TOP SECRET MINI SECRETS

A guide to everything you NEED to know...by the guy with more Mini Titles than any of us here. Tim wanted a last chance to win an event before he revealed all this, so we had to hold back until April 1st to let the cat out of the bag.

This is THE definitive guide, even more definitive than previous ones which we said were definitive. In fact in terms of definitiveness, this ranks right up there let me tell you! I don't think you'll find find anything with these sort of levels of definitiveness.
OK, I think I went a little off track there.....      Over to you Timmy. (definitively)

Please note, this is a JOKE article. It was our April Fools article for 2008. Please enjoy it for the amusement that we intended it to bring. And please don't try ANY of the things mentioned here! And stop emailing us and asking if it's true or not....

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The Black Art of Building a Race Spec Mini (Top Secret)
By Tim Keiller

A lot of people ask me why is my mini so fast? Is it the motor? The tyres? Have I altered the gearing? Slipped an extra cell in the pack? Am I a good driver?

Well the short answer to all of those questions is: No.

The long answer is … it's a combination of a lot of things.
Each tweak will give a 10th of a second here or a 100th of a second there, all of which can be lost quite easily if you run wide in a turn … but what if you don't run wide? What if you are on the best racing line, lap after lap, your consistency is below 0.3, and you never crash … but you are still being beaten because the other guy has more speed?

I'm not sure why, but I've decided to reveal here today ALL of the secrets that will get your mini going faster than the next guys (or girls) … just hope that the next guy isn't reading this article.

I have listed my “blackball” of top secret mods here … let us begin

#1 - everybody has heard of matched batteries right? Where some nerd in a factory gets paid to test every cell for their voltage and run time and pairs them up with another 5 cells of equal voltage and run time, a sort of twisted battery dating service where 6 cells are match made and live happily ever after … yes, we've all heard of that, but have you ever heard of matched bearings? As far as I know, I'm the only nerd who practices this mind numbingly boring procedure.

I've tried a lot of bearings over the years, metal shielded, rubber shielded, Teflon shielded, ceramics … well forget all the hype, neither are any better than the others. Buy a set of bearings and do a simple spin test with an axle, you'll find that some of your new bearings spin for a second or 2, and some spin for 5 - 10 seconds, why is it so? Because every manufactured item has tolerances, it is not possible to make every item identical, there will always be a 0.1 of a millimeter difference here or there, or even more.

Bearing up well under the strain	Spin, spin, SPIN!

So the way around it is to buy 3 or 4 sets of bearings for your next M03, then slowly go through them with a simple spin test.

First, I test each bearing with an axle as shown in photo 1, this is a quick and easy way to discover the free spinning bearings in your batch. Put all of these in your 'keeper' pile, the others in the 'sell on ebay' pile.

Okay, got enough for a whole set or 2? Now mount them on a rear upright and attach a wheel, get your stop watch out, spin the wheel as hard as you can, now time it. If you have faith in your arm being consistent, one “spin and time” will do, if you are worried that you can't put your whole strength into it every time then spin each bearing three times and take the average, or use a dremel to spin up the wheel.

Eyes down for bearing bingo!

#2 - Alright, this trick has been transposed from the stock touring car guys, but it works a treat!
I read on rctech about these tossers in stock racing cutting every 2nd tooth from their belts on their belt drive touring cars, the theory is that less teeth equals less contact area and less friction. But wouldn't cutting the teeth off weaken the structural integrity of the belt? And reduce the life span considerably? Well in modified racing yes, but stock motors don't have crazy amounts of power, so the belts hold up just fine, and since I noticed Tamiya release special pulleys for their TA05 with every 2nd tooth missing, I thought to myself “a-huh!”.

It's a very simple exercise to do, I use my trusty side cutters to rip through and cut every 2nd tooth from the gear diff gear, the long idler gear, and also the short idler gear teeth as well. I don't however cut every 2nd tooth from the pinion as this would go against the rules. Technically you have to run a 20 tooth pinion, if I cut off every 2nd tooth and end up with a 10 tooth pinion odds are that some loser in the B final will protest my car, and if they find I'm running less teeth I could lose my win, so just stick to cutting every 2nd tooth from the plastic gears.

You will find that less teeth means less friction, less rotating mass and also less noise. So if anyone asks why is your mini so quiet? Just tell them that you use Teflon spray to quiet the gears … or tell them you spend 3 hours putting shims in the gearbox, either answer is good.

This should knock off 0.3 seconds per lap.

Extra teeth - CUT!	Doesn't look neat - but works a treat!

