Regenerative braking


Bionicman

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I'd like to start a discussion regarding the vehicle effects during cornering.


As I have entered a corner very fast that required braking in addition to the full regenerative braking effect. While I would need some additional testing to confirm. Perhaps some of the motocross guys can provide input?
Regardless it proved very hard to set corner entry/mid corner speed due to the differing levels of braking received from the bike. It was as if once the rear brake was applied all regenerative braking released thus requiring the rear brake to compensate for the level of deceleration of previous? Then releasing the rear brake application the regenerative braking effect returned until throttle application of corner exit?
This all let in a less than linear cornering entry/mid/exit speeds with missed lines as a result & certain distrust in the level of feedback regarding sticking the line of intention.

Thoughts?
 

snydes

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Well there would be no electrical connection on the mx bikes that would be able to indicate to the bike that brakes were applied that could trigger anything as far as regen braking, so that couldn’t be a thing.

I suppose on an ex/r or sm something like that could be possible.
 

leeo45

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So you are saying that the regen cuts off when you apply the rear brake, or at least it feels like that is what happens? I haven't noticed anything like that on my EXR. I have ridden the bike fast on single track, however I haven't had it in a true race situation yet. My enduro race race bike is a 4-stroke KTM with an auto clutch and the regen seems very similar to the 4 stroke engine braking. The Rekluse clutch doesn't disengage unless the rear wheel locks completely. If it will ever quit raining I'll go do some experimenting and report back.
 

Bionicman

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Think corner entry - lock up rear tire/brake to ‘back in’ the bike to point in exit direction

Felt when rear tire was momentarily locked bike actually sped up due to the expected braking combination released??
 

querlenker

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It may be possible that the inverter does have an anti wheel lock function. When during regen braking the rear wheel lock while rear brake is applied too, it could stop regen. I know this from other motor controllers, so maybe Alta has the same. Alta experts should know if this is the case
 

Bionicman

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Full respect Fog but not going to get into a riding technique discussion - simply asking if this phenomenon has been an issue to the other small circle of Alta owners
 

TCMB371

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I'm pretty sure the regen fades away near 0 RPM. In fact, it likely is beginning to fade away at low rpms (like 3-4000rpms). And it likely fades in over a short time so that you don't abruptly get a regen effect when the wheel begins to spin again without throttle input.

In terms of feeling those effects, i can't say i've pinpointed what you are describing. I usually back into corners like you do (rear end locked up) and am applying throttle before i let off the rear brake. However, i would prefer if the bike freewheeled a bit more.
 

Philip

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Regen is speed sensitive. Can't have regen if the rear wheel is locked, right?

Are you having trouble keeping the rear wheel locked with a LHRB or your rear brake, or is it about the smoothness of the braking to power sliding transition?
 

Bionicman

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WA
my issue with the phenomenon is
1 lack of confidence in knowing how the motorcycle will behave in certain conditions
2 yes the linear speed adjustments requested from the rider should be consistent & exact

I guess at the end of the day this can not be tuned (just trying to technically understand) so I should just grow a pair & ride...
 

Bionicman

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I'm pretty sure the regen fades away near 0 RPM. In fact, it likely is beginning to fade away at low rpms (like 3-4000rpms). And it likely fades in over a short time so that you don't abruptly get a regen effect when the wheel begins to spin again without throttle input.

In terms of feeling those effects, i can't say i've pinpointed what you are describing. I usually back into corners like you do (rear end locked up) and am applying throttle before i let off the rear brake. However, i would prefer if the bike freewheeled a bit more.

I would concur with this notion that the regen effect changes depending on speed/rpm?
 
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