Post IMAGES of your MR-03

[JeremyC]

Originally Posted by naesager

you might notice the center spring pointing quite a lot downwards.. I don't guess that's normal, will figure it out eventually..

It looks like your DDS is installed fine, but where the front of the top shock is mounted is totally jacked. I can't tell by the photo exactly what is wrong, but it is def the front that is the problem.

Other than that the car looks nice, congrats

[Ronac]

Heres a few pictures of my MR03. I've been running it with this body since I got it in November or December.

Upgrades:

Kyosho stainless kingpins
Kyosho front spring set
Atomic bearings
Ray's RE-30 Multioffset wheels (0N 3W)
Atomic AW groove tires (30F 20R)
PN multilength disk damper
Custom "reverse sidewinder" motor mount
3Racing ball diff with 64p gears
Hybrid Kyosho xspeed motor with ball bearing can
Alloy front body clip (murcielago)
Gunmetal Lamborghini Murcielago

[JeremyC]

Originally Posted by Ronac

Heres a few pictures of my MR03.

That motor mount is pretty cool looking. How do you adjust the gear mesh?

[Ronac]

The mesh is adjusted by loosening the screw and adjusting the arm that the orange idler gear is attached to. The point of this motor mount is to reverse the rotation of the motor which will increase the rearward weight transfer under acceleration.

[Felix2010]

Ronac - This type of innovation is what I love about RC racing. Tuning and maximizing performance - That's what I try to do. I am not quite sure I understand the way your motor mount increases rearward weight transfer under acceleration. Could you explain further please? Also, doesn't the motor's pinion rotation spin counter-clockwise to move the car forward? This is the same as how the "normal" MR02/MR03 motor mounts work - With the motor pinion on the passenger side as with regular pods, the motor must spin counter-clockwise to accelerate forward. Or am I missing the point of your design. I am definitely interested in hearing more about your motor pod design.
Thank you!

[Ronac]

By switching the gears to the driver side, one would have to reverse the polarity of the motor. By added an idler gear in between the pinion and spur, they would have to reverse the polarity again. Since my motor mount does both, its reversed twice which means there needs to be no change in the wiring of the motor.

Have a read about the sidewinder layout for slotcars:

http://en.wikipedia.org/wiki/Sidewinder_(slot_car)

The purpose of the idler gear is to change the direction of the motor rotation relative to the chassis. If we look at the car from the passenger side, the conventional motor mount has the motor spinning counter clockwise. With this motor mount, the motor spins clockwise. The reaction moment/torque from the motor (which is opposite of the motor direction) now contributes to rearward weight transfer rather than forward weight transfer. Since one direction biases forward and one biases rearwards, the total change can be up to 15-20% in load on the rear wheels depending on the torque of the motor and gearing being used.

[Roger]

Here are my pics of my FPR Kyosho MR-03:

[EMU]

I have changed the body to a newer f355, will update later when I can take another pic...

[Skv012a]

Do I finally see a narrow front end?

[EMU]

Yep, its narrow. I got it wide, and switched it to narrow to suit the narrow class that we run. We can use any chassis, with a narrow configuration. Stock MR015, MR015 width MR02, Narrow MR03, and AWD with less than 2mm offset, all cars have to use 70t.

Fastest lap of the night last race was my AWD with ATM Stock BB/Porsche GT1 body, which turned a 9.94, and the car above turned a 10.14 with a 70t. Which was the fastest lap in class by more than .5s, and 3rd fastest lap in all classes... Not even a hint of traction roll...

[Skv012a]

No roll I'd attribute to body and slow motor, so sounds like 03 is doing its job hella better than 15 used to.

[Felix2010]

Originally Posted by Ronac

The purpose of the idler gear is to change the direction of the motor rotation relative to the chassis. If we look at the car from the passenger side, the conventional motor mount has the motor spinning counter clockwise. With this motor mount, the motor spins clockwise. The reaction moment/torque from the motor (which is opposite of the motor direction) now contributes to rearward weight transfer rather than forward weight transfer. Since one direction biases forward and one biases rearwards, the total change can be up to 15-20% in load on the rear wheels depending on the torque of the motor and gearing being used.

I understand what you mean about if the motor pinion drives the differential spur gear on the driver's side of the car, then to get forward motion the motor must spin clockwise rather than counterclockwise (Passenger side, standard motor config). But by introducing the "idler gear" to your design, aren't you reversing the rotation of the motor back to counterclockwise in order to get forward rotation for the car? In other words, wouldn't you achieve the wanted rotation result from not having the idler gear?

Sorry if I misunderstand, but I am confused because if you want the rotation of the motor's armature to spin towards the rear axle in clock-wise fashion, you would only need the "Idler gear" when mounting the motor with the pinion on the standard side (passenger side).

I really like innovation and proprietary homegrown ideas and parts. Keep 'em coming

[color01]

From the motor perspective, yes things are still going the same way, but when you hit the throttle, the motor torque will serve to tilt the rear pod backwards instead of forwards, which is what a normal gearing setup will do. Hitting the throttle with his prototype pod will take weight off the front wheels and shift it to the back.

It's an interesting idea, although I have no idea what kind of performance change it'll bring (other than a marginal decrease in drivetrain efficiency). You get more on-power traction at the expense of a looser rear end off-power, so it may be a good thing depending on driver and track.

[Ronac]

I started a new thread on my motor mount here:

http://mini-zracer.com/forums/showthread.php?t=33570

Felix, to answer your question about the direction, have a look at the car from the left side. On a regular car, the wheels rotate CCW and the motor rotation is CW. With the rotation of the motor being CW, the reaction torque will be opposite of that which is CCW. A CCW torque will transfer weight to the front.

On my motor mount, looking from the left side again, the wheels rotate CCW. Obviously that doesn't change. However, with the idler gear in place, the motor will spin CCW instead of CW. Which in turn means the reaction torque will be CW and transfer weight to the rear under acceleration.

Hopefully that didn't confuse you more.... Feel free to ask any more questions. I guess just do so in the other thread and we'll stop hijacking this one

Color, at our track, we tend to like to use the smooth side of rcp (less grip).We also like to set most corners up to be sweepers and try to avoid tight hairpins. I designed this mount with on power sweepers in mind because I was having troubles with putting power down with a mod motor. I agree that there will be increased drivetrain losses but with the case of mini z's, its easy to get a really powerful motor to overcome increased losses that but finding traction is the problem.

[Felix2010]

I think I see it now. Thank you Ronac and color0 for your responses. Definitely a cool motor mount Ronac. I wish I some equipment to manufacture some cutom ideas of my own.