Did tiltback throw me to the ground? 18XL

[Smoother]

1 hour ago, Scatcat said:

So is the 18XL tilt-back really that violent? I remember on my GT16 it was like the swing of a hammock, it was as if the wheel caught you, not any brutal dislodging attempt

I have yet to go fast enough on my MSX to even get close to tilt-back, 38 kph is my max so far. But I really should check it out this weekend.

My preferred method of checking out tilt-back, is to set it to a really slow speed, and then try it out while still not in any real danger. Then I know more what to expect when it happens at speed.

I don't think tilt back severity is related to the speed it is set at as much as it is related to how rapidly you approach tilt back.  If you sneak up on it, at any speed, it has time to get the pedals in front of you.  If you race up to it, it has to also race to get in front of you.  This is the viloent tiltback @Lutalo was referring to.  I have experienced it on both my KS wheels.  It really is, as he said, heart stopping.  Sometimes one is able to stay on and sometimes it dirt sandwich time. PTSD may be an overstatement, but it was funny.  Maybe "gun shy" is a better description.  Once you've had violent tilt back at speed, a few times, you get very gun shy.  I NEVER want to experience it again.

EDIT However I do believe there is a fix for this and it's quite simple.  The firmware monitors your rate of acceleration and calculates the time at this rate, to your tilt back setting, and starts feeding it in at a lower speed, giving you time to recognize the "cliff" you are racing towards, and react calmly.  In theory the tilt back should be able to complete in about the same amount of time, lets say 2 seconds, almost every time.  The only time you would be able to override the 2 seconds would be if you were rolling just under tilt back and suddenly and aggressively leaned into it.  This would not give the algorithm anything to work with. 

The worst of the current scenarios is violent tilt back to cut off.  I think I have experienced this too. Scenario: small battery (340Wh) low charge (under 50%) cruising just under top speed (19mph)  on smooth black top.  Suddenly several ripples in the smooth blacktop causes a power surge to maintain speed, tilt back kicks in as a result of the wheel accelerating over the bumps, followed by a shut off because the BMS (or something) didn't like the high current demanded by the tilt back. My only REAL face plant (bloody chin). 

[Scatcat]

1 hour ago, Smoother said:

I don't think tilt back severity is related to the speed it is set at as much as it is related to how rapidly you approach tilt back.  If you sneak up on it, at any speed, it has time to get the pedals in front of you.  If you race up to it, it has to also race to get in front of you.  This is the viloent tiltback @Lutalo was referring to.  I have experienced it on both my KS wheels.  It really is, as he said, heart stopping.  Sometimes one is able to stay on and sometimes it dirt sandwich time. PTSD may be an overstatement, but it was funny.  Maybe "gun shy" is a better description.  Once you've had violent tilt back at speed, a few times, you get very gun shy.  I NEVER want to experience it again.

EDIT However I do believe there is a fix for this and it's quite simple.  The firmware monitors your rate of acceleration and calculates the time at this rate, to your tilt back setting, and starts feeding it in at a lower speed, giving you time to recognize the "cliff" you are racing towards, and react calmly.  In theory the tilt back should be able to complete in about the same amount of time, lets say 2 seconds, almost every time.  The only time you would be able to override the 2 seconds would be if you were rolling just under tilt back and suddenly and aggressively leaned into it.  This would not give the algorithm anything to work with. 

The worst of the current scenarios is violent tilt back to cut off.  I think I have experienced this too. Scenario: small battery (340Wh) low charge (under 50%) cruising just under top speed (19mph)  on smooth black top.  Suddenly several ripples in the smooth blacktop causes a power surge to maintain speed, tilt back kicks in as a result of the wheel accelerating over the bumps, followed by a shut off because the BMS (or something) didn't like the high current demanded by the tilt back. My only REAL face plant (bloody chin). 

That is actually a brilliant way to deal with the problem. So far I've been lucky. The only time I've had a scary tilt back, was accelerating brutally fast in a curve with a little bit too little charge left in the batteries. My GT16 more or less said, "oh no, you don't!" and started a tilt-back in the middle of my turn.

That was fun! NOT!!! But I stayed on and in control, but with a pulse close to 200.

[Lutalo]

1 hour ago, Smoother said:

PTSD may be an overstatement, but it was funny.  Maybe "gun shy" is a better description.

But, what about the night terrors caused by my recurring dream where a sudden tiltback causes me to fly off the XL, kiss the ground and gift the asphalt my teeth? I wake up panting, and in a cold sweat. 😱😱😱😱😰😰😰😰

[Lutalo]

29 minutes ago, Scatcat said:

EDIT However I do believe there is a fix for this and it's quite simple.  The firmware monitors your rate of acceleration and calculates the time at this rate, to your tilt back setting, and starts feeding it in at a lower speed, giving you time to recognize the "cliff" you are racing towards, and react calmly.  In theory the tilt back should be able to complete in about the same amount of time, lets say 2 seconds, almost every time.  The only time you would be able to override the 2 seconds would be if you were rolling just under tilt back and suddenly and aggressively leaned into it.  This would not give the algorithm anything to work with. 

I like it. Just don't ask me to test it. 

[Smoother]

2 minutes ago, Lutalo said:

I like it. Just don't ask me to test it. 

Go on! Take one for the team.

[Lutalo]

2 hours ago, Smoother said:

Go on! Take one for the team.

