impact on performance capabilities.  The longer the effort, the less anaerobic fitness is a factor, and the more aerobic energy pathways are relied upon.  Strength training primarily utilizes anaerobic energy pathways.

Stop thinking in terms of training muscles, and instead understand that focusing on energy systems and specificity of training are what is important.