best way to improve handling?

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where's the best place to put the battery when all life on the the ebike is imagined as a supermoto race?

is the axis of rotation between the center of the headtube and bottom of the rear wheel? should i shoot for all the weight as close within that line to reduce moment of inertia? what are the variables?

last bike i made i put the weight as low to the ground as possible in a misguided understanding that lowering the weight was always best. in what situation would lowered COM be best?

"handling" is a broad term. what of "turnability", 'stability" "?"...
 
Hummina Shadeeba said:
"handling" is a broad term. what of "turnability", 'stability" "?"...
Good that you recognized the variability and ambiguity in the term "handling."
Recall the ES thread about footpegs vs. pedals? Contentious!

Practically, I tend to take cues from motorcycle design. If you ride mostly offroad, emulate the weight concentrations found on a MX motocross bike. If you ride slowly over daunting obstacles, mimic the design of a trials bike. If you ride hi-speed road, look at how the heavy components are laid out on a GP formula bike.

You are correct, lower (lowest?) is not always better. Remember the experimental GP bike where they switched gastank/exhaust pipe locations, placing the heavy fuel down low? Handled poorly and was quickly abandoned.
 
Copy it. The geometry. What do you want? Exactly?

Copy they style of geometry you want. Easy. They have been building two wheeled vehicles for long time now. The designers know what you need. For any specific setup of suspension geometry vs applications.

Look at the differences between a typical bicycle geometry ( downhill, XC, ect... ) vs the geometry of a modern supermoto bike.

So you want a "dirt bike with street tires?" ? ... Supermotoo like handling? Round 3.5", 90mm trail? Plush suspension to handle the lower speed cornering ( no scraping pegs.. er pedals..... like a sport bike ).. but setup for a little less travel ( on road,.. ) and a harder spring ( on road you go faster than off road) ( and you dont need that super long travel and plushness to not bottom out on the face of a jump anymore, onroad...) ... But still comfy to ride? Little more weight on the front wheel than a typical dirt bike, maybe? Static ( dead, not live ) loaded of course. Strong enough front forks to resist a dive. Sag to right where your feet hit the ground ( high for a race streetbike... ) ( dont build it to high) ( the highsides suck).. and short ( not long like a sport bike)..

The more tire you have ( width ) the faster you can go around turns, A nice wide front tire.

The absolute best place for a battery? I would say low, right under the rider, above the cranks, in the center of the bike if you can.

Not a supersport lean in, and or handling, nor a full blown off road bike... but kinda in between? Lean "on",,, staying slightly upright? Where will you ride it most? A light, flickable dirt bike seating position ( put your foot down bike ) that is good for (designed around) typical road courses you may encounter ( such as public roads, tracks, or parks? Urban? Rural? ) ..


Then build/buy hardware to suit.
 
Footpegs vs pedals thread was interesting to begin with and now, with the ability to put the battery anywhere Id like to fine tune to what would be understood “best”, at least for a tight city urban commuter. It’s a mountain bike frame 26” wheels with 70 deg headtube. motor goes in the center hole, which is also nicely in-line between the rear wheel patch and center of headtube. Reducing moment of inertia I think. I’m over simplifying “handling” with that one goal. Why not?
 

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Best way to improve handling, is saddle time. Could be some nuances between even an inch difference in heavy, bulky battery placement.
 
I make a mold for the battery so I can’t adjust and try different positions if that’s what you mean.

I’m trying to find what different theories related to COM and handling are.

If the lean angle is the same regardless of the COM height, why not go higher? Or is having the weight as close to the axis of rotation better?

If a heavy battery were possibly placed completely within even an inch of the axis of rotation of the bike, would that reduce moment of inertia the most and allow the quickest handling? Is there even an axis of rotation between rear wheel patch n top of the headtube or would any weight above the contact patch be perceived and slow turning the higher it is?
(Forgetting wheelbase and head tube angle)
 
Hummina Shadeeba said:
If a heavy battery were possibly placed completely within even an inch of the axis of rotation of the bike,

The roll axis of the bike is at the height of the bike+rider center of mass and parallel to the ground. So even with a rider of fixed size and weight, its height will change some according to the rider's position.

Locating a heavy battery at this height will enhance the bike's ability to quickly snap into a turn, but it would be difficult to install because in most cases it would be above the bike. Also, at very low speeds or when parking the bike, being so top heavy would become a liability.

Probably the best you can do if this is your objective would be to mount the battery on the top tube in the "gas tank" position. That's fairly close to the bike's dynamic roll axis and also pretty convenient.
 
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