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R/C Tech Forums Thread Wiki: New Schumacher KF2
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Welcome to the KF2 Wiki!

Please feel free to add any Tips, Tricks, or anything that would be beneficial to the KF2 Family

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Suggested Gearing

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17.5 I ran 69/31 at SRS Scottsdale Arizona and 72/30 at MHOR Aurora Co and Full Throttle ALB, NM RCM lockout worked excellent!


MIP pucks excellent upgrade! The new RCM lockout is an excellent piece as well! These options will greatly reduce weight throughout the drive line!

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Old 08-04-2015, 07:14 PM   #406
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The car with the red pack and the blue pack are both using LCG packs.
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Old 08-04-2015, 11:11 PM   #407
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Euros track seems having a lot of grip, blue/black groove and most of asso lads run 3 gears transmission.
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Old 08-05-2015, 04:07 AM   #408
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Default Red pack Buggy

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Originally Posted by motorcitymatt View Post
Excellent! Those are all really nice photos and what a privilege to get those along with a first hand account from the team manager.

Some observations:
  • From what I can tell it looks like all but Orlowski's car are using the small bore shocks
  • I see quite a few titanium screws throughout all the cars. They are probably trying to save some weight that can then be redistributed to the rear
  • The car with the red battery pack has a different top brace than the other two, which matches the one in the photos of the production kit
  • I think all of them are using MIP shiny drive CVDs + pucks
  • The car with the red pack also has the lighter colored toe blocks, which may be something heavier than aluminum alloy

And from what is sounds like from Trish via Muz, it is just like I was saying a few posts back, they are relying mostly on the dynamic forces of the motor to manipulate the chassis. The only thing that doesn't square with my initial measurements is that going to the lighter pack actually results in a more rearward distribution. But seeing as how I don't even have the conversion parts yet and was mostly eyeballing the placement I could have had the battery out of position. I will know for certain tomorrow night after I get the conversion done.

I got a chance to watch a couple of the qualifying heats using the link Tony provided. Orlowski's car and Pinisch's car both looked really on point. I didn't see anything to make me think that they were struggling to find rear traction. They both should be in the A-main no problem with where they have qualified so far.
I noticed that the red battery buggy has a different top deck brace! Reversed?
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Old 08-05-2015, 07:50 AM   #409
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Ya it seems to be grooved up in places and still a little slick in others.

Ill ask about the upper decks
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Old 08-05-2015, 07:56 AM   #410
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The upper deck on the car with the red pack matches the production part photos on Schumacher's website.

http://www.racing-cars.com/products....&pagewidth=550

I am betting the other cars have earlier pre-production parts.

The way the front end hooks up seems a lot beefier on the production part.
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Old 08-05-2015, 05:19 PM   #411
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I got my upgrade kit in the mail today and have put it together, but no track time yet. If you choose to not use the hold down bars (tape the battery in), you can mount the battery further back as close to the motor as you'd like. I'm not at home at the moment to measure, but you can go approx 5mm rearward not using the hold down bars.

I can't wait to track test this baby!
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Old 08-06-2015, 10:54 AM   #412
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I got the MM conversion installed last night and I must say I am really scratching my head on this. After the conversion, the F/R weight distribution (using the identical method i have been using) went all the way to 42.5% / 57.5%. This is with a 210g shorty lipo. I put in a 150g lcg lipo and this changed things slightly to 42% / 58%. This is a full 5% shift forward from the configuration I had been testing with the super shorty lipo and the ESC in the back.

Now the proof is in the pudding of course. I am going to track test it tonight and will share my results.
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Last edited by motorcitymatt; 08-06-2015 at 11:42 AM. Reason: incorrect figure
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Old 08-06-2015, 11:18 AM   #413
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Default Not Good!!!!

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Originally Posted by motorcitymatt View Post
I got the MM conversion installed last night and I must say I am really scratching my head on this. After the conversion, the F/R weight distribution (using the identical method i have been using) went all the way to 42.5% / 57.5%. This is with a 210g shorty lipo. I put in a 164g lcg lipo and this changed things slightly to 42% / 58%. This is a full 5% shift forward from the configuration I had been testing with the super shorty lipo and the ESC in the back.

Now the proof is in the pudding of course. I am going to track test it tonight and will share my results.
Matt those were not the numbers I think any of us excepted! Tony I think had concerns with battery forward? I was excepting 37/63 (+- .5) your numbers are not even close. Jpdanger had a good idea on removing battery post and taping the battery in instead, should move battery back some! He had no numbers as of this time but est. 5mm + I would move the ESC to the R/rear this should help some as well.

Last edited by MelKF2; 08-06-2015 at 11:24 AM. Reason: More info
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Old 08-06-2015, 11:36 AM   #414
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It's like I have been speculating, this conversion is probably mostly about using the motor to increase the dynamic F/R weight distribution under acceleration to get a lot more weight on the rear.

The motor is going to produce a force under acceleration pointed down and towards the rear of the car. The downward part of that force is going to push the car down at the location the motor is mounted. The rearward part of that force is going to want to lift the front end using the motor mount as the lever.

