What is the real speed difference between high to low end road bikes?

[fatjel]

freiston I tend to go out for the same ten mile ish ride most mornings so seems a reasonable comparison . The spa has mudguards rack lights and is a couple of kilos heavier because of that. The spa is my bad weather bike so subsequently I rarely ride the roubaix. When I do it feels significantly easier to ride and more comfy.

 

[Ming the Merciless]

Wow! It's a big difference then!

If you put in 160 watts on the flat you’ll get to about 17.2mph. If you put in 190 watts you’ll get to about 18.4 mph. That gives a 1.2mph extra for those 30 watts.

 

[Alex321]

If you put in 160 watts on the flat you’ll get to about 17.2mph. If you put in 190 watts you’ll get to about 18.4 mph. That gives a 1.2mph extra for those 30 watts.

Which is about 8%, so quite significant.

 

[Pumpkin the robot]

Good question, it's more precise, faster and a generally nicer experience. It's probably easier to try it out and see how you get on, rather than me try to sell it to you.

I suspect the people on here advocating electric gears have them, but also have or have had bikes with mechanical gears, so have experience of both and are able to a lived experience of both sides. But it's possible the people questioning the benefit of electrical gears over mechanical and whether or not it is worth it etc. very possibly don't have the experience of them.

Personally I prefer electric gears but everyone is different. Try them out and see how you get on.

I have done about 30k miles on my di2 equipped bike, I have some experience of it
My winter bike has mechanical gears and I do not notice a drop in performance from di2.

 

[Ming the Merciless]

Which is about 8%, so quite significant.

7% but that’s by the by. I wouldn’t call 1 mph significant. Plus we have to ask what it causing the difference. It’s certainly not the gearing as per the OPs claim.

 

[Dogtrousers]

7% but that’s by the by. I wouldn’t call 1 mph significant. Plus we have to ask what it causing the difference. It’s certainly not the gearing as per the OPs claim.

It's depressing isn't it. 30 watts represents about a quarter of my usual range of efforts (between gentle and hard, but not including "really pushing it" or "idling/freewheeling"). And it yields a measly 1mph increment.

It's a significant increment in effort for an insignificant return.

 

[Alex321]

It's depressing isn't it. 30 watts represents about a quarter of my usual range of efforts (between gentle and hard, but not including "really pushing it" or "idling/freewheeling"). And it yields a measly 1mph increment.

It's a significant increment in effort for an insignificant return.

You really do need to look at it as a % increase rather than thinking of it as "just" 1mph.

 

[Ming the Merciless]

It's depressing isn't it. 30 watts represents about a quarter of my usual range of efforts (between gentle and hard, but not including "really pushing it" or "idling/freewheeling"). And it yields a measly 1mph increment.

It's a significant increment in effort for an insignificant return.

It is . I’ve noted when I’ve gone for it. You don’t really gain that much speed. Plus your fuel per mile is far far worse. Far better to keep the effort manageable. If the ride is of any length you’ll likely get there in a similar time having had to stop less to eat. Plus feel much better.

 

[Dogtrousers]

It is . I’ve noted when I’ve gone for it. You don’t really gain that much speed. Plus your fuel per mile is far far worse. Far better to keep the effort manageable. If the ride is of any length you’ll likely get there in a similar time having had to stop less to eat. Plus feel much better.

The reverse happens too I guess. If I was doing a 200k Audax on a lighter, racier, faster (possibly more expensive) bike the "free" speed that I've got for my money (let's say an extra 30 watts worth) isn't worth much in raw speed. That extra 1 and a bit mph would get me round - depending on how fast I was in the first place - about 30-60 mins quicker*. All other things being equal, like comfort and practicality, punctures etc.

Being a lazy rider what would probably happen is that I'd notice I was going a bit quicker on my new fancy bike and subconsciously back off the effort level to my usual speed so I'd get round in the same time.

* This could be the difference between "food left" and "no food left" at the finish, so could be significant in terms of free flapjacks.

 

[fatjel]

On a 2 or 300k audax the difference between the carbon verses steel bike is comfort related.
The pain kicks in later on the more expensive bike. Which was the reasoning behind the build

On the mountain roads around here every kilo saved is very noticeable too

The power meter was for sure the least useful item I have ever bought for a bike.
In my defence it was lockdown and I was very bored

 

[Chislenko]

If you go by my performance on my "good bike" this morning then the difference is........bu--er all 😟

 

[Mo1959]

If you go by my performance on my "good bike" this morning then the difference is........bu--er all 😟

Lol......yep, it's more how my legs are feeling that determines my speed rather than what bike I am on these days.

 

[CharleyFarley]

I'd guess that the most accurate way of comparing low end and high end bikes for speed would be on a dynamometer, if such a thing is made for bikes. (They're made for motorcycles.) A dynamometer, used indoors, would not be subject to weather conditions such as wind, or to gradients and road surfaces.

 

[C R]

I'd guess that the most accurate way of comparing low end and high end bikes for speed would be on a dynamometer, if such a thing is made for bikes. (They're made for motorcycles.) A dynamometer, used indoors, would not be subject to weather conditions such as wind, or to gradients and road surfaces.

Isn't a smart turbo a bit like a dyno with added road load simulation?