[kil0ran]

I recently swapped my Defy Advanced (carbon) for an aluminium Domane (because winter). The bike fit is almost identical on the Domane, and I’m rather foolishly still running summer wheels/rubber (Fulcrum DB4s with exposed bearings, GP4000s tyres) – same combo as I had on the Defy. There’s not a huge amount in it weight-wise and yet the Domane just feels so damn slow compared to the Defy. This is borne out by Strava times on my regular routes.

So what it is that makes a bike dull, slow, and lifeless? Or is it all in the mind and body of the fool pedalling it? Granted I’ve been off the bike for most of the month due to a virus but I wouldn’t expect to be over 2mph average slower on routes I’ve ridden for years. It just feels like the Domane needs more coals piling on constantly and doesn’t respond to increased effort in the way the Defy did.

Topic

[IanEdward]

Interesting, I don’t get on
Interesting, I don’t get on with my winter bike either, almost exactly the same fit as my summer bike and my gravel bike, but always seem to end up with more low back issues. I’ve put it down to long slow steady rides in a fixed position instead of summer rides where I usually mix it up with hills etc.

However back to the OP – how are the drivetrains? I saw an interesting YouTube video that seemed reasonably credible and suggested that there could be 10W difference (ish) between two otherwise reasonably well maintained drivetrains. I doubt 10W would add 2mph but (I think) I notice the difference when I refit a freshly waxed chain…

[Gimpl]

I’ve posted before that I

I’ve posted before that I have two Defy’s, an aluminium one set up for winter now with cheaper wheels, mudguards etc and a Composite 1 set up for long, comfortable summer rides. I’m always a gear lower on the alu one, in part due to the wheels but also clothing, air density, temperature and so on. Long ago I gave up trying to compare the two, they have different purposes and I just roll with it. 

Originally I bought the alu one as a frame, seat post and fork (both carbon) and took everthing else off the CF one, wheels, groupset, handlebars. The only new thing was the cables. The ride was without doubt more ‘buzzy’ on the alu one even with all the same gear. Nowerdays I simply can’t compare the two as I’ve changed too much on the CF one. 

[kil0ran]

This is exactly how I’d

This is exactly how I’d describe the feeling I get on the Domane. I have a feeling it’s because it doesn’t leap away under effort changes, I don’t get the same feeling of a kick as I did on the Defy. It’s like that feeling when you’re not yet quite on top of a big gear.

[Xenophon2]

Assuming only modest

Assuming only modest differences in weight, I think small differences in geometry, setup, gearing, wheels/tires and fit can subjectively feel significantly faster or slower and have a real impact.  I once received a bike from a very reputable brand on loan while the regular was in the LBS for a couple of days.  I actually looked forward to giving it a spin.  But…it felt like if I was facing a 20 mph headwind the entire ride home (26 km).  Garmin later showed me that there was no headwind to speak of and my speed was indeed about 2 km/h slower while the effort felt a lot harder.  I don’t think frame materials by themselves matter a lot if the frame is properly designed and the weight is comparable.  

[kil0ran]

Well, a bit faster on today’s

Well, a bit faster on today’s identical ride, but still 1mph average off the Defy times. I did make a minor fit adjustment (10mm shorter stem) which made a big difference to hand and lower back comfort. 

[kil0ran]

Thanks Ian. Definitely not

Thanks Ian. Definitely not the wheels/tyres as I’m still using the summer wheels I used on the Defy. Bearings still surprisingly good considering they have minimal sealing (Fulcrum DB4s). I’m feeling more beaten up by the Domane compared to the Defy despite having transferred the position over almost exactly so I guess that just goes to show how all that D-Fuse stuff really does make a difference.

[CyclingInGawler]

I didn’t ride it quite that

I didn’t ride it quite that heavily loaded very often. The trick then was to avoid too much of a rocking motion; treating each day as a marathon rather than a sprint, and just spin up the hills. 

[David9694]

Did you not get some “whip”

Did you not get some “whip” when loaded? It’s why they developed 531ST.