If you look at the position of the motor in the three possible configurations the downward force in the regular front-most position may actually nose the car down slightly, while the rearward force might very slightly sit it down and perhaps even balance it out, thus flattening the car. The low-grip position is almost right in the middle but perhaps a little back of middle. This will sit the car down under acceleration and perhaps lift it up in the front a little. Now the MM position is basically the same as the low-grip but with just more of the same effect. Hopefully, a lot more.

This is all me approximating things of course and I don't have any evidence to specifically back up any concrete claims. But I am pretty confident of the physics regarding the motor and what they are at least attempting to do roughly with its position.

We'll see how it goes.....
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Old 08-06-2015, 03:58 PM   #415
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Quote:
Originally Posted by motorcitymatt View Post
It's like I have been speculating, this conversion is probably mostly about using the motor to increase the dynamic F/R weight distribution under acceleration to get a lot more weight on the rear.

The motor is going to produce a force under acceleration pointed down and towards the rear of the car. The downward part of that force is going to push the car down at the location the motor is mounted. The rearward part of that force is going to want to lift the front end using the motor mount as the lever.

If you look at the position of the motor in the three possible configurations the downward force in the regular front-most position may actually nose the car down slightly, while the rearward force might very slightly sit it down and perhaps even balance it out, thus flattening the car. The low-grip position is almost right in the middle but perhaps a little back of middle. This will sit the car down under acceleration and perhaps lift it up in the front a little. Now the MM position is basically the same as the low-grip but with just more of the same effect. Hopefully, a lot more.

This is all me approximating things of course and I don't have any evidence to specifically back up any concrete claims. But I am pretty confident of the physics regarding the motor and what they are at least attempting to do roughly with its position.

We'll see how it goes.....
Got it!
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Old 08-06-2015, 10:19 PM   #416
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Quote:
Originally Posted by motorcitymatt View Post
It's like I have been speculating, this conversion is probably mostly about using the motor to increase the dynamic F/R weight distribution under acceleration to get a lot more weight on the rear.

The motor is going to produce a force under acceleration pointed down and towards the rear of the car. The downward part of that force is going to push the car down at the location the motor is mounted. The rearward part of that force is going to want to lift the front end using the motor mount as the lever.

If you look at the position of the motor in the three possible configurations the downward force in the regular front-most position may actually nose the car down slightly, while the rearward force might very slightly sit it down and perhaps even balance it out, thus flattening the car. The low-grip position is almost right in the middle but perhaps a little back of middle. This will sit the car down under acceleration and perhaps lift it up in the front a little. Now the MM position is basically the same as the low-grip but with just more of the same effect. Hopefully, a lot more.

This is all me approximating things of course and I don't have any evidence to specifically back up any concrete claims. But I am pretty confident of the physics regarding the motor and what they are at least attempting to do roughly with its position.

We'll see how it goes.....
Your correct, that alone will add grip by introducing more favorable leverage.... will that alone make the different we need? Time will tell.

Adding weight is always a popular avenue for tuning in europe as they dont get the practice and track time we usually get over here. Muz mentioned adding 40+ grams in the rear... that does a few things to the handling depending on where you place it... Im interested to see the setups from the race more than anything
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Old 08-07-2015, 12:02 AM   #417
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Quote:
Originally Posted by motorcitymatt View Post
I got the MM conversion installed last night and I must say I am really scratching my head on this. After the conversion, the F/R weight distribution (using the identical method i have been using) went all the way to 42.5% / 57.5%. This is with a 210g shorty lipo. I put in a 150g lcg lipo and this changed things slightly to 42% / 58%. This is a full 5% shift forward from the configuration I had been testing with the super shorty lipo and the ESC in the back.

Now the proof is in the pudding of course. I am going to track test it tonight and will share my results.
You are pretty spot on.
I got the same results as you. Changing the batt weight is quite negligible, as it is right in the middle. I have attached 4 photos of my various KF/KF2 setups in the past many months....

From KF Fwd Motor > KF2 Low Grip -> KF 2 Low Grip with ESC backwards -> KF2 MM.

The MM F/R distribution is more or less the same as what I had for KF Fwd Motor..................
Attached Thumbnails
New Schumacher KF2-kf-std.jpg   New Schumacher KF2-kf2_low-grip.jpg   New Schumacher KF2-kf2_low-grip-esc-backwards.jpg   New Schumacher KF2-kf2_mm.jpg  
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Old 08-07-2015, 06:17 AM   #418
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But when will be the sv3 released.?!
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Old 08-07-2015, 06:34 AM   #419
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Quote:
Originally Posted by leongkc View Post
You are pretty spot on.
I got the same results as you. Changing the batt weight is quite negligible, as it is right in the middle. I have attached 4 photos of my various KF/KF2 setups in the past many months....

From KF Fwd Motor > KF2 Low Grip -> KF 2 Low Grip with ESC backwards -> KF2 MM.

The MM F/R distribution is more or less the same as what I had for KF Fwd Motor..................
I will be testing the mm KF2 tonight.
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Old 08-07-2015, 08:02 AM   #420
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I finally bit the bullet and ordered my kf2 with the mm conversion and alloy rear trans housing. Cant wait to get it and test it out. I read somewhere that the b5 wheels wont fit the front of this car because they are too thin. Can anyone confirm this?
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