Tip (1) Gear the car up!
Tip (2) Reduce friction.
Tip (3) Don’t waste your battery power.
Tip (4) Cleaning your motor.
Tip (5) Running in a Motor.
Tip (6) Batteries.
Tip (7) Weight.
Tip (8) Balance.
Tip (9) Reliability.
Tip (10) Tyres & Tuning.
Gear the car up!
I.e. replace your pinion with one that has one tooth more, then track test the car.
You will have a higher top speed, but it will slightly decrease acceleration.
How far can you go?
I look for two things: -
a) I drop back a tooth, if the car can’t reach its maximum speed before the end of the straight, or has poor acceleration.
b) Or the motor is showing signs of stress, (It’s too hot to keep your hand on at the end of a 5 Minute race).
Make sure your car is as friction free as possible: -
Polish your front axel & oil it at least every meeting.
Spin your wheels after every run, if sticking re-move any fluff build-up.
Fit ball-races to your rear axle, and remember to clean & re-oil them every few meetings.
Don’t waste your battery power: -
Buy a thick multi-stranded silicon rubber coated wire, to connect the battery and motor to the speed controller, you will need to do some soldering and it’s a good idea to fit bigger gold plated connecters, this will increase the punch & speed of your car.
Once you have an efficient electrical system, remember to check it by: -
Feel any battery or motor connectors at the end of a race to see if they have heated up, if so service or replace them.
Also keep an eye out for broken strands of wire where they attach to solid objects like: speed controllers and motors.
Clean your motor: -
Between every meeting service your motor by spraying it out with motor cleaner, (tip, I use brake or clutch cleaner in a well ventilated area) Its only £1.50 or less as apposed to £5 - £8 for the proper stuff). Cont . . ……
You must remember to re-oil your motor bearings, but never add oil to your motors comm.
It’s a good Idea to re-lube your motor brushes with some com drops.
Take a look at your communicator and if it’s not a nice shiny copper color, clean it with some metal polish, (I use “Goddard’s long term Brass & copper polish”, it comes in a blue bottle) and one drop on a cotton bud is all you need.
(Tip, make sure you leave no cotton wool behind or your motor will run slower or not at all!)
Motors need running in and they have a honeymoon period!
If you buy a new motor, first oil its bearings, second run it under water, (no I haven’t gone mad) for about 10 to 30 seconds only, or you will have no brushes left!
You should notice that the motor runs quieter and faster, (don’t leave it wet).
This will bed in the brushes, and flush out any muck from the inside of the motor.
Now polish the motor as in tip (4), and re-oil its bearings.
Your new motor will now be in its honeymoon period, i.e. its fastest period of its life.
Your motor can stay fast for weeks, or even months, but the first meeting you over gear your car or stall it against a wall, it’s over! (So always start with a small pinion and work up).
But it’s always worth water dipping, & re polishing an abused motor, to see if it will forgive you!
I always run a New motor, with a one tooth smaller pinion than a well used motor, as it revs faster when new, and you will keep it in it’s honeymoon period for longer.
And always drop down a tooth, if putting new large diameter tyres on the drive axel.
As a rule lower capacity batteries give more punch but less run time.
1400 mAh to 3300 mAh gives a good range to choose from.
Ni-cads respond well to the way you charge them, i.e. if you charge them fast they discharge faster but you have reduced run times.
A good charge rate for Ni-cads is 3.5 Amps for heats and 5 Amps for finals.
If your using Ni-MH batteries, charge at about 3.5 to 5 Amps, (the trick is to keep them as cool as possible, to keep them punchy). Use matched cells for your finals.
Keep the weight of your car down, and your center of gravity low (you don’t see 3 tone sports cars for a reason).
Balance your cars weight.
Balance your car, approximately 60%, on its rear axel, and 40% on the front axels.
Tip: - if your car is just a little down on front or rear grip, move something towards that end of the car, (receiver, speed controller or battery).
If a part let’s you down give it to your arch-rival, do not put it back on your car!
The number of times I have seen somebody pick up a wheel nut just after it let there wheel fall off, and stick it straight back on!
Use nylon locknuts whenever possible, & use liquid thread lock on bolts/screws if not threaded into plastic and don’t forget your rear wheels, (They must not slip).
I place just one drop of thread lock on the rear axle shoulder just before I place my rear wheels on, (give it time to set).
Avoid bending your wires about or letting them float about in the car, because metal is easy to fracture if you keep bending it backwards and forwards.
Tip (10) Tyres.
As a rule softer tyres give more grip than harder tyres, and most cars have softer tyres on the back because there grip is divided into two, some goes to push the car forward and some goes to stop the car slipping sideways.
Note: if you demand more acceleration by gearing your car down, you will have less sideways grip from your rear end! This might be a good thing if your car has a little too much rear grip.
Placing a larger diameter tyre on your inside front will increase your turn in grip but reduce your grip as you come out of the corner.
If you place a larger diameter tyre on the outside rear of your car it will turn in much tighter but you may have to fight it more down the straights, but this can be reduced by tracking your car at speed (adjust your steering trim then drive it flat out to check it runs straight).
You will not run perfectly straight at low speed but who wants to drive slowly?
(Try about 2mm difference between the diameters of your rear tyres).
Need just a little more grip?
If you need just a little more grip sand paper your tyres or use a junior hacksaw to place small groves or blades in your tyres.
Tip: place the tyres on the back of your car and spin them.
Now just hold the saw blade across your tyre (mind your fingers).
Still not enough grip? Put deep grooves in the tyre.
(I modified a junior hacksaw blade with a grinder to do this).
Tuning your car: -
A well-tuned car can be driven around the track using about ¾ of the stick on the corners.
If your car pushes to the outside of the track (Under steers) with your transmitter steering stick full over, you need more front grip.
Strait line stability (It should also run in a straight line)
1) First check your rear wheels do not slip.
2) Then add toe-out at the front (by shortening your track-rods)
3) Lastly keep your rear tyres identical, in size and compound.
(But staggering tyres can have big benefits on the corners).
Strait line stability For V12 drivers: -
The first thing to check if the car keeps pulling to the right: -
Check the spur gear and or the right rear wheel carrier are not slipping!
Also, if when accelerating from a standstill you car veers to one side, simply tighten the opposite side spring to where its going to cure the problem (if it goes right, tighten the left spring).
General V12 tuning: -
The suspension is easy to adjust; if your car spins easily, loosen it, and vice versa. Most drivers have fairly soft suspension for improved stability.
Other types of car: -
If your car looses it’s back end on the corners, and it sits pointing the way you just came from, you need more rear grip. (See my grip list below)
If your car roll’s over on the corners, reduce the weight in the top of the car if possible or try using a harder tyre on the outside front and make sure it’s outer corner is not rounded.
See my tyre grip list for a rough idea of how much grip different compounds give.
Tyre grip list, starting from the least grip.
Front tyres Rear tyres
Blue (H2G) Silver (PT) (Very low grip)
Orange (PT, tuff) Gold (PT)
Standard (M) (E2D) JAP SOFT (low grip)
Hi density (M) (E2D) Pink URFA (Hard wearing)
Red (PT) (E2D) 812 Medium
Gold (PT) Super soft yellow (PT) (good on dusty carpets)
Gray (M) (E2D) SE Medium (Good rear tyre)
Green (PT) (H2G) 891 (H2G) (good on sandy carpets!)
JAP MEDIUM Key: - M= Mardave PT= Precision Tyres
JAP SOFT H2G=Hard to get E2D= Easy 2 Damage.
Rebel racer hard (M)
Gray (PT) I like to start a car off on: Front (orange) rear