Track racing - set up and riding style

mmm…. first session without a new best lap.

I made some small changes from last week. 2 degree more in the front truck. Wheel pulley from 60t to 42t. And the back truck got a little riser so the deck was level.

So todays set up looked like this: Front truck 57 degrees. Rear 35 degrees. Gearing 16/42. Motor max 70. Battery max 25. Stooge race wheels.

It actually felt pretty good. The turning was good both frontside and backside. I did not reach max speed as last time, so this wasn’t a limit. The acceleration was a little slower but it didn’t feel slow compared to last week where I got the fastes lap in my last lap with a drained battery.

I am a little puzzled why I did not cut time today. Last week it felt like I had a lot more in me if only the top speed had been higher.

Either I just wasn’t fast today or this setup just is a bit slower than the setup from last week, or I am slowly reaching the limit where I am close to how fast I can be on this track.

I think I will keep this setup next week and maybe change the VESC a little for more acceleration and see what happens. If I am still not fast there I will change back and see if the fastness returns.

The wheels still feels good on the track and I can lean good in corners. Feels secure.

IMG_8426

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Maybe lower the teeth on the motor pulley The speed should have gone up cause the motors are able to spin the wheels quicker with the smaller gears. But could have been something small like you were not as aerodynamic as last time

I have thought of playing with the motor pulley as well. The speed did go up today and I didn’t reach the max the setup could deliver. So the max speed wasn’t the limit today.

I think the limit was myself today. It is really demanding doing these fast laps. I have to really concentrate. I sweat like a pig, my heart is pumping and I loose my breath. I might not have been totally up to that today. You know Christmas hangover :slight_smile:

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Back in 88 I started building and racing dirt oval Stock Cars. An old timer was watching me hotlap and overdrive the turn entry. He advised me I was carrying too much entry speed and was causing the car to spend to much time in the center and that it was slowing my exit speed. It was the first time I heard the term, “back up your entry.” Pinching the entry or turning in early has much of the same effect as over driving entry speeds. Fast turns are about using the correct entry Arc and speed that maintains momentum through the apex. From my personal experience when it all comes together the corner speed feels slower and with less input effort.
Gearing: acceleration from the center off is very very important. If it was me, I would put the 60t back on and bump the pinion to a 17t. On 10s 190kv it would put you at 37-38kph vs the 16/42 which is closer to 50kph and limiting drive… A 12/42 would yeild the same results as a 17/60 for final drive. :checkered_flag::checkered_flag:

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They actually talk about what Moe is talking about on older seasons of Top Gear. A slow in to the turn to clip the apex and fast out of the turn.

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For anyone interested in rc car setup (and not only rc) do a search for “XXX main chassis setup guide”. It has invaluable information for the understanding of car dynamics. You can also register here for free for the time being and see all that info http://learnsetup.wpengine.com/

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Is it the case that the softer the wheel the better grip?
What hanger width is best for grip?

There is no singular answer to these questions. Read the link I posted. All of it. If you would like pm me your email and I will send you a copy of the book.

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Woo a book. That’s a lot of info. Interesting I’ll check the link thanks

Think you are right. I did go fast in to turns today. The staff talks about sacrificing (lower speed than you think is necessary) corner 1 and 7 in order to have throttle longer in the stretch after those corners.

What do you mean about the “center”? (“causing the car to spend to much time in the center”…“acceleration from the center off”…) is it in the apex of the turn?

I will play with the motor pulley. I think if I can get something between 16/42 and 16/60 it would work pretty good.

And I will start working more on how to do the turns. They have this map:

Edit: when I look at it I have been starting the cornering too early. Will see how it feels to go later in to the turn to be able to throttle sooner out the corner. But to be able to do that I might need to be able to turn sharper than now. We will see.

Line-Map

Green: Throttle. Red: Brake. Yellow: Coasting.

Turn 1: Pull to the right, brake late and hard. Cut the turn in a late apex, for a wide entrance to the turn.

Turn 4: Do turn 3 so you get all the way to the right for turn 4. Brake late and shortly and start the turn. Throttle again at apex.

Turn 5: Keep all the way to the left. Let go of the throttle or brake shortly. Throttle again at apex.

Turn 7: Start the turn late. Brake shortly after you reach the first apex. Turn without sliding. Keep a constant steering angle round the corners before the straight stretch.

