bruce19

I am also primarily a road rider. About 4 yrs ago I went to tubeless. More accurately, I saw a killer deal on Mavic Ksyrium Elite USTs and, because I was skeptical, I only bought a rear wheel w/tire. I put it on my Guru Sidero and went for a ride. I was stunned. It felt quicker to spin up and more comfortable. To give you an idea of who I am as a rider,...I am 76, 5'9"" and 188 lbs but can still do a 1 mile flat at around 25 mph. On a great day I am a mediocre climber. I no longer ride for distance and will usually do 3-5 rides a week at 15-25 miles. Most of my riding could be called HIIT. Not that I'm particularly fast, I just enjoy pushing myself. But, back to the subject. I found tubeless to be quicker, lighter and more comfortable. So, I got a front wheel and then a set for my CAAD 12 and my wife's Colnago road bike. In 4 yrs we have zero flats. I've never had a problem with sealant or inflation. I basically don't do anything but top off with air and ride.. Tubeless has been the best mod I've made in 40 yrs of cycling.

merlinextraligh

cough, cough, bulls*** , cough, cough.

Placebo. You can run the numbers as long as you want, a change in rolling resistance, and a weight savings of maybe half a pound cannot give a 7% bump in performance.

merlinextraligh

Rolling resistance is only about 10% of total resistance, and that % goes down with increased speed, and climbing. To get the 7% claimed increase in performance, you’d need a 70% decrease in resistance. No one claims that the lowest rolling restance setup makes anywhere close to that gain. Moreover, the IRC tires aren’t particularly low resistance. https://www.bicyclerollingresistance...-tubeless-rbcc

it can’t be an aero advantage. Going from a basic wheel to something very aero like a Zipp 404 would be worth a few seconds on your 12 mile course, and your Kinlin Rims are no where near as aero as a deep sectioned carbon rim.

As for weight, even assuming a very charitable one pound savings, the difference is only 1/200th or so of the total system weight. That would be worth a couple of seconds over 1200 vertical feet, but give you no advantage on the flat portions.

Going from stock wheels/tires to an nice but not great wheel set just does not result in a 7% increase in speed.

Perhaps you felt faster on the new setup, encouraging a more aggressive approach to your ride, and a more aero position on the bike.

eduskator

Comfort, probably. Speed, probably not.

Wouldn't ''go'' tubeless if I had tubes. My road and gravel bikes came tubeless so I stay tubeless.

Maelochs

Perfectly reasonable if his FTP was about 40 watts to begin with.

cyclezen

You know, this all makes perfect sense, can't really be argued, and should provide some guidance.
BUT, I have 2 tarmacs (in the US) , a 2009 expert w/10 spd Ultegra and a 2012 Comp with 10 spd 105. The are both FACT 8 CF, one has HED kermesse wheelset, the other HED Ardennes (21 width internal) and similar good tires, same cogsets, kermesse are 5 oz heavier ttl wheelset weight... Setup/position is about as identical as possible. I am a stickler about 'riding posture', so constantly aware of maintaining what I believe to be good riding posture for me. The 09 tarmac weighs just about 19 lbs with pedals and accessories (no water bottles), the 2012 tarmac weighs about 18 lbs 7 ish oz...
YET, the 2012 tarmac always proves to be 'faster' by 8-10% ride avg time, for the same route and roughly the same evironmental conditions. That's a lot ! On an 'off' day the 2012 might be just as 'fast' as the 2009, but is hardly NEVER slower... Is it me? the Wheels? the tires? There are times when I'm actively trying to get the 2009 to reverse that result. Really hard to do.
I don;t have a PM, I ride with a HRM, and watch HR closely, the resulting ride graph results of HR is often close to identical - yet the 2012 is faster...
BTW, I recently changed out the light Butyl tubes from the 2012 and went to TPU - so far no discernible 'betterment' due to TPU lighter weight/ride.
However, I am climbing better - but that's due to general physio improvement, my climbing has improved about the same on the 2009... so not a difference maker.
attribute to small gains in many areas ? I can't think what else it can....
My take-away - ride the 2012 whenever I want to be at my best... Ride the 2009 a lot, to push me to improve , more. The 2009 is my midweek ride, the 2012 is my weekend ride.
... I have checked and made sure all the running gear/drivetrain/wheel dynamics are in top form on both bikes...

Another take-away - Experiment a lot ! If you have the money and the inclination to learn or be puzzled, experiment a lot.
Ride Tubes, ride tubeless, latex, TPU. ride super high end rubber, ride medium price rubber, ride different sizes... try different saddles, stems, bars, just about everything.
Then pick what you like and think works for you - and continue to experiment !
I try not to be an apostle of 'one thing', because I've had to change in so many ways and so many things, over the years... I'm not sure if that's wise, but it is fun!
The science is interesting and great; but often changes in real life when my rubber meets the road. Probable consequence of Rube Goldberg machine - my body...
Ride On
Yuri

Maelochs

Dude .... Science.

Swap the wheels.

Also, unless they are Exactly the same frame, not just the same designation .... is it possible the manufacturer made minor upgrades over a three-year period? I don't know.

