50 MPH E-Bike Tuck Rule

[st35326]

During my commute I hit a 3-4 mile straight stretch of 50 mph canyon road that is narrow and without bike lanes. Ive found it to be much safer to simply maintain a 50-55 mph rate of speed and "own the lane" rather than have cars go around me, going left of center in doing so (been doing this weekdaily for 2 years). I am able to pedal at a very high rate due to my gearing but from what I can tell from my Cycle Analyst I'm only contributing maybe 100w at a high effort. Meanwhile the motor usually pulls about 4.7kW at this speed.

My question is, at what speed is it better to simply tuck into a more aerodynamic form vs. pedal contribution.

 

[MrDude_1]

I come from a motorcycle background... but..

1. own your lane. You got that right, dont let them think you are letting them by. not at that speed.
2. Never tuck. You are not racing. You want to keep you head up and alert, and your body positioned incase you have to move quickly.
3. You're not adding any power. For you to be able to add power at that speed, you would need to have a front sprocket the size of a large pizza. :lol:

Just ride it like you're a motorcycle until you're ready for them to pass...

 

[wesnewell]

I'd say at any speed above 20 mph. Wind resistance is the strongest opposing force at any speed above ~20 mph. At speeds above 50mph. you could add 10-15 mph by being as aerodynamic as possible. 100W is nothing at high speeds. You'll gain a lot more than that in a tight tuck. Probably closer to 1000W.

 

[st35326]

I come from a motorcycle background... but..

1. own your lane. You got that right, dont let them think you are letting them by. not at that speed.
2. Never tuck. You are not racing. You want to keep you head up and alert, and your body positioned incase you have to move quickly.
3. You're not adding any power. For you to be able to add power at that speed, you would need to have a front sprocket the size of a large pizza. :lol:

Just ride it like you're a motorcycle until you're ready for them to pass...

Good info, thank you. I definitely feel safer not being overtaken, especially when the speed difference between me and a car has the possibility of being so high.

 

[st35326]

I'd say at any speed above 20 mph. Wind resistance is the strongest opposing force at any speed above ~20 mph. At speeds above 50mph. you could add 10-15 mph by being as aerodynamic as possible. 100W is nothing at high speeds. You'll gain a lot more than that in a tight tuck. Probably closer to 1000W.

That makes sense, as 20 mph seems to be when you first start hearing actual wind noise in your ears. Thank you

 

[liveforphysics]

When traveling at higher speeds, tucking makes a tremendous difference in the power required to sustain the speed. I personally tuck everything over say 40mph on bicycles and over 70mph on motorcycles.

 

[dogman dan]

I agree with everybody some. Above 20 mph, your upright chest is causing crazy wind drag.

But I'd rather use more battery, than ever tuck so deep you can't really see ahead. And a deep tuck with your neck cranked so your head tilts up is really uncomfortable. fine for a min, but not for a half hour or more. Not at my age.

Do own the lane, but tuck no deeper than you can do and still see fine. Don't go to a peloton tuck, where all you can see is a wheel 2 feet in front of you. You aren't doing peloton riding, so look up enough to see at all times.

As for the pedaling, even if your gears are that big, above 35 mph your pedaling is just throwing off your balance, and its better to tuck some than try to pedal. I seriously doubt you push hard enough to even get the 100w. You will be using up 100w of energy flapping your legs though. My bikes are geared lower, (52-14) so I stop pedaling at 25 mph. The bike with 20" rear wheel even worse. Useless to pedal it above 22 mph, and it has 56-14. BTW,, 56-11 could pedal to at least 35 mph, then you felt the pedal pressure drop to nothing by 40-50 mph.

 

[bnoooogers]

I believe this is the appropriate position:
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