Smokehouse

I finally got to road test my new Specialized CG-R seatpost...holy hell is that thing comfortable! It completely shut up my bike and silenced all of the vibrations I was normally getting through my arse due to crummy roads.

100% worth the $$ and instantly noticeable upgrade.

Of all the things I've bought...this has been the most useful thus far...followed by good tires...

rpenmanparker 

Good for you, but my experience does not agree with yours. Going from 19 lb steel to 14 lb carbon with 1,270 g wheels I see absolutely no effect on my performance. Zero, zilch, nada, zippee-do-da. Riding your loop on a given day on both bikes would be a telling experiment. Maybe two days in a row, new bike first one day and second the next day. Average the results for each bike over the two days and compare. Personally I don't believe it.

clones2

After riding and time trialing the same loop for 6 months and never being above 18.15 mph - and all of a sudden I gain 2 mph - never under 20mph avg again.... Well..... it wasn't the kale chips...

rpenmanparker 

Until you make the head-to-head comparison, you can never know. Also if you have downhills and tight corners, it could be handling.

canam73

I won't dispute your times, but I think you are allocating to much improvement to weight and stiffness and not enough to "a little aero". And I'm mostly thinking the aero improvement was lower bars and other position and fit improvements.

Bandera

The only meaningful performance of a "race style bike" comes when you pin on a number and compete, that's what they are for and gains are accurately measured in placing at the finish line. Did you expect some other metric?

-Bandera

Carbonfiberboy 

I have a 21 lb. aluminum rain bike and an 18 lb. carbon bike, identical drivetrains. I notice no difference between them other than the carbon is smoother and climbs nicer, but I don't think faster or at least not noticeably. However! Years ago I went from a 27 lb. 80-something 12 speed to that carbon bike and oh yes, I could tell the difference. I was very noticeably more competitive on my weekly group rides. Who wouldn't be if they dropped 9 lbs? More important than the weight was the stiffness. I've recently dropped 13 lbs. body weight and same thing, yes I sure can tell the difference. But a couple pounds, I don't think one would notice it if stiffness, wheels, and tires were the same. As others have pointed out, the bicycle industry will pay you $500 for every pound you lose off your body. That's a great ROI. Buy a decent bike and lose weight unless you already look like Wiggens.

All that said, I do notice a difference with aero wheels and spokes and with tires. I'm a tiny bit faster over long distances with better wheels and lower rolling and wind resistance tires. No power meter, but I can tell the difference. Most of this difference can be achieved with little or no additional cost when normally replacing stuff as it wears out. An alu aero rim is little more expensive than a box rim. Aero spokes are more expensive, but they last a long time. Not that big an outlay for modern low count wheels.

And as others have said, fit is a big deal. Being able to hold power levels for a long time is a function of fit. And if aero wheels make a small difference, it's dwarfed by fit. Just pedaling knees in is worth $2000 in aero wheels. Getting your back flatter is even bigger.

Long Tom

Quantitative? Bah humbug. Let's talk qualitative. My good bike is light years ahead in that regard. What, my feelings don't matter?! Sheesh.

gregf83 

It also wasn't due to the bikes. Your position changed and you may have put out more power. More power alone would be unlikely to account for the difference so it has to be primarily based on your position and other aero effects. You mentioned you raced for the first time. Learning what it's like to suffer also helps.

Even the most optimistic marketing types wouldn't make a claim for 2mph improvement.

MegaTom

Time on the saddle.

Then speed, power and fewer lbs to carry eventually followed.

bonz50

not saying I agree with a 2mph in 4wks because of equipment, but......... his position on the bike changed because of the new equipment, right? sure he could have got that aero position with a good fit from a reputable shop, but also, the geometry of the newer bikes may have been more optimal for his body type and allowed him to transfer more power. there are a lot of variables that could be attributed to the "equipment", but likely the old equipment was holding him back for many reasons, could have been poor wheels, poor fit, etc. but the newer bike "fixed" that problem so, while I tend to believe that all else being equal (fit and etc) changing bikes won't net a big gain like that, but if those variable are not the same then the new bike was responsible for his improvement even if it was because it was more suited to him.

merlinextraligh

I highly doubt that. Lets say you go from a heavy set of wheels to a very light set of wheels and shave 500 grams (more than a pound)

Assume fairly average rider power, and rider and bike weight. The 500 gram lighter wheels make an 11.44 second difference over the 6.5 miles
Analytic Cycling, Interactive Methods for Estimating Cycling Performance Parameters. Tom Compton

Now there could be some other differences, but they wouldn't make a 2 minute difference, particulary climibing a 6% grade. (i.e. the new wheels could be a bit more aero, or have less hub friction)

merlinextraligh

You got some small improvements from the weight decrease, more aero wheels, and possibly to a lesser degree from less mechanical friction in components and tire rolling resistance.

Then there's the plecebo effect of getting a new bike, and another possibility that your speedometer on the new wheels isn't calibrated to those wheels/tires.

To the extent you actually are 2 mph faster, dollars to donuts it's 90% or more due to the position on the new bike being more aero.

merlinextraligh

There actually is data available to figure all this out, and the answer is going from a 25 lb bike with entry level components to say a 17lb bike with better wheels, tires, components will make you faster but it's not the big change some people expect.

You can run all of theis for yourself at www.analyticcylcing.com or Bicycle Speed (Velocity) And Power Calculator

8lbs off the bike will make over a minute a mile difference on 6% climb. It will make a 2 second per mile difference on a flat road. (perhaps slightly more in a situation where you're accelerating and slowing, such as in a crit)

If you put more aerodynamic wheels on the bike, that will be worth a couple of seconds a mile (varying by which wheels we're talking about, and how fast you ride) The data is out there in various wind tunnel tests. Wheels like Zipp 404's are about a minute or two faster over 40K at 30mph compared to 32 spoke box rimmed wheels.

Better tires on the more expensive bike will have less rolling resistance. The differnece in speed here will be smaller than the difference from the aero wheels because rolling resistance is a smaller part of the total resistance to moving a bike forward.

Better components will have less friction, but the speed advantage here is truly deminimis. Velonews has done varying tests over the years of bottom brackets, hub bearing, derailleur pulleys, and the difference between the best and the worst is small, and a very small part of the overall resistance to moving a bike.

So if you pull all that together. The 17lb bike with aerowheels wheels will be a couple of seconds faster per mile on the flats ( around .1-2mph) than the 25lb bike with conventional wheels, with most of that difference coming form the wheels.

It will be about .4mph faster on 6% climb.

It will accellerate with slightly less effort out of turns, or from a stop.

These are measurable differences, but not nearly as big as sometimes claimed.

bikerjp

Wasn't there a video posted a while back with an ex-pro or something riding different bikes (like a hybrid, some cruiser with a basket, etc.) and the difference between the road bike and the hybrid wasn't that much. I think he was racing someone and only lost when on the worst bike.

I think the performance gains are going to be fairly minimal. The perceived gains (or qualitative gains) are where you will see the biggest difference. Like most things, a nicer version is just that - nicer. A $5K bike is going to shift nicer and ride better in various subjective ways that are perceptible compared to a low end bike but we are talking incremental changes not huge differences unless we are comparing to a wal-mart bike or something. The biggest performance changes will be due to any physical gains from riding more assuming a better bike gets you out more.