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View Full Version : Grip on RCP track


Mitchell
2013.12.29, 12:13 PM
Our races are traditionally on smooth side of RCP track and we will keep this tradition.

What can you recomend to increase grip espetially in the rear axle of mini-z ?

Chemical grip liquids are prohibited. Also foam and silicon tires are prohibited.

We have two cathegories
- Standard = fully serial miniz RM/MM with basic MZ09P motor, no tuning parts
- Open = all tuning posible, all motor performance, incl.VE

Espetially in more performant Open cathegory the problem of the grip is evident.
Very often rear of cars "shoots out" during acceleration.

What tires to use and how to prepare rear tires for the best grip ?
Differential tighteness ?
What ICS setup and eventualy what transmiter setup ?
What else can you recommend for each of both cathegories ?

Thanks for sharing your experience

mleemor60
2013.12.29, 01:35 PM
You are leaving a great deal to the imagination. Especially in the areas of what the RCP is laying on. Wood or Concrete? Carpet or bare floor? Conditioned or unconditioned air? Any of these variations will cause significant changes in available traction. Ideally you want RCP over a carpeted surface as a moisture barrier with an ambient temperature in the low to mid 70's and relative humidity below 70%. With these conditions just about anything will work to a certain degree. Beyond that everything is car set up which will be different for most every driver based on individual skill as well as how they want the car to feel.

Generally stiffening the front to induce push either by spring rate, tire hardness or scrub radius will lessen the loose condition brought on by idiotic amounts of power. Also if you have an upper end radio there are dozens of options that can help in controlling power application. Charging batteries at a reduced rate to decrease the immediate "punch". Using a higher gear ratio to kill the power off corner. Running the dif a tad less tight. Above all, proper tire selection to establish a good baseline. Remember. When going through this, practice time is your friend. Brute speed is not!!

EMU
2013.12.29, 03:47 PM
In general, reduce power until you no longer kick out. I would recommend using the fastest motor that doesn't lose traction. This is more effective than using a faster motor and dialing it back. Something like an ATM Standard/Stock BB, 50t... If those are still producing too much wheel spin, an ATM USA 60t or PN 70t would be a good option.

Speed is only good if it is controlled... If there isn't enough grip to put the power down, you are better focusing on corner speed and consistency.

Given that you haven't written any information about your current setup, I will just say to try your best to dial out any tweak in the rear end. That will make the car accelerate straight when the wheels are not turned. Softer rear end suspension will gain more traction on throttle, and push out of the corner a little more, making it easier to control as it loses traction.

What is the tire of choice that you guys run, and do you use radial/slick?

Mitchell
2013.12.29, 06:54 PM
Sure, too much of power not useful on RCP. Thats why we are running Atomic Standard or now VE+PN5500. But even here problem to keep the car straight on in acceleration.

Transmitters generally EX5UR (much better than KT18).

Floor under RCP generaly wood, not heated.
http://www.rcteam.cz/clanky20/20130317GP5.php

In Standard no tuning, in Open : DPS, MM or LM plastic or alu Pods, fiberglass Kyosho bottom plates, kyosho or Atomic ball diff. Ratio 8-9-10/43.

Using tyres Kyosho MZW38-20 (10) in the rear.
New one sharp on the track, but not so much of time (even after cleaning).

Acceleration with keeping straight line is our often problem on the smooth RCP surface espetialy in Open cathegory.
Logicaly not so big trouble in weak Standard cathegory, where small torque and small power of motor doesnt allow rear end acceleration shooting.

DMALMAD
2013.12.29, 09:51 PM
are you taping or gluing your rear tires to the rim if you aren't it doesn't matter what you do you aren't going to find traction.

chad508
2013.12.29, 10:42 PM
to me it sounds like a diff problem. does it seem to pull one way all the time on trottle. alost like the thrust bearing is bad or dry. as for tires i found the pn radial 6's to work best on smooth rcp

DMALMAD
2013.12.29, 10:47 PM
wouldn't be the diff if they are slipping on acceleration, maybe if they were spinning out in the turns it could be the diff.

EMU
2013.12.29, 11:33 PM
Definitely sounds like it could be a diff issue. What differential and wheels are you using? Some differential/wheel combinations don't work very well. Thicker wheels like the ATM dish wheels can often bind up the wheel bearing. Could be a possibility? (my fix for that is to use an AWD bearing that is 2mm compared to the racer bearing that is 2.5mm wide). If the diff action feels very tight, and the differential is somewhat loose, try loosening the rear right wheels' nut and if it improves, this could be the/one of the problem/s...

Kyosho 10d are very soft, so they will lose traction quickly. Kyosho 20d radial, or PN 6d radial may be better options. With any soft tire, you should at least tape them to the wheel, otherwise you may spin the tire on the wheel...