Marvin2Shoes
Member
Now that really is argumentative. You are truly brilliant, everyone else is an idiot, got it.
Just a rant on restrictions - Tired of non-involved regulators
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Mario Antony
Active member
.
Nevertheless:
You don't feel the drag...
I cannot show you data I don't have ...
Is there a point to continue?
I agree we disagree on the topic, and need to have data to backup my comments (as writen above).
PS: the same thing with internal gear hubs. Some say you don't feel, others swear they feel a lot!
You start to write nonsense, and about things you don't have experience, and the problem is the fact that I won't discuss with you?
Nevertheless:
You don't feel the drag...
I cannot show you data I don't have ...
Is there a point to continue?
I agree we disagree on the topic, and need to have data to backup my comments (as writen above).
PS: the same thing with internal gear hubs. Some say you don't feel, others swear they feel a lot!
charleyc
Member
"I've chosen not to acknowledge the substance of your comment, which completely contradicts the BS that I keep posting in this thread. Instead, I've opted to intentionally misread your clear statement about bike weights, emoji about it, and then continue on my busy day of huffing paint."
Mario Antony
Active member
Bike weight is one thing, drag is another.
Once there isn"t acceleration, weight isn't important on a flat trail/road.
Now... DRAG on drivetrain/motor, you'll notice it (if you're sensible enough). The only way to show this is measurement.
But, as said, no data ro back this, no one has measured it, so. please continue with the nonsense of weight, if it makes you happy
I knew this had been tested somewhere and i found it. It's an old (2019) test in the Finnish Fillari magazine, but it will give you an idea. I'm pretty sure newer motors are not worse.
Even surface, average speed 28,5 km/h. Average wattage:
Bosch CX: 194W (gen2 Bosch with small chain ring, known to have major drag)
Brose Drive-S: 128W
Shimano E8000: 130W
Specialized 2.1: 125W
Yamaha PW-X: 137W
Pässilä Bicycles Kytö (reference acoustic bike): 123W
So if a few watts means hitting a brick wall , well, as it has been said many times - it's in your head.
You still didn't answer my question, what do you expect to happen when you hit the limit? Keep going as if nothing changed?
Mario Antony
Active member
Thank you for the data.
Not calling +70W too much drag, it's really not vert smart, and more so, if a Bike is only using ~120W.
This means Ebikes equiped with Bosch, has to spend +50% power just to keep up the 28km/h.
So, in reply to your post, yes, the drag it's almost a "wall", because besides the motor drag, you need to imput ~70W further, just to maintain 28km/h.
So, perforning an inverse calculation, if you were to imput 200W in a Bike, it would propel the cyclist little bit bellow 35 km/h.
So... it's 28km/h vs 35km/h.
Again... if you don't feel 70W is big, or +50% more power is big, the speed difference is a huge difference.
Anyone can do this experiment easily and check what I'm writting about.
What I want from engine assistance once reached 25km/h?
I want/wanted a gradual decrease in assistance, so that the drag won't be noticeable.
A bit like what Specialized did on 48V motor.
The graphic bellow, from Velomotion Youtube channel, shows the difference between Specialized Gen4 motor (48V) and Bosch "Gen5", regarding assistance over speed limit.
In all thruth, once reaching 25km/h, the motor could assist, to compensate the motor drag.
I believe motor drag will be reduce in coming years, but presently, it's something noticeable, and with your data to back up, it really shows what I (and all) "fight" to overcome 25km/h - at least on Bosch motors.
PS: I tried a hub motor, and drag isn't as noticible as Bosch.
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LeftItLancs
Active member
It would take 150 to 200w to maintain 25kmh on a 'normal' bike, therefore it takes fewer watts on an ebike but 'feels' like drag because +100 extra watts has to be applied by the rider after the engine cuts out.
I do agree it feels like drag btw.
It still takes significantly less effort to maintain 25kmh on an ebike compared to a 'normal' bike because the engine is sharing the load and offsetting rolling resistance, etc.
Reading between the lines in your post you seem to be saying, (and I could be wrong), you want to ride faster than 25kmh with minimal effort.
Mario Antony
Active member
As per Sherman Post, and in accordance with the Fin. magazine, it's ~ 70W difference @ 28.5km/h. At this speed, there is no assistance.
194W (Ebike+Bosch) is 58% more than 123W (Bike)
~200W (Bike) = ~ 35 "ish" Km/h
No acceleration, wind, normal riding position, around 80kg rider, flat road.
With this data, we end the "feelings" arguments, to which I thank Sherman for sharing.
Yes, I believe Gen4 is better than Gen2.
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I really think you need to get your bike looked at. There is virtually no drag.
Yes, it feels like it because you go from assisted to unassisted.
Goflst out in turbo, for 30 minutes then drop to eco, it feels like drag because there's such a vast difference on assistance, but you can't say eco is drag.
The motors have a clutch, everything disconnects !
You're cherry picking with the gen2. The chainring turns at a different speed to the cranks so in that instance, yes, there is some drag due to the unusual design.
Ignore that and you're looking at 5 to 10w difference , so nothing in the scheme of things.
Your previous argument of proving it by spinning the motor backwards is irrelevant. We don't rise like that so the clutch isn't disengaged.
As everyone has said to you over 4 threads and 49 million responses, take the chain off, rotate the cranks forwards - no drag.
If you have drag, your motor is faulty.
Mario Antony
Active member
Well, let's see the data, please.
But since we're in the "feelings" department, I would appreciate if you could post, a footage of that "free spining without chain". It's to compare with mine, and of course a Bike. Thank you!