#3 - people talk about springs and sway bars a lot, some run no sway bars, some run ultra hard, some insist on ultra soft springs some on ultra hard. Have you ever been to a real race track and tried to move the suspension on an open wheeler (Indy or F1 car) to see what happens? You can't move it, the suspension is rock hard!

Tamiya don't make springs hard enough, even their extra stiff or super stiff don't cut it, but there is a cheap and easy way to make a spring super duper hard … it's a manufacturing process called “quench hardening”.

Take the kit standard super mini cva springs, take your trusty flamethrower or lighter, then simply heat the spring until it is red hot, then drop it in a bucket of water - steam should come out and their should be a “choom” noise, this indicates a successful quench hardening.

This is my handheld torch, also makes a superb creme brulee as well, very versatile	As all good latte cup lids say 'Caution; Hot stuff can burn you, and it did!

Your tyres will wear faster as they tend to work harder with a stiffer spring setup, but we are building a race winning mini here, so bollocks to the tyre wear!

You should see a 0.1 second per lap advantage with springs and 0.1 with sway bars.

Hot springs often steam

#4 - Ever looked at the Tamiya rims and wondered what the ribs are there for? My guess is they are there for extra strength, but if you're driving fast, your tyres will only be lasting 15 - 20 minutes of track time, so you don't really need the extra ribs … so, cut them off, save on rotating weight, the wheels will spin up faster because the motor has less load to spin, which means you'll be getting to top speed quicker than the next guy.

This should see 0.1 of a second off your lap time.

Ribbed for your pleasure	Smooth sailing all the way

#5 - I once read that world champion r/c racer Masami, balances all his r/c wheels, in fact a lot of the pro drivers do this, and it makes sense really, you wouldn't drive your real car with unbalanced wheels would you? So buy a simple device like this prop balancer, get some lead tape (or plumbers flashing tape) and balance your wheels.

Does Sir require a balance?	Wheel of Fortune!

The heavy point will always sink to the bottom, mark this with a pen and add weight to the opposite side of the rim, keep adding weight until you can stop the wheel at any point and it will not spin by itself to a heavy point, congratulations! you've balanced your first wheel!

A smoother ride means you can push it that bit harder, so 0.1 seconds per lap should be achievable.

Perfectly balanced

#6 - A few of us here have long argued that 2 degree toe in rear uprights were absolutely essential on a mini … then Tony P showed up with zero toe, and he was fast, claiming that his extra speed was due to the tyres not working against themselves, but was his car still stable? Or did it wander? Well sometimes it did wander a hint, but it did get me thinking.

Recently Square or was it 3 Racing? Brought out a complete range of 0, 1, 2 and 3 degree toe in rear uprights, Tamiya added a 1.5 degree on their M03R just to complicate things … so which is the best toe setting of these? None of them.

We be dipping our toe in the water...	Your put your left toe-in, you put your right toe out...

Think about it, most of the race tracks run in a clockwise direction, so you make more right hand turns than left hand turns, so why not set your car up to run accordingly?

I've discovered through extensive testing that the best set up is to run the 2 degree toe in block on the left hand side as per usual, but also run a left hand side toe in block on the right hand side, so you're running 2 degrees toe in on the LHS and 2 degrees toe out on the right hand side.

I know it looks weird and the theory sounds even weirder, but this will give you a much quicker and tighter turning circle when turning right, and since most tracks have more right turns you will be quicker through each of these turns than the next guy.

This set-up should give you a 0.1 sec per right hand corner advantage, but will lose you 0.1 second per left hand corner. For example on my home track of Keilor there are 5x right hand turns and only 3x left hand turns, I will gain 0.5 on the right hand and lose 0.3 on the left hand, so 0.5 - 0.3 = 0.2 seconds. So I can only hope to gain 0.2 per lap...but that is still 0.2 better than the next guy!

#7 - Down on the upside? Okay, we've all seen motorbikes that run upside down shock absorbers, so why aren't we doing this on our r/c cars? I started experimenting with this a few years ago and to my surprise it works rather well.
The theory behind it is simple, an upside down shock reduces unsprung weight (which is a good thing!), it also lowers the centre of gravity as the fat end of the shock is closer to the ground. A lower centre of gravity provides for much better handling. An additional benefit is that it also creates a mild boost in spring rate, helping to reduce body roll, sway, dive, and acceleration squat. This mild boost in spring rate is also caused by the difference in the surface area above and below the piston. With greater surface area below the piston than above, more pressurized fluid (silicon oil) is in contact with this surface. This is why an inverted shock (in most cases) is better than a non-inverted.

It's SHOCKING!

I have