The Carrot Effect

[Jeremy McCreary]

Question: Do you sometimes notice a tendency to exert yourself more at higher assist levels?

Not because a hill or headwind demanded more assist and exertion at the same time. Just for the sensation of gobbling up ground at higher speed and leg power?

Happens often enough to me that I've come to call it the "Carrot Effect". It's generally not intentional. I just find myself in Carrot Effect and go with it till I run out of steam.

I recall at least one other mention of something like the Carrot Effect on EBR. I can only imagine what it must be like for a strong rider!

Good example from 2 days ago: Pedaling my power-sensing Vado SL 5.0 in ECO (35/35) on a flattish stretch of Coast Highway at around 160-180W — a (somewhat) sustainable exertion level I enjoy. Then bumped assist to SPORT (60/60) at a light just to start out but forgot to go back to ECO.

Next thing I know, I'm flying along in SPORT — not just at higher ground speed, but also at ~50W more leg power! Just happened on its own, but it felt so good that I kept it up for a couple of miles before easing off.

The SL seems to promote the Carrot Effect, and I very much like that about the bike. But the same thing happens from time to time on 2 different hub-drives with well-implemented torque-sensing assist.

I lump these 3 ebikes as having "exertion-sensing" assist (ESA) — meaning that they track rider exertion in the form of torque or power or both and dole out motor power accordingly. Guessing the Carrot Effect requires some form of ESA but don't really understand it.

Thoughts? Experiences?

 

[Rás Cnoic]

Question: Do you sometimes notice a tendency to exert yourself more at higher assist levels?

Not because a hill or headwind demanded more assist and exertion at the same time. Just for the sensation of gobbling up ground at higher leg power?

Happens often enough to me that I've come to call it the "Carrot Effect". It's generally not intentional. I just find myself in Carrot Effect and go with it till I run out of steam.

I recall at least one other mention of something like the Carrot Effect on EBR. I can only imagine what it must be like for a strong rider!

Good example from 2 days ago: Pedaling my power-sensing Vado SL 5.0 in ECO (35/35) on a flattish stretch of Coast Highway at around 160-180W — a sustainable exertion level I enjoy. Then bumped assist to SPORT (60/60) at a light just to start out but forgot to go back to ECO.

Next thing I know, I'm flying along in SPORT — not just at higher ground speed, but also at ~50W more leg power. Just happened on its own, but it felt so good that I kept it up for a couple of miles before easing off.

View attachment 184058
The SL seems to promote the Carrot Effect, and I very much like that about the bike. But the same thing happens from time to time on 2 different hub-drives with well-implemented torque-sensing assist.

View attachment 184059
I view these ebikes as having "exertion-sensing" assist (ESA) — meaning that they track rider effort in the form of torque or power or both and dole out motor power accordingly. Guessing the Carrot effect requires some form of ESA but don't really understand it.

Thoughts? Experiences?

That's a very good expression. For me, coming from non-ebikes, my first year on the Vado SL I used assist as sparingly as I could. Developed a rule of thumb, on the level I'd ride unassisted and only use assist once the ride felt sluggish. Then as I got used to the bike occasionally I'd do a quick hilly 15 to 20 miler and just leave assist on Sport (usually something like 70/100) What was interesting is I found my legs were just as tired with this additional assist as they were when I used a lot less assist. I was going faster and - due to the carrot effect - was pushing it more. I'm more easygoing nowadays, sometimes use very little assist for the hell of it, other days stick it in Sport and just enjoy the ride. It's all good!

 

[Jeremy McCreary]

That's a very good expression. For me, coming from non-ebikes, my first year on the Vado SL I used assist as sparingly as I could. Developed a rule of thumb, on the level I'd ride unassisted and only use assist once the ride felt sluggish. Then as I got used to the bike occasionally I'd do a quick hilly 15 to 20 miler and just leave assist on Sport (usually something like 70/100) What was interesting is I found my legs were just as tired with this additional assist as they were when I used a lot less assist. I was going faster and - due to the carrot effect - was pushing it more. I'm more easygoing nowadays, sometimes use very little assist for the hell of it, other days stick it in Sport and just enjoy the ride. It's all good!

Ha, you sound like me! My first ebike— a fairly heavy torque-sensing hub-drive — came after 25 years of very little cycling. Once I got the gearing dialed in for local hills, as you've done, I fell into a silly rule: Lowest possible assist at all times, including the hills. And with 9 assist levels, that 1/9 is pretty low.

In retrospect, that silly rule's the only reason I can enjoy the same hills on a lower-power SL today.

Also like you, I've relaxed the rule over time, but higher-than-necessary assist levels still feel like a guilty pleasure. My SL is set to start in SPORT, and yesterday, I just left it there for the first time. What fun! Guilty pleasures are the best kind.