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There are 3parts to any turn. Entry ,Apex and exit. Entry is used to setup the Apex (turn center). You should have turn speed and race line established on entry for the appex and exit. The Apex should be rolled through without drive or brake forces being applied. It allows lateral forces to be applied at maximum efficientcy without drive or brake Dynamics subtracting from lateral grip. When carrying too much speed or pinching the entry you lose kph throu the apex while trying to maintain the perfered race line. .1 second here .2 second there it adds up quickly. Setting up the entry is the key to making fast corners.

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I fund this 24 video tutorials on driver technique. I will see what I can gain from that.

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I kept the setup from last week. I now want to focus more on how I ride the track than the setup. I have begun to watch and read the tutorial I link to above. And I want to slowly work on some of the many suggestions they give. I had 3 main focus points in this weeks session:

  1. Entering the turns a little later than before and trying to do a later apex (this taken from the first tutorial).
  2. Trying to find the optimal speed entering the turns. In my case meaning I have to enter them a little slower, as Moe suggested after last week.
  3. Looking at the apex before I enter the turn. This is taken from the tutorial 3 “IMPROVING VISION ON TRACK”

And then at the end of the session I added a fourth focus and began to work on braking before the slowest turn on the track.

I find it every every difficult to get the same speed and starting turning point each time. And this affect hitting the late apex a lot. Sometimes its spot on, and next time I go through the same part of the track its way off. This track racing is difficult but I guess it’s a matter of practice. The good thing is that I really feel when its spot on. It feels so good! I didn’t have that many good laps today. I still have a tendency to approach the turns with to much speed, but I did cut time and had a couple of laps that was better than the previous best lap.

Being aware of the where i look really felt good. I got better prepare for the turns and it just felt really good to be looking ahead.

I started to work on breaking before turns. Up till now I have just been coasting. I have not felt that I was ready to work on breaking yet. To much to control and to much going on. And I am very sensitive when the board jerks with hard acceleration and when letting go of the throttle quickly or braking hard. This throws me off. But it seems that I am ready to work on that.

Gearing: As Moe suggested last week I think I will work on the gearing. This 16/42 is to slow accelerating out of the turns. Especially when the battery drains. Will go back to 60 on the wheel and see if I can find a 17 and 18 motor pulley to play with. I am just really bad in fining stuff. Does anyone know where to get them. Have to fit the Maytech motors with 8mm bore and key.

Best lap today was 37.19. Nad after I began to time my laps it have been looking like this:

41.50 sec 40.50 sec. 38.93 sec. 38.53 sec. 37.67 sec. 37.49 sec. 38.78 sec. 37.19 sec.

IMG_8560

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U ever try front drive vs rear?

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Not yet. That could be fun. With my deck being the same front and back, I could just swap bushings front - rear and swap the motor wires so the motors runs the opposite way. Right?

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If you have vesctool you could reverse the motor sens :v: Edit: or directly with an apps like metr.pro

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I am using perimetr and metr. Is it possible from these apps.

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Yes, it is what I used :wink:

Adit: but now its named expert mode in Metr app or something like that.

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This thread is driving me insane. It describes exactly what I want to be doing… huge thrill, the best way to get to understand your board geometry and dynamics and all in a safe and controlled environment.

It’s driving me insane because there isn’t a single kart track in the Netherlands that will allow us esk8rs to come and play :sob: Seriously! We’ve got the money and the numbers and all our own f ck ng gear! I don’t get it.

What’s your secret, @davidbonde? Are these guys friends of yours or are the Danes just a bit more friendly?

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Yeah… I feel really lucky. There are a couple of kart tracks near me. This one has electric karts, so I thought that they might be more prone to letting electric skateboards in. I went there in person and talked to them. They were very friendly. They had to think a little about price. It is a business and even though they would love to help, they also wanted to earn a little. They let me in just before opening hour where I can have an hour for my self. If I wanted to come in their opening hour I would have to pay what the can sell an hour of track racing for.

Its a really nice place and they are pretty proud of it. They have real race asfalt laid and because its electric karts there are no spill or anything on the track.

I think its the perfect solution. I come and do my thing. They dont have to be involved at all, and they have people there anyway, so they get a little extra income.

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