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Lane Changer Help (3-Lane)

Discussion in 'Technical Help' started by celt63, Oct 29, 2017.

  1. celt63

    celt63 Lock Nut

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    Greets,

    Looking for some ideas or direction. Most of us at our track struggle with the standard 3-lane, lane changer. If we CO, it's almost always at the lane changer. Box stock...no problem, but as soon as we drop in something even a bit faster, we start to struggle. I've probably put the most time in research as anyone at our track. I've have front brakes the just touch at slope and 1mm clearance at my rear brakes.

    Then I see this at the Dojo:


    Now I understand, these guys are world class tuners, no doubt. But how on earth are they ripping through that standard lane changer that fast and no CO? There is no way I can get through that at even 1/4 that speed. (changer just to the right of Jonathan)
     
    Last edited: Oct 29, 2017
  2. Drew

    Drew Carbon Fiber Dust

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    There's plenty of different ways to tune for it I'd imagine, check this one one out for different method:

    I know it's a simple explanation for stock build, but it's also an interesting insight.
    There's been other methods too, such as inverted dual roller with rubber ring on front so the rubber ring is set lower or double stacking the rollers low at the back with just a stabilizer dish at the top (seems popular in indonesia).

    I guess, it's not all just about the brake.
     
  3. acid.funkid

    acid.funkid Screw

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    Have you tried setting the angle of your front rollers so they thrust a bit downwards? This should help keep your machine down, at least that's what I can think of right now.
     
  4. warwick

    warwick Spacer

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    Worrynot, 3 LANE standart LC is my kryptonite too, but on those vids, do you notice the big ass stabilizer on the front?

    Yep, those things size usually 1 or 2 mm smaller than the roller, so it's hold, and stabilize then prevent too much tilt when car hit the first uphill on the LC.

    That and front bumper roller angle
     
    Last edited: Oct 30, 2017
  5. celt63

    celt63 Lock Nut

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    Running an MA, so they tilt down a bit. Maybe I should try plastic ring rollers or even something as drastic as some of the rollers with o-rings for even more bite.
     
  6. celt63

    celt63 Lock Nut

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    I think it would help to get a GoPro setup and see slow motion - exactly what I need to do. I've got -1mm high stabilizers in the front, I think we are simply shooting higher than the track fence and launching out. You're right, need to find a way to keep the nose down to give the stabilizers a chance to work.
     
  7. warwick

    warwick Spacer

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    Can i see your current car setup with its brake setting and such?
     
  8. celt63

    celt63 Lock Nut

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    warwick,

    Here is a top shot, I'll snap the brake when returning home from work.
     

    Attached Files:

  9. Chris Lee Design

    Chris Lee Design Aluminum Lock Nut

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    ah... the dreaded 3-lane , LC. I agree with warwick and acidfunk.

    1) Roller angle, the natural angle of the MA chassis may not be enough to down thrust your car. Stick with the aluminum rollers like you have because they have more gripping force on the walls to keep your car down, might even think about the 12-13mm rollers - double stacked ones. The sacrifice here is you will be slower everywhere else on the track (but so will everyone else). I've never mounted on the top of the MA chassis, I usually cut off the front, and mount from the bottom then add an angle plate. On the flat mounting plate, I can get away with 5-7deg angle for the LC at really fast speeds.

    2) Strong front stabilizer, your wheel cut outs should be good enough. I think #1 is more the culprit.

    3) Rear Brake, I noticed on my car that It did well with a lower rear brake setup, but also depends on the track. May not be able to get away with 1mm brake setting if you have a lot of banks etc.

    I wouldn't use plastic because it's not enough grip, and o-rings imo, have poor performance everywhere else compared to non-O-ring. Slow-Mo video helps a ton!

    Hope this helps. If you guys need help with making angle plates, I might be able to CNC some for you guys, and you can buy it through Dxnprovisions.
     
  10. Drew

    Drew Carbon Fiber Dust

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    What about offset o-ring rollers? For example, the dual alu front roller flipped upside down, this way only the large roller connects to the wall while the o-ring only grips after the wider part gets higher than the track wall?
    Or the same on the rear, so like similar to my Savleo, the o-ring roller is offset to the upper roller (2 different sized rollers) so it works the same as I've laid out above?

    I mean, this setup can offer 2 points, first being the o-ring will be used as a semi brake if needed and secondly when compared to how a car normally wants to roll (opposite side to the wall will want to roll up), once the car lifts off the track surface, due to the inverted/offset roller preventing typical roll, the car should theoretically take the roll of least resistance and try to roll down on the side opposite to the wall.
     