 

[fooferdoggie]

I debated on posting about that. I think it's because it feels easier to pedal. if I turn up the level of assist when I am tired, I actually have a higher overall wattage output, though my HR is not as high. on my first bosch-powered e-bike with thinner tires, I found I put out a fair amount more watts, and my HR is higher because the bike feels so zippy compared to the fatter tire trek. though with better tires and such, the trek is much better now. but I do tend to put more watts out at higher assist levels, but I don't have as high of a hr, I am not sure why maybe you don't have to exert yourself as much starting out.

 

[Roamers]

Question: Do you sometimes notice a tendency to exert yourself more at higher assist levels?

Aside from playing with assist levels when bikes were new, I've only used highest level once.

First ride of the year, went too far (legs were done), had several miles to go, needed a bathroom badly. Went to full assist, highest gear, don't recall actual cadence ~50 or so (usual cadence is 80-90), basically ghost pedaled at 20 mph.

 

[JGcycle]

I have, on occasion, bumped the assist up to full, when in a hurry to get home. On these occasions, I have noticed myself getting caught up in the moment, and peddling like crazy to keep the speed rush going. It is one big and shiny carrot.

 

[Stefan Mikes]

Yes, your observation is correct Jeremy. Once I am in Turbo, I pedal with all my might to get close to the 45 km/h limit of my Vado 6.0
On the contrary, I pedal rather lazily at the low assistance levels. Today, I rode to a lunch bar. On the way back, I decided I would be pedalling really hard. I was absolutely shocked how fast my Vado would ride at 20/50% assistance (it is 40/100 for a Vado SL) if I really tried!

 

[Jeremy McCreary]

I have, on occasion, bumped the assist up to full, when in a hurry to get home. On these occasions, I have noticed myself getting caught up in the moment, and peddling like crazy to keep the speed rush going. It is one big and shiny carrot.

Exactly. The need for speed has to play a big role in the Carrot Effect. Everyone enjoys a little speed now and then (to a point), and only one way to get the most — pedal hard at high assist. Which rewards exactly the behavior the Carrot Effect promotes.

But I think a sense of "earned speed" also plays a role. I remember this feeling from my roadie days decades ago. Sure, the motor's helping. But in Ground Effect, I'm also making a decent contribution. And that seems to make the speed even more rewarding.

 

[fooferdoggie]

I have, on occasion, bumped the assist up to full, when in a hurry to get home. On these occasions, I have noticed myself getting caught up in the moment, and peddling like crazy to keep the speed rush going. It is one big and shiny carrot.

I do, too, when I am in a hurry for an appointment, and it does not matter what level of assistance, I still work much harder. I had a stress test once and I was late. I actually worked far harder getting to it than I did taking the test.

 

[Chargeride]

I do exactly this, climbing a long hill, I pit it in eco and resign myself to a slow climb, bang it into high and I want the top as fast as possible, and once Ive started I have to finish because I fear my exertion has emptied the tank and slowing down will hurt just the same.

 

[Jeremy McCreary]

...but I do tend to put more watts out at higher assist levels, but I don't have as high of a hr, I am not sure why maybe you don't have to exert yourself as much starting out.

Higher leg power at lower heart rate is a pretty interesting observation. When this happens, could you be pedaling at a more efficient cadence than usual? That is, more efficient for your body, not necessarily for the bike.

You may be onto something with the acceleration angle. Will have to think about it.

 

[fooferdoggie]

Higher leg power at lower heart rate is a pretty interesting observation. When this happens, could you be pedaling at a more efficient cadence than usual? That is, more efficient for your body, not necessarily for the bike.

You may be onto something with the acceleration angle. Will have to think about it.

no cadence is pretty much the same. but I have ridden this route so many times with two different bikes, so it's easy to see it. Plus, I found sweet spots where I use less or more batteries because of my overall wattage output. a little lower or a little higher would give me more range than in the middle of the range I was able to do.
I could only do this because I do this ride so many times. I wanted to try 1" tires on the trek and see how zippy it really is, but I don't want to have to buy new tires since it is 650b rims, and there are a few 1" tires for that size. also, my other bike putting tubless fast wheels would be great, see how it does, but again, I don't really ride it, so it's not worth it. Plus, my other bike is pretty harsh to ride compared to the trek, and I want to s even with a half-decent air fork.

 

[BlackHand]

Yes, absolutely. I used to use custom assist modes to minimize assist on my commute. After my commute became more time bound (drop off and pick up kids on both ends of the day), I had to ramp up assist or give up biking. Now I just commute at higher assist most days and get there faster. I find that I generally put out more watts this way, so probably about the same total work by me. Interestingly, the battery % usage is nearly identical whether I use Tour, Sport, or even Turbo.

If I forgot to charge the bike and have to use Eco on the way in I can save some battery, but only by carefully limiting my speed (and therefore my effort). The number of stoplights I hit has a far greater impact on the battery usage than what assist level the bike is in - full stops and then accelerations from 0 are range killers.

 

[fooferdoggie]

Yes, absolutely. I used to use custom assist modes to minimize assist on my commute. After my commute became more time bound (drop off and pick up kids on both ends of the day), I had to ramp up assist or give up biking. Now I just commute at higher assist most days and get there faster. I find that I generally put out more watts this way, so probably about the same total work by me. Interestingly, the battery % usage is nearly identical whether I use Tour, Sport, or even Turbo.