Ten percent is a Huge gain in speed. Ten percent is way more than the winning margin in most grans Tours ...... Maybe you have a Magic Bicycle?

Swap the wheel and see if it is wheels/tires.

Then swap the drive trains .... if the gearing is the same on each, then it is hard to imagine That would be the difference....

Then try balllasting the 2012 to the same weight as the 2009 and do a dozen runs or so .... then maybe swap the forks?

Maybe it's all psychosomatic---you know you are on the "faster" bike so you dig a little deeper? Get a friend to ride them both for several days running.

We are counting on You to find the answer.

cyclezen

Yeah, I've already done the wheel swap, and there is a slight change towards equalization, down to about 5-6%. So when either wheelset tires wear out, I'll put on same as other wheelset and then do the wheel swap again.
Drivetrain swap? I'm not that interested... LOL!
weight equalization - again, I can't see that 9 ounces is gonna be it (might be part of IT...)
If anything, when I'm on the 09 tarmac, I might be trying to 'equalize the effort', try just a bit harder, without being a noticeable greater effort - hasn;t helped/worked.
Yes, the frames have a few, slight differences, most things almost identical, except the HT on the older is 1 cm taller, but I'ce compensated for that by equalizing the bar drop, other stuff is similar/same DIMS. The newer is discernably 'stiffer' - not talkin in the ride quality sense, but in what appears to be less frame deflection on hard pedaling... But, really, the tires would absorb most of any drive difference...
I'm guessing it will be the tires... but an 8, almost 10 % difference seems way too much...
When one tire set wears down, I'll match the tires, and try again...
Ride On
Yuri

Maelochs

Well, it seems wheels and tires (assuming you swapped wheels With tires, but maybe you dismounted and remounted both sets of tires ;D ) are about half the difference.

Other little things like frame rigidity must be adding up. And assuming that a more rigid frame will perform the same as a less rigid frame because .... "tires" ... makes no sense. Reductio ad absurdam suggests that a frame made of 1/2 inch titanium, , wet spaghetti, or carbon fiber would all react the same because of the tires .... ********** I'd say you have half the difference in the wheels and tires, and the rest in tiny things like a better frame.

Also, while you can apparently see or sense deflection under pedaling, imagine what you cannot sense but which is contributing. Common sense tells me (but we all know "common" sense is sometimes different for different people) that the frame has been decidedly upgraded, and not just in one area .... I have to assume the Whole Frame was re-engineered (I don't see the R&D team saying, "We need to work on the frame---lets just add another couple layers at the BB junction and call it a day.)

So it would seem based on your observations and my estimations, that the frame is new, different, or at least improved. And while I laugh at all the "Our new frame is .000037% laterally stiffer and .0003634 % more vertically compliant" claims, that stuff does add up to marginal improvements.

We might hope that one small change accounts for the difference, but more likely there are a bunch of 1% changes ..... also, one bike is a half-pound lighter than the other. Sure it is what 1/300th of total weight, but again, small increments accumulating ...... And given that the engine is the same a half-pound bike to bike is pretty large. Frame, tires, wheels, weight .... not much mystery here when one thinks .... that there isn't much mystery here.

As for fact, i don't have any.

vespasianus

I will only ride tubeless if Larry give it his blessing.

cyclezen

Yeah, tire wise, there does seem to be a difference in deflection. A soft comfy tire , aired down, does deflect more under hard bursts/power. A firmer, light tire always seemed to deflect less in these instances. Hence a lot of what was old school 'high pressure' airing the tires; we sensed less 'deflection', but sensing 'impedance' may be a much harder thing.
Plus as much as I like the Forte DC Pro tires on the '09, I know they're not as good/fast as the conti GP4000 or Rubino Pros I run on the '12... And the DC Pros seem to do much better at higher pressure - 90 psi as opposed to the current 75/76 I run on both wheelsets (72-75 on the '12 HEDs with RUbino Pro).
Also it's really hard to find a longer stretch of 'mostly flat' riding here, so there's a lot of lumpy riding... I tend to 'push' on uphill , especially if I know it's short enough to 'power' over. My 'flat' rides still have about 1K ft gain over 16 miles or so. only 'flat section is maybe about 1.5 mi. If I were to find a 'flat section' , the difference between the bikes might be negligible or at least quite close.
I also remember that when Tom Boonen and "Spartacus' started riding for Specialized, they both made significant contributions toward frame redesign - '09 was before that time, '12 was when the changes started flowing in.
You're right about 'small, incremental gains' - they accrue. They don;t change the overall enjoyment, but there's likley a signficant difference when there's a time/development span for materials which can be engineered.
thanks for the reminders and view for another perspective...
'experiment', always some fun! winter around here, a good time for foolin around with tech.
Ride On
Yuri

alcjphil

And what effect will that have. Do you expect that his blessing will affect your performance?

terrymorse 

Approval by Larry is worth at least an extra 10 Watts.

It’s basic physics.

eduskator

I had my first flat in well over 5000kms yesterday on my race bike with TL tires. Needless to say that tubed or TL, my tires didn't stand a chance against this huge rock.

vespasianus

New around here?