Why does it feel like The Tandem is more work than my regular bike?

[fooferdoggie]

Now Both bikes are e bikes with bosch mid drives. The motors are the same they both have the same watts and torque but my regular bike tops out at 28 and the tandem at about 19mph.
They both have the same saddle or close enough to not matter. Same distance from the saddle to the bars. Bars are a little higher though on the tandem. Same crank arm length same peddles
Now that I have the computer that shows how many watts I am doing on both bikes I can see what's going on. On a good day on my commute of 10 miles each way I can do 170 to 200 watts average with my heart rate at around 135. On longer rides on my regular bike I may average 150 or so watts for 2.5 Horus and 40 miles with my heart rate around 130 average.
Now I have not taken a longer ride yet on the tandem now that I have the meter but the shorter rides 10 to 25 miles. But the average watts is 90 or so with 150 feeling fairly hard for me. My wife can peddle with me holding my legs still and the motor shows no watts. It is freewheeling when she is putting more effort into than me. She is driving the bike but not effecting the watt meter. I am sure she is taking watts away with her effort.
Also I keep 80 rpm cadense on my regular bike or a bit higher but its harder to keep that cadence on the tandem. It feels like I am putting more watts out then I am but my heart rate reflects how many watts I am putting out fairly well. It is around 110 to 115
The average speed is higher on my regular bike I like to cruise around 22mph but o the tandem we cruise right at the point the motor is hardy using any watts around 18.5.

 

[Comfortably Numb]

Now Both bikes are e bikes with bosch mid drives. The motors are the same they both have the same watts and torque but my regular bike tops out at 28 and the tandem at about 19mph.
They both have the same saddle or close enough to not matter. Same distance from the saddle to the bars. Bars are a little higher though on the tandem. Same crank arm length same peddles
Now that I have the computer that shows how many watts I am doing on both bikes I can see what's going on. On a good day on my commute of 10 miles each way I can do 170 to 200 watts average with my heart rate at around 135. On longer rides on my regular bike I may average 150 or so watts for 2.5 Horus and 40 miles with my heart rate around 130 average.
Now I have not taken a longer ride yet on the tandem now that I have the meter but the shorter rides 10 to 25 miles. But the average watts is 90 or so with 150 feeling fairly hard for me. My wife can peddle with me holding my legs still and the motor shows no watts. It is freewheeling when she is putting more effort into than me. She is driving the bike but not effecting the watt meter. I am sure she is taking watts away with her effort.
Also I keep 80 rpm cadense on my regular bike or a bit higher but its harder to keep that cadence on the tandem. It feels like I am putting more watts out then I am but my heart rate reflects how many watts I am putting out fairly well. It is around 110 to 115
The average speed is higher on my regular bike I like to cruise around 22mph but o the tandem we cruise right at the point the motor is hardy using any watts around 18.5.
View attachment 88676View attachment 88677

Maybe try painting it red. CN

 

[reed scott]

Because your partner is ghost pedaling.

 

[fooferdoggie]

Because your partner is ghost pedaling.

no the watts show how much I am doing regardless of what she is doing. but she is not I can see her heart rate. but my regular bike is designed for speed and the tandem is designed more as a cruiser. though I have changed it enough to make it more of a all around riding bike.

 

[alphacarina]

The tandem is designed to deal with twice as much weight, but is powered by the same motor. The gearing is probably a little different which could account for the difference in the top speed. The bike frame probably weighs about double too, made of heavier gauge stuff to deal with the extra weight

Stay safe on it! - You've had a couple serious tumbles already - I'm kinda surprised your wife is still willing. Maybe time to look at a tandem trike?

Don

 

[soyabean]

The tandem is designed to deal with twice as much weight, but is powered by the same motor.

The OP thinks two humans can produce double the power, but forgets there is no double on the motors...

Consider those tourist pedal cars where 4 humans are pedalling. Even if it had one 250w motor, it may as well not even exist as the best it could do is replace only 1 of the 4 humans.

