Since you seem so sure of that, can you tell me how your rear tire is moving laterally to rotate around the COM? Lots of skidding? Some kind of rear steering?
Why don't you pedal your ebike?
- Thread starter ebike4healthandfitness
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Most single-track-vehicles do NOT "lean" while in motion. Trees lean, fence posts lean, but not bikes.
As with aircraft, the bike's CoM ROTATES, centered along the vehicle's longitudinal roll axis.
The "rotating" is initiated by laterally repositioning the front tire's contact patch beneath the vehicle's CoM.
On a typical street motorcycle, the longitudinal roll axis runs diagonally from at or near the head tube region, to at or near the rear tire's contact patch.
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Not always.
There is no CoM 'sweet spot'. Bikes with low COM (at or below the axles) increases steering input resistance, and reduces sensitivity. Great when riding a Harley or GoldWing at speed while touring, but becomes a frustrating handful when navigating city street at 25mph.
Dirt bikes, at the other extreme, typically position the CoM much higher, which reduces steering input resistance, increases steering sensitivity and makes balancing easier. Preferred attributes at lower speeds and switchback trails.
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Hummina Shadeeba
10 MW
There’s a lot of complications and a lot of possible practical goals but where would mass be best positioned solely to get through a tight serpentine course the fastest?
ebike4healthandfitness
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The yaw angle doesn't get that big in normal riding:
Roll, Pitch and Yaw | DRAWING THE LINE
An airplane rotates around its three CG-intersecting axes. How does it work with bikes?
www.motorcyclistonline.com
hillslayer@
100 W
Most of my riding is high speed rural roads stability rules, my effective headtube angle is 66 degrees. Slow tight turns can be a little tricky.
ebike4healthandfitness
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All normal turning involves leaning.
Oh, and I already knew (prior to post #80 of this thread) bikes roll around their center of gravity and not around a line connecting their tire footprints:
Do you use an fairing or partial fairing on your ebike, emoped or BSM?
Chalo wrote: "Low center of mass impairs both maneuverability and control, because... " And he explained why.
endless-sphere.com
"Why? Engineers had imagined that as a bike rolls in changing direction it is pivoting on a line through its two tire footprints. If that were true, putting the fuel on the bottom would make it easier to pivot because it would be swinging through a shorter arc than if it were up on top of the engine, farther from the ground.
But that’s not what happens. At one track I could stand and watch bikes coming straight toward me, then turning right. In light rain I could see the trace of their travel as a line on the track. As the riders countersteered to their left to make their bikes flick to the right, the tire footprints moved to the left as the tops of the bikes tilted to the right: They were rolling, not around a line connecting the tire footprints, but around the center of gravity of bike, fuel, and rider, which is about 22 inches off the pavement. They were pivoting around their roll axes."
Before I linked that article people were thinking this:
Do you use an fairing or partial fairing on your ebike, emoped or BSM?
Do you think you're losing a lot in the conversion, or is the panel just not putting out much more than 15W? Both! Hard to say as I've never hooked it up to a proper MPPT to verify, but I suspect my DC-DC is only 80% efficient at best. The panel is '40W' by Chinese standards, so really probably...
endless-sphere.com
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Only the ignorant bystander observing a biker negotiating a corner, sees it "leaning",... completely oblivious to the dynamics at play. Maybe this will help....
dictionary.cambridge.org/us/dictionary/english/lean.
"to (cause to) slope in one direction, or to move the top part of the body in a particular direction:"
I'm done here.
ebike4healthandfitness
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That definition has nothing to do with where the pivot point is.
For example, that same dictionary (Cambridge) defines an aircraft rolling (which even you used in post #77) as also leaning:
roll
1. to (cause something to) move somewhere by turning over and over or from side…
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tomjasz
1 GW
My rides are all now one speed. No reason on flat streets for the nuisance of gearing. KISS
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