PS: I set my Eco @50Nm and Tour @70Nm. Usually ride on Tour, dropping into Turbo/eMTB when needed.
charleyc
Member
Mario Antony
Active member
Being data driven, it always surprises me group bias, based on "feelings".
But please, let's continue the discussion, it's amusing!
Actually, it is data driven, and that data (apart from the one outlier from 2014) says that drag is minimal, a few watts.
Have you taken the chain off your e-bike yet and rotated the cranks the way you’d pedal them?
I think we’re into this territory now;
Mario Antony
Active member
Really? We now have parots?
You just rant without thinking...or reading?
At this point we've got:
@28.5km/h
#1 - Bosch Gen2 making +190 Watts
#2 - Bike making +120 Watts
(Being watts a measure of power, that measures the amount of work per time)
#1 - Bosch equiped with Gen2 is using +50% than a Bike
#2 - @190Watts on a Bike, you will be riding at +30 km/h
(km/h being a measure of speed. Meaning the amount of kilometers you travel in an hour).
In conclusion:
Yes, there is drag from the motor.
But as said, if it suits you, and you feel happy "feeling" no drag... Please, don't let my words affect you, and stay in your "confort zone"
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Why are you focused on the Gen2 Bosch, which is known (through its early design) to have significant drag?
Why are you not looking at the E8000 which requires only 7w more to propel at the same speed as the reference bicycle?
I think we know why, and I guess you’re at that point where you’ve lost your sense of humour and all you’ve got is personal insults…
Off you trot then.
Power1tobe
Active member
Finding this thread has been the bright spot in my day, as I love when I find posts where people really have no idea / clue what they are talking about. I mean you have repeatedly demonstrated you don't understand the term drag "Drag". So let start with a basic definition of term drag as "a force acting opposite to the direction of motion of any object moving with respect to a surrounding fluid. You generically state eBikes drag... but all bikes drag. So what in a eBike drags that doesn't drag in a regular bike? Not the motor, as it disengages once you stop peddling (Or at least mine does).
A bike can experience several types of drag to include: mechanical drag (this is not referring to a motor), rolling resistance, and aerodynamic drag. These can further impacted by weight / rolling surfaces / and inclines. Regardless, and generally speaking if those factors are held constant then an eBke & normal bike will experience the same drag profiles. Physics 101
Now because most eBikes weigh more than normal bikes, like my MTB weighs 26Lbs and my eMBT weighs 50Lbs, the eMTB will experience more drag (a little more rolling resistance), BUT... it also it will require more energy from the rider due to increased MASS. Increased mass increases the amount of force needed to overcome Inertia and Gravity, leading to higher energy expenditure. So maybe the word we are looking to describe is Inertia and its relationship to mass? The great the mass the more energy is required to overcome Inertia and get the bike moving and additional energy is required to keep the bike moving.
Another thought I have is that Class 1 eBikes that cutoff at 20mph have an abrupt feeling when you hit the thresholds, requiring you to transition away from assisted power to 100% Human power. But this still isn't drag.
Also the way you describe above the differences in how how different motors feel isn't drag, its the mechanical profile of the motor which can change based on electrical input power. It other words you can dial that up and dial that down(make it feel easy or hard) and change that feeling, but that not drag on the bike as its not a force acting against the bike.
Thoughts?
Mario Antony
Active member
Please, read the posts...
Any bearing or gear has Mechanical friction, to which I've refered as drag
So, we've got data, to corroborate the statement, to which some have refered to be an old engine (Gen2).
But, looking into each Bosch engine gen2 and Gen4, quickly verify there ain't so many differences, to which the values presented for Gen2, won't be too far from Gen4.
So, unless you've got a set of torque sensing pedals...
charleyc
Member
Everyone posting in this thread in good faith agrees with you. Mario is either trolling or simply unable to rub two neurons together.
In either case, don't waste your time trying to change Mario's opinion, just point and laugh.
Erm... No. Like completely not.
You keep telling people to read things yet you are incapable of reading that the gen2 has a chainring which doesn't rotate at the same speed as the cranks so has a large extra loading compared to EVERY other motor.
The very post you're happy to take data from also clearly shows that most motors have insignificant resistance compared to other bikes because the clutch separates all the mechanism from the cranks.
There is no drag. If YOU have drag, thats a fault on your bike. Or your psychosomatic issue.
@Moderator can you check his IPs please.
Mario Antony
Active member
It's the only data we've got (it didn't go your way, so... once more, feelings don't mean anything).
I've focused on Bosch, because it's what I have more experience/own presently.
You state it's a different engine because it rotates at different speeds, but the real issue, is the amount of bearings and gears you have inside the engine.
It's these bearings (and bearing seals) and gears, that reduce the efficiency and leads to the "dragging effect".
You don't feel... well, as said, NO PROBLEM TO ME, as the saying states:
"Each one knows about themselves, God knows about everyone"
But why requesting an IP address?
If you can't stand on your points, move along...
IPs are correct, user appears genuine.
However, @Mario Antony, without being disrespectful to your own experiences - motor drag on all the newer motors and most of the old ones is completely negligible.
You appear to be using the slothful induction fallacy to create your own argument and effectively turn this and other threads into your own personal soap operas whilst completely ignoring all the facts and most importantly - reality !
As has been stated by others, if you are experiencing drag from your motor with the chain off and the power off, you have a faulty motor.
For the sake of the sanity of other forum members, please stop your flat earth claims. Continuation will result in a 2 week ban for wasting everyone's time.
Thread will be locked as it's been hijacked and taken completely off track with this infantile and endless circular baiting rant.
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