If I forgot to charge the bike and have to use Eco on the way in I can save some battery, but only by carefully limiting my speed (and therefore my effort). The number of stoplights I hit has a far greater impact on the battery usage than what assist level the bike is in - full stops and then accelerations from 0 are range killers.

yep, I have found that too. on our bosch-powered tandem, though not so much. today we used sport, and I worked a fair amount but I see more battery usage on the tandem then on the trek. on the tandm seldom, do i get the same average wattage output or heart rate, but I burn more calories.

 

[BlackHand]

Higher leg power at lower heart rate is a pretty interesting observation. When this happens, could you be pedaling at a more efficient cadence than usual? That is, more efficient for your body, not necessarily for the bike.

You may be onto something with the acceleration angle. Will have to think about it.

I think cadence can have something to do with it, but it's more to do with bursts of power often needed for acceleration and how the assist can mitigate our bodies' need to recover. It's easier to sustain than it is to attain.

An example where cadence plays into it: my Haibike came with a 50t equivalent chainring. The older motor starts decreasing assist at about 26.5mph and you're at 0 assist by 28mph, but the motor has had noticably increased internal drag this past year and I struggled to hold higher speeds and rarely got into my 11t gear.

In the spring I replaced the chainring with a 45t equivalent. Now I really enjoy a few sections of road I commute on where I hit my power/cadence sweet spot right when the motor is ramping down assist. It's fun to see how long I can hold 250-350w and hold the bike at it's cutoff speed.

The new N+1 seems like it will be great for spirited rides ride at the cutoff, but still sorting things out with it.

 

[Stefan Mikes]

I have now recalled a situation where the ‘carrot effect’ is most pronounced, at least for me! It's a long summer ride when I'm feeling lazy and lacking motivation; and a roadie overtakes me If I can afford it in terms of battery, I turn on the Turbo and start pedalling as hard as if I were racing! I then follow the road cyclist until he gives up I pull up to him, riding two abreast, and start a cheerful, friendly chat with my ‘competitor’, praising his performance and thanking him for giving me a good workout during this boring ride The road cyclist often pulls the earplugs out of his ears and we chat amiably for a while, then I let him go.

Sometimes the road cyclist is not very good and I have no other chance than to overtake him; I usually wish him a good workout as I pass him. We're talking about the ‘carrot effect’ now, so I'll just say that I once managed to overtake a random road cyclist on my Vado SL (unlimited) and gained two minutes on a long stretch of road. Then I noticed an MTB cyclist repairing his bike at a bus stop shelter, so I stopped and offered to help. Two minutes later the road cyclist caught up with me and said admiringly: ‘How great is that bike of yours!’.

Whenever that happens, I pedal at high assist harder than I do on a normal ride!

 

[Chargeride]

The psychology of the terrain is another factor for me, I can tootle up tight switchbacks all day on a mountain, but if you gave me the same climb in a long straight road to the top I'd be switching to high to get it over with.

That is one of the reasons I don't road cycle much these days, I find myself longing for the distant bend rather than enjoying the ride.

 

[6zfshdb]

Not sure if this is your "carrot effect" or not, but I find I exert myself more when using cruise control than PAS. You would think it would be just the opposite, but psychologically, I feel the need to help the bike rather than having it help me using PAS. Maybe it's just me, but I feel a bit guilty using cruise and apply more pedal effort to compensate. As well as getting more exercise, I get significantly more battery range as well. Go figure.

 

[Prairie Dog]

The psychology of the terrain is another factor for me, I can tootle up tight switchbacks all day on a mountain, but if you gave me the same climb in a long straight road to the top I'd be switching to high to get it over with.

That is one of the reasons I don't road cycle much these days, I find myself longing for the distant bend rather than enjoying the ride.

To be quite frank, I enjoy both disciplines and find that they complement each other and that could be the dangling carrot for me. I get as much an adrenaline rush standing on the pedals of my road bike as I do when climbing technical rooty/rocky terrain on my emtb. Same goes for descending. I mainly ride for recreation and can’t be bothered by roadies who look down on their filthy MTB brethren.

 

[leifg]

Perhaps carrot effect is an SL phenomenon -- I have a vado 5.0, and generally just match the assist to the speed I want. It's easy to hit >25mph, so no need to try harder for the carrot (I'm happy with that speed).

Although I do ride much harder when I have assist off! This would be when I want a workout and want to ride 12-15mph, as any assist + high effort for workout would be too fast for where I ride. But when I'm commuting to work, I'm in turbo for speed without sweating.

I also wonder if gearing plays a role with carrot. I have an IGH, and I generally don't change cadence unless I'm climbing a hill, so I don't need to pedal into a cadence if I were being a bit lazy with gear shifting.

While I never had manual shifting with ebike...I would imagine some people may get complacent and rely on motor instead of shifting gears to maintain cadence & effort from start...in which case pedaling harder without shifting gears would push one into a more efficient, faster cadence with the reward of speed.