 

[fooferdoggie]

The OP thinks two humans can produce double the power, but forgets there is no double on the motors...

Consider those tourist pedal cars where 4 humans are pedalling. Even if it had one 250w motor, it may as well not even exist as the best it could do is replace only 1 of the 4 humans.

no you did not read what I said. I said it feels like I am putting out say 170 watts but I am only putting out say 120 watts. I said it feels like I am working hard but I am not my heart rate is lower and I am putting out less watts then it feels like I am. I also have trouble keeping my cadence as high as I can on my regular bike. I can do a 30 mile ride on my regular bike average 150 watts with a heart rate of 135. on the tandem with the same effort well it feels the same I am doing maybe 120 watts with a heart rate of 110 to 115.I may be able to keep it at 150 for a bit bit it feels harder then it does on my regular bike where I am putting out more power.

 

[fooferdoggie]

The tandem is designed to deal with twice as much weight, but is powered by the same motor. The gearing is probably a little different which could account for the difference in the top speed. The bike frame probably weighs about double too, made of heavier gauge stuff to deal with the extra weight

Stay safe on it! - You've had a couple serious tumbles already - I'm kinda surprised your wife is still willing. Maybe time to look at a tandem trike?

Don

no we fell over once. well twice one on a trail the front wheel slid out and we fell over. thats just learning curve. only one good crash and really the only rash I have had in the 25,000 miles of biking. a trike would be cool but they are way too expensive and would not work in the city =the Yahveh a way to big of a turning radius.

 

[soyabean]

Now Both bikes are e bikes with bosch mid drives. The motors are the same they both have the same watts and torque

How can you expect the same motor to move something that is 200% bigger in everything??

 

[fooferdoggie]

How can you expect the same motor to move something that is 200% bigger in everything??

you still don't get it. I am not saying anything about the power. I keep telling you it feels like I am working harder then I am. it has nothing to do with anything on the motor. I am not saying we are going slow. I am saying it feels like I am working harder then I actually am. I am trying to figure out why it feels harder to put the same effort into the tandem then I can on my bike. why is it I can put out 170 watts myself on my regular bike and have a heart rate of 130 and on the tandem I am only putting out 120 watts or so and a heart rate of 110 but it feels like the same effort. do you get that????
I never said why are we going slower why is it more work. I said why does it feel like more work but actually is not.

 

[soyabean]

I keep telling you it feels like I am working harder then I am. it has nothing to do with anything on the motor.

What's the solution you are looking for?

There is nothing mechanically wrong with the ebike, and it's unfeasable to double-up with a second motor.

Maybe time to look at a tandem trike?

Agreed. One of those beefy cargo bikes with a long frame, lots of watts and lots of Ah.

 

[Comfortably Numb]

What's the solution you are looking for?

There is nothing mechanically wrong with the ebike, and it's unfeasable to double-up with a second motor.


Agreed. One of those beefy cargo bikes with a long frame, lots of watts and lots of Ah.

fooferdoggie......I guess you'll have to try explaining it a third time.
CN

 

[RunForTheHills]

It seems like you are in a more aggressive riding position on the regular bike. The handlebars are higher and the seat is set further back from the pedals on the tandem so you are not getting as much of your weight over the pedals as you are with your regular bike. It might be worth paying for a bike fitting at your LBS if you have one near you that offers that service.

 

[fooferdoggie]

It seems like you are in a more aggressive riding position on the regular bike. The handlebars are higher and the seat is set further back from the pedals on the tandem so you are not getting as much of your weight over the pedals as you are with your regular bike. It might be worth paying for a bike fitting at your LBS if you have one near you that offers that service.

thats what I am thinking. but I don't want to lower the bars its good to not be in the same position for longer rides a little ore upright saves my hands and arms. I know I cant spin as fast on it. I thought the crank arms may have been different but they are the same. its not a big deal. we went up a steep road we go up a lot and I go up a lot too it takes me about 350 to 400 watts to get up if I am in tour. it took about 300 watts in turbo for both of us. I think thats about what I get on my regular bike or close to it. the tandem was setup as a cruiser too we have changed it but it is still more of a basic bike. my bike is setup as a fast commuter/tour bike.