    Last edited: Oct 30, 2017
  11. Chris Lee Design

    Chris Lee Design Aluminum Lock Nut

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    I personally just don't bother with O-rings. I am faster without them. And also this is all about racing and in racing communities there is a meta. Those guys using flipped 13mm o-rings it works for them, but if everyone uses them, they are kinda on even ground. Here...I'm racing against really fast guys, who don't need the o-ring setup to stay in, so I'm being forced to adapt and go faster. You can use the o-ring if you want to try it, and it probably would work, as lot of setups would. I can say that I've never seen an o-ring setup on the podium here so it's not something I'm rushing out to try. The last time I used the o-ring setup on 13mm double rollers was in that video Celt posted, the double lane change...I lost due to not being fast enough because of the o-ring setup, I was losing too much speed in the corners. Once I took off the o-rings it was a huge difference for me in speed and I was up to par with the winners.
     
  12. Drew

    Drew Carbon Fiber Dust

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    Were you using them offset though? From what you're saying it sounds like you were using a setup where the o-rings were always touching the walls around corners.

    This is what I'm trying to explain, using the image below as an example of the rear roller setup ( dual front inverted is exactly the same, just doesn't need offset ), when the car is running normally on the track, normal corners, the track surface would act as an opposing force meaning there is less resistance upwards, which would cause the roll indicated by the green arrow. This would essentially limit the car to only using the top roller for stability.

    On the other hand, when the car is in the air and hits a wall, there's no surface below to act as an opposing force, the top roller as the pivot and center of gravity would be below the pivot, this would use natural forces to cause the car to roll downwards by adding gravity/weight due to the lack of opposing force (purple arrow)

    offset roller theory.jpg As you say, o-rings act as brakes and in a normal setup, it would be braking every time it connects with the wall, rebounding down straights, corners, LC's.
    But with offset, the o-ring would only be activating as a brake under very specific circumstances, the car is in the air/not on the track surface and is hitting a wall. Because the way the offset works, it would be sort of like a fighter plane, as I goes around the corner, it will roll and bank itself back onto the track surface......at least in theory.

    That said, this will also work with non o-ring rollers too. It's another option available along with adding roller angle.

    I love to theory craft, but sometimes, I feel like I don't express myself well and people feel it comes across in a negative way which is not what I'm intending. So in short, I hope I don't upset people when I start getting like this.
    Also, I hate the word Meta, it's on my short list of words that make me cringe, along with insurance, premium, dlc, packs and loot boxes. Meta reminds me of that saying "I'm an expert at everything but a master at none." or like being "A follower of the herd, not the leader of the pack."
     
  13. Chris Lee Design

    Chris Lee Design Aluminum Lock Nut

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    Regarding the o-ring setup you're describing, yes I've tried it and it did not work for me, and I do not need it to make the lane change. Therefore It's not something I have to use. I can clear it without it, using regular rollers, and angle and still maintain high speeds.

    I can appreciate theory crafting, as I do it often, but I only post things that I've tested or have seen work repeatedly in a racing environment. I think this is the information people want from me and what I can contribute. I don't take your posts as negative, and I hope I'm not coming off as negative, there are many ways to achieve a goal, the question is how do you want to do it?

    Regarding the word META, I think we have different definitions of the word. META (Most Effective Tactic Available) to me means what trend I see ppl using to race to approach a specific situation. Like a META for right now is everyone uses some sort of rear hammer damper. That's the META for helping the back end stay down. Not that anyone is an expert, or a follower but that after all the testing they have done, this ends up being the META for it. There could be many reasons, like it's the easiest thing to make, or cheapest etc. This is how I use it, but I am not saying it's the right way.

    I encourage everyone to try and test for yourself, and don't take anyone's word as gospel.
     
    Last edited: Oct 30, 2017
  14. warwick

    warwick Spacer

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    Another thing that can happen is the stabillizer was too high. First uphill, car fly a bit but because the stabilizer was too high it failed to contact and prevent tilting.

    Sometimes happens
     
  15. Drew

    Drew Carbon Fiber Dust

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    Have you tried the indonesian style with double stacked roller low at the back and only stabilizer top? I'm curious to know what you think of that method. From what I heard, it works by helping move the weight to a lower position and also gives more roller surface area to grip when going through the LC, which could make sense as the top roller might not even be touching the wall.
     
  16. celt63

    celt63 Lock Nut

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    I'm going to try a double roller in front. perhaps 13-12...

    Change one thing at a time until I get the desired results.
     
  17. acid.funkid

    acid.funkid Screw

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    Let us know what works for you :)

    In this video (1:24), Roscoe said that he uses the 13-12mm double aluminum rollers (the one without the rubber ring) installed upside down just for the right side (the left one is installed normally) as it's easier to pass the lane change with this setup. You might want to try that as well.

     
  18. celt63

    celt63 Lock Nut

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    Wow, easy enough to do. Never thought of that.

    Now, for a more exotic option...this really intrigues me. Anyone no more about this - Italian setting!

     
  19. warwick

    warwick Spacer

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    Hi bro. Hows your progress with the 3way LC?

    Are you able to cross it now?
     
  20. celt63

    celt63 Lock Nut

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    Yes, much better....angled the front 13/12mm roller down a bit and much better!
     
    Last edited: Nov 15, 2017

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