Sure, if the team is gonna pay for the teeth implants 👍

[Jens Ronnedal]

I don't think that the tilt-back on the KS18XL is any worse than Inmotion V8. And I haven't ridden any other wheels to compare with yet. But I think that the tilt-back feels more violent the more you lean into it. I'm always aware of my tilt-back settings and battery level. So I rarely or never get tilt-back that I didn't already know was coming.

[Rama Douglas]

Tilt-back to me is much more jarring on the XL than my previous wheel (V5F). Thankfully, I haven't experienced it at top speed. Haven't reached that yet...🤪 But the other day while doing a moderate incline, I was pushing it up the hill at around 23mph, and probably less than 40% battery, and I got the sudden tilt-back. I kept it under control, but yeah, the heart rate certainly spikes! The V5F has a very gentle tilt-back comparatively. Even at the XL's slower speed when tilt-back surprised me at 12mph when the app decided to default to original settings one day, it felt pretty strong. 😬

[Paul2579]

7 hours ago, Scatcat said:

So is the 18XL tilt-back really that violent? 

I don’t know that violent is the correct descriptor.  On my slow speed tests it did put me in an aggressive braking position.  Not violently so, but inevitably so.  In fact, I think the lack of violence may have added to my confusion when I first tripped the threshold by accident. I felt disoriented, rather than pushed around.  If you know it’s coming and go with it to a full hard brake it seems natural enough.  But if I were surprised it again with no warning, I think I would struggle to keep my poise.  

[Scatcat]

6 hours ago, Paul2579 said:

I don’t know that violent is the correct descriptor.  On my slow speed tests it did put me in an aggressive braking position.  Not violently so, but inevitably so.  In fact, I think the lack of violence may have added to my confusion when I first tripped the threshold by accident. I felt disoriented, rather than pushed around.  If you know it’s coming and go with it to a full hard brake it seems natural enough.  But if I were surprised it again with no warning, I think I would struggle to keep my poise.  

You need to experience it a few times. When you have, it is no big drama anymore. Sure doing it like I did in a turn is less than fun, but mostly it has been limited to an "oh, I seem to have been a naughty boy... again..."

Thing is, when you get it, just go with the flow and brake, and then it's nothing.

[Smoother]

On 2/16/2019 at 12:08 AM, Scatcat said:

You need to experience it a few times. When you have, it is no big drama anymore. Sure doing it like I did in a turn is less than fun, but mostly it has been limited to an "oh, I seem to have been a naughty boy... again..."

Thing is, when you get it, just go with the flow and brake, and then it's nothing.

I can't understand this statement.  In my experience of violent tilt back (more than four times), several things conspire to prevent the response you describe:

1. the wheel suddenly shooting out in front, is very shocking and complexity take you by surprise

2. the severe tilt initially puts the front of your ankle under severe compression while your body still thinks it is riding/leaning forward normally)

3. because the wheel has now shot out violently in front of you your weight is suddenly, without your consent, back behind the wheel but the wheel is now travelling faster than it was right before tilt back because the wheel had to accelerate to initiate tilt back

4. trying to brake now (0.5 seconds since the whole episode started, so you have had almost no time to think)) you will find there is nothing to brake against because the backs of the pedals are gone, simply gone.  The tilt back has placed them so low that you physically cant get your heals down with any amount of force without leaning back so far you end up doing a butt plant (with associated straight arms), at a high speed. 

This exact scenario is the only time I have hurt a wrist (with wrist guards on) while EUCing.  Accelerated too hard on small, depleted battery.  Wheel went kamakazi tilt back, I get dumped on my ass/straight arms, wheel shoot out in front 15 metres, I stand up and take a bow to the glass fronted restaurant full of diners watching me, go search for my wheel, ride home, wrist sore for 5 days.

Yes I've survived other full tilts, but the amount of associated arm flapping, sphincter clenching, hear racing stuff is not something I would describe as "no big drama".  That's drama I can live without thank you very much.

[Mono]

Some of this is mitigated by anticipating the tiltback and reacting quickly enough. However, the extreme foot angle can indeed be very problematic. It is difficult to adopt, pushing the heel (which is sometimes necessary) becomes very difficult or even impossible, and it is even easy to slip off the pedal. Still, the main problem I think usually is to be caught by surprise and the lack of experience with the situation.

[Dzlchef]

44 minutes ago, Mono said:

Some of this is mitigated by anticipating the tiltback and reacting quickly enough. However, the extreme foot angle can indeed be very problematic. It is difficult to adopt, pushing the heel (which is sometimes necessary) becomes very difficult or even impossible, and it is even easy to slip off the pedal. Still, the main problem I think usually is to be caught by surprise and the lack of experience with the situation.

Totally agree!  The problem being that one can only do so much practice and must live through many sphincter tightening events to gain the experience needed.  I really don’t look forward to my next but bring it on!

 

[Smoother]

2 minutes ago, Dzlchef said:

Totally agree!  The problem being that one can only do so much practice and must live through many sphincter tightening events to gain the experience needed.  I really don’t look forward to my next but bring it on!

 

Exactly.  How many times do I have to put my body on the line before I become comfortable with my wheel going full blown ninja on me when I don't expect it.  That's one learning curve I'm happy to give a wide berth to.

[Mono]

2 hours ago, Dzlchef said:

Totally agree!  The problem being that one can only do so much practice and must live through many sphincter tightening events to gain the experience needed.  I really don’t look forward to my next but bring it on!

If the tiltback speed is adjustable over the full speed range (as it is on my wheel), one can practice this situation to any desired extend. I am not saying such practice sessions are a lot of fun, I am just saying it's entirely feasible then.