 

[fooferdoggie]

fooferdoggie......I guess you'll have to try explaining it a third time.
CN

would it help? or is it like the Porsche e bike your just not gonna get it?

 

[theemartymac]

I would second the riding position as one likely culprit. The forward lean on a more aggressive bike not only improves the aerodynamics, but lets you exert more force with each stroke as your weight is right over the downstroke pedal. I also can't say for certain, but there will likely be slightly higher power losses in a drivetrain of that length, so every ounce of power you apply will not make it to the rear wheel intact. Can't say how much, but if it's 10%, that would be noticeable?

Another thing to consider is that despite the bikes increased weight, it won't be anywhere near double the weight of a standard version. So in tandem you are actually pedaling LESS than half a normal bike. The Pedego beach cruiser for example is 50lbs no battery. The tandem version of the same bike is still only 70lbs. The fact that there is only one motor and battery, and two tires not four means you cut a lot of duplicate weight. And no one uses 100% motor output for very long if at all, so you don't need the second motor to make up for it. Typically we cruise with much less than 50% assist, only spiking the output for starts and hills, so your motor has the reserve capacity to help the bike perform very similarly for most of your ride.

From the very little I have heard about tandems, only knowing a few serious tandem riders/racers over the years, the key is getting both riders in sync over time (power output, timing, and fitness). Until that bond is developed, there will be increased efficiency losses due to the minor differences in individual technique. Once the pair are truly used to each other and riding in sync, it should be easy to blow a solo normal rider out of the water so to speak.

 

[fooferdoggie]

I would second the riding position as one likely culprit. The forward lean on a more aggressive bike not only improves the aerodynamics, but lets you exert more force with each stroke as your weight is right over the downstroke pedal. I also can't say for certain, but there will likely be slightly higher power losses in a drivetrain of that length, so every ounce of power you apply will not make it to the rear wheel intact. Can't say how much, but if it's 10%, that would be noticeable?

Another thing to consider is that despite the bikes increased weight, it won't be anywhere near double the weight of a standard version. So in tandem you are actually pedaling LESS than half a normal bike. The Pedego beach cruiser for example is 50lbs no battery. The tandem version of the same bike is still only 70lbs. The fact that there is only one motor and battery, and two tires not four means you cut a lot of duplicate weight. And no one uses 100% motor output for very long if at all, so you don't need the second motor to make up for it. Typically we cruise with much less than 50% assist, only spiking the output for starts and hills, so your motor has the reserve capacity to help the bike perform very similarly for most of your ride.

From the very little I have heard about tandems, only knowing a few serious tandem riders/racers over the years, the key is getting both riders in sync over time (power output, timing, and fitness). Until that bond is developed, there will be increased efficiency losses due to the minor differences in individual technique. Once the pair are truly used to each other and riding in sync, it should be easy to blow a solo normal rider out of the water so to speak.

ya the bikes geometry is not for racing. it is 65 pounds with nothing but the battery. but it also has 1.75 tires verses 1.5. the cadence thing is the biggest hint. I can spin at 90 on my regular bike but 85 is a struggle on the tandem. its not really a big deal and I ride so mun=ch I may be better off not working as hard as I do on my regular bike. I will getting 30 or miles a day now that the weather is improving.

 

[fooferdoggie]

Now I can measure my watts I can put the same amount out on either bike climbing steep hills. I got 400 watts climbing the steep little section of path. It would be cool to know how many watts my wife puts out. But our average watts really sucks this last ride was 25 miles and we only averaged 69 watts. We used less battery then usual too. For once Strava had a higher wattage then what I actually did usually Its lower.