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To me engine brake is amount of deceleration when throttle is closed, I didn’t think there is any engine brake after throttle is opened 1%
Agreed.

An easy test is to accelerate to a given speed; e.g., 60 MPH and pull in the clutch. Note the deceleration. Now do the same without touching the clutch lever and add throttle until the deceleration is the same. It takes just the tiniest touch of fuel to overcome engine braking.

A bit of useful data would be to know the difference in fueling between the S1000RR's engine braking in slick mode v. all other modes.
 

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Can you further explain air drag and engine brake? To me engine brake is amount of deceleration when throttle is closed, I didn’t think there is any engine brake after throttle is opened 1%
You have datalogger, first test rolling resistance and air drag, upright, clutch pulled in.
Then test engine brake, upright, with different speeds, gear, and RPMs.
Or check you current data? There might be spots where you can see those.

And/or measure the throttle valve opening % vs RPM when you slowly apply throttle at stand still.
Can you get max RPM with 1% throttle valve opening...? If not, then you have engine brake.
Too easy/ too difficult to understand?
 

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Agreed.

An easy test is to accelerate to a given speed; e.g., 60 MPH and pull in the clutch. Note the deceleration. Now do the same without touching the clutch lever and add throttle until the deceleration is the same. It takes just the tiniest touch of fuel to overcome engine braking.
Which gear and RPM...?
Which gear and RPM are you using when you are riding on a track at 60 MPH?
 

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Unfortunately, no. The centripetal force which must be produced for a vehicle to corner is substantial. This is the force we are counteracting by leaning the bike. It is the force which is greatly diminished when transversing a banked corner v. no banking. It is equal to the inertial which wants to throw you off of the track, makes your body in a car slide to the outside, makes a car lean hard to the outside.

Consider, as a simile, straight line acceleration. To equal 1g of acceleration, a vehicle needs to run 0-60 MPH in 2.74 seconds. The S1000RR, in the correct hands, is capable of this using its full 199hp. Now consider, a cornering force of 1g. While not directly comparable, it takes considerable energy to drive a vehicle around a corner at 1g. This is because one is continually accelerating in a new direction toward the inside of the corner. This takes a lot of energy.

Again, this is not perceived as a major factor until one is cornering hard - as you should be doing on the track. In a car on a leisurely drive, one does not feel thrown to the outside of a corner. But in a high speed corner taken hard, the forces are pronounced and can be quite violent.

Also, regarding engine braking, engine braking produced by an in-line four is relatively small, even smaller on the S1000RR in slick mode with its increased fuel overrun. The smallest throttle opening cancels engine braking as all is required is sufficient fuel to keep the engine spinning. The bike will quickly slow down regardless - pull in the clutch on a straight away at speed and the bike slows rapidly. Drag is the biggest culprit in slowing the bike in a straight away. Drag and cornering friction are the two biggest in high speed corners.
Can you even make guess how big is the longitudinal vector of the cornering friction for example with; s1k, dunlop slicks, 60mph, when cornering force is 1G?

Have you ever analysed any real life data? Or are you just makeing pure assumptions?
 

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And/or measure the throttle valve opening % vs RPM when you slowly apply throttle at stand still.
Can you get max RPM with 1% throttle valve opening...? If not, then you have engine brake.
Too easy/ too difficult to understand?
Okay I am starting to see where the language difference is causing the confusion.

Finnish engine brake = amount of throttle required to maintain speed / overcome rolling resistance / equal camber thrust

Am I understanding this correctly?
 

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Okay I am starting to see where the language difference is causing the confusion.

Finnish engine brake = amount of throttle required to maintain speed / overcome rolling resistance / equal camber thrust

Am I understanding this correctly?
No.

These are not from data:
Lets say you are driving on 2nd gear and 10 000 rpm, and you pull the clutch, and deceleration is 0.2G.
Then you know that rolling resistance and air drag is 0.2G at that speed.
Then 2nd gear 10krpm, and then twist grip 0%, deceleration is 0.4G.
Then you know that engine brake is 0.2G @ 2nd @ 10k.
Then you check throttle valve % at 2nd 10k.
If it is for example 10%, then you can make a coarse estimation that 5% goes to rolling resistance and air drag, and 5% to engine brake.
But if you want to be sure, then yo must test what is the throttle valve % which gives you 0.2G deceleration at 2nd 10k.
 

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Discussion Starter #68
Some great knowledge shared. But some more feedback is needed on how not to crash like in video over and over again.

Some of provided feedback helps. But I still don't have an exact detailed sequence of what to avoid. Trailing braking 1/3 of corner could work. But it does not solve the root cause of the issue. Watching pros videos with their throttle and brakes, they trail brake few feet before apex in similar turns (46, 93) at Assen.

Obviously, it's a combination of braking and lean angle. Should I release the brakes completely a bit before the apex? What's the proper place to release the brakes fully in a corner?


BTW: I have been traveling, have not had time to upload parts of multiple laps yet.
 

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Some great knowledge shared. But some more feedback is needed on how not to crash like in video over and over again.

Some of provided feedback helps. But I still don't have an exact detailed sequence of what to avoid. Trailing braking 1/3 of corner could work. But it does not solve the root cause of the issue. Watching pros videos with their throttle and brakes, they trail brake few feet before apex in similar turns (46, 93) at Assen.

Obviously, it's a combination of braking and lean angle. Should I release the brakes completely a bit before the apex? What's the proper place to release the brakes fully in a corner?


BTW: I have been traveling, have not had time to upload parts of multiple laps yet.
Maybe it's not your braking at all, or throttle, or thermodynamics issues. Maybe your front tire really was toast and didn't have enough rubber to hold traction at that speed/lean..
 

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Discussion Starter #70
Maybe it's not your braking at all, or throttle, or thermodynamics issues. Maybe your front tire really was toast and didn't have enough rubber to hold traction at that speed/lean..
Tire is a big part of it, tire guys mentioned lower edges were worn and should have replaced the tire the day before. It's crazy the bars on shoulder still had at least 1.5mm in them.

But better to assume it's my technique and not blame it on tire like most riders do. Or at least learn how to manage tire wear better.
 
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