[IanMSpencer]

Adding to the list, wheels

Adding to the list, wheels and condition of wheels is a biggy. If a wheel isn’t in good condition, loose spokes will sap energy. Heavy rims and tyres will sap energy. Knackered bearings allowing the wheel to flop about won’t help either.

If you can, and with rim brakes and rotor differences it is not always straight forward, try comparing wheelsets between bikes, that might help pin down major differences.

Looking at the frame stiffness discussion, there are a couple of key places where rigidity is important, but elsewhere softness gives ride comfort gives pace over the long term. The Defy does seem to have a great combination of a complaint ride, yet there is a torsional rigidity between crank and rear wheel – so the seat is loosely coupled to the rear wheel, but the pedals are quite rigid. If you are feeling brutal, step on one pedal while off the bike and see how much you can flex the frame against the rear wheel – there will be quite a bit of movement even on a stiff bike.

The comfort of the ride should not be dismissed. If you are getting uncomfortable from your bike, you are going to have to work through that discomfort to apply effort. The Defy has a gentle cockpit, so no buzzing fingers and potential RSI type injuries, and the compliant seatpost combined with the right saddle allows you to sit without needing to fidget and stand to protect your backside.

So a well maintained, comfortable bike that is a pleasure to sit on will deliver performance over one that lacks those things. I’m not a great believer in professional bike fits for the happy amateur, in part because a lot of bike fit theory is built on performance rather than comfort and endurance – I have evolved a bike position that suits me and is transferable between bikes and allows me to regularly ride long distances – I doubt it is “optimal” for performance, but I can get off my bike after 80 miles, have a shower, and carry on doing stuff without moaning and groaning. That being said, evolving a good position is important – listen to your body.

[hawkinspeter]

marmotte27 wrote:

marmotte27 wrote:

The video only shows that/how the energy is stored. The amount of energy absorbed through a temperature rise by the frame will be so small as to be negligible. With a frame flexing at the rate of 90rpm I’m your pretty sure you’re not getting even a temperature rise of 0.01°C. It has been shown that riders put out more power on flexible frames : https://www.renehersecycles.com/the-biomechanics-of-planing/ (Just in case : please don’t come out with any René Herse bashing now, without providing contradictory sources of at least equal quality.)

That’s much more like it. Finite element analysis and double blind testing, but shame that the issue isn’t online: https://www.renehersecycles.com/shop/print/issues/bq-24/

Now that I can see that there is some science/explanation of the benefits of flexy frames, I’m much less sceptical of flexy frame anecdotes.

[Anonymous]

The video only shows that/how
The video only shows that/how the energy is stored. The amount of energy absorbed through a temperature rise by the frame will be so small as to be negligible. With a frame flexing at the rate of 90rpm I’m your pretty sure you’re not getting even a temperature rise of 0.01°C.
It has been shown that riders put out more power on flexible frames : https://www.renehersecycles.com/the-biomechanics-of-planing/
(Just in case : please don’t come out with any René Herse bashing now, without providing contradictory sources of at least equal quality.)

[kil0ran]

It’s a good point – for a

It’s a good point – for a time during the bug I had a resting heart rate of 90bpm (usually low 60s) and a temp of 39.6C. But the bike “felt slow” before that.

[hawkinspeter]

Backladder wrote:

I want to see them do it again with the pedal at the bottom of the stroke, because that is where the frame tension is released in normal riding, that experiment only works because the crank arm is nearly horizontal.

I wonder how much of the flexing is the frame/bottom bracket and how much tension is stored in the chain and brakes. With the crank vertical, there should be no tension in the chain and no need to apply brakes, so I agree and think that experiment wouldn’t work.

[Backladder]

I want to see them do it

I want to see them do it again with the pedal at the bottom of the stroke, because that is where the frame tension is released in normal riding, that experiment only works because the crank arm is nearly horizontal.

[Ride On]

On day 23 of the virus now
On day 23 of the virus now,feel mostly over it but my cycling and running VO2 max estimates on garmin have dropped dramatically and my resting heart rate is still sitting 7 points above the average for the year. So dont underestimate the impact of seasonal bugs you are fighting.

[Author]

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