Slipstream distance is still too far

[Arvoss]

In my opinion the slipstream distance is still too far/overpowered. I took this screenshot when I was already affected by his slipstream. It started 10m before.

[Hawk]

That's a very big 10m distance. Lol 

But yeah, I know what your saying.... Maybe it could do with setting at about 3 bike lengths, 4 including the rider in front.

There should be a scientific formula for this slipstream effect? How about it Max? This is your arena; it's always great to hear how these things actually work and are worked out.   

[HornetMaX]

That's a very big 10m distance. Lol 

But yeah, I know what your saying.... Maybe it could do with setting at about 3 bike lengths, 4 including the rider in front.

There should be a scientific formula for this slipstream effect? How about it Max? This is your arena; it's always great to hear how these things actually work and are worked out.   

I've little knowledge in aerodynamics (just the basic stuff). I remember the slipstream being way too important in beta 3 and much better in beta4, but I've heard other respectable opinions that it is still a bit too much.

Notice that it's a pita to evaluate properly as it depends obviously on the speed and (maybe in to a smaller extent) on the bike front section.
You'd need the bike running on a straight at a fixed speed, note down the throttle position, then repeat with a bike preceding you at various distances and with you keeping the throttle open a tthe very same position as before (and bike aligned right behind the other one), then check if the resulting acceleration is acceptable ... in 2 words, no go.

I wouldn't care too much about a scientific approach here: Piboso's model is probably good enough and just needs a little tuning to lower the impact. If a couple of riders with real race track experience agrees on that, I'm for it.

MaX.

[BOBR6 84]

Neil spalding will know lol

Tough one..

I would agree with around 4 bike lengths in general..

Me on my oldschool R6 against other oldschool yams and CBR's.. Its hard to tell, a track I race at, Darley moor. Has a very long straight but sometimes I can be tucked in behind someone and still not make any ground.. Sometimes it sucks me right in and straight past!

Depends on the run onto the straight as well I think!

I guess motogp bikes would benefit more from slipstream because of the speed they do?

[C21]

4 bike length are about 9 meter.
In my opinion its too much.
i would agree 3 bike length out of personal experience where the draft takes a noticable effect.
Another story is when 2 bikes are driving next each other , in this case you´ve got a huge slipstream area (it´s like a bus driving in front of you).

[Desteban]

4 bike length are about 9 meter.
In my opinion its too much.
i would agree 3 bike length out of personal experience where the draft takes a noticable effect.
Another story is when 2 bikes are driving next each other , in this case you´ve got a huge slipstream area (it´s like a bus driving in front of you).

+1

[HornetMaX]

i would agree 3 bike length out of personal experience where the draft takes a noticable effect.

At which speed ?

MaX.

[C21]

sorry but i don´t have a speedo on my track bikes 
maybe 180km/h upwards

[HornetMaX]

sorry but i don´t have a speedo on my track bikes 
maybe 180km/h upwards

Do you (or Desteban or any other rider with track experience) think/know if the speed makes a diffrence ?
I mean, OK, below a certain speed slipstream is just not there or is irrelevant, but let's say between 200Kmh and 280Kmh ...

MaX.

[Arvoss]

I think slipstream does not affect bikes very much. In formula 1 you can easily overtake someone with slipstream but in MotoGP you barely gain speed. You're just able to get closer and overtake him in the corner. In GP Bikes you gain 25kmh or so.

I tried to find information about slipstream/draft on Google but I couldn't find any. Then I tried to find a clear overtake (birds eye view) on youtube but I couldn't find a good one...

[LoriX]

sorry but i don´t have a speedo on my track bikes 
maybe 180km/h upwards

Do you (or Desteban or any other rider with track experience) think/know if the speed makes a diffrence ?
I mean, OK, below a certain speed slipstream is just not there or is irrelevant, but let's say between 200Kmh and 280Kmh ...

MaX.

Yes it does make a difference, more speed=more air resistance you are not slamming into because you are tucked in behind someone. So yeah, big difference comparing let's say 150Kmh and 250+Kmh.. Of course it all depends on how fast your exit from the previous turn was.

[HornetMaX]

Yes it does make a difference, more speed=more air resistance you are not slamming into because you are tucked in behind someone.

Hmm but that's not the only factor.
Actually my question was more related to the distance the slipstream works on: is it bigger at higher speeds or not ?

Just got a brillant idea, I'll ask my wife (she's into applied maths, parallel computing, PDE etc).

MaX.

[Alby46]

Hmm but that's not the only factor.
Actually my question was more related to the distance the slipstream works on: is it bigger at higher speeds or not ?

Just got a brillant idea, I'll ask my wife (she's into applied maths, parallel computing, PDE etc).

MaX.

for me, it depends on the distance: the faster the one in front of you goes, bigger is the quantity of air it moves ( sorry for my italian-english lol ). Just my opinion

[Arvoss]

Look at 0:50. 4 riders are riding at top speed. The 4th seems to get closer to the 2 guys but not super fast. I think this is a very good example of the slipstream. (Straight, top speed).

https://www.youtube.com/v/BzWf-6UzQUA

[Hawk]

If two riders are going at top speed and the second rider in the slipstream has a different gearing ratio than the rider in front, then it is quite possible that the rider in the slipstream cannot catch the rider in front even with the advantage of the slipstream, in fact he could well blow his engine trying to pass the rider in front if there is no rev limiter on his bike. This is just one scenario you have to think about when both riders hit top speed before the rider behind can take advantage of the slipstream effect. So it's not always a case that the rider in the slipstream can overtake the rider in front if they have both hit top speed unless he has something left in his gearing and rev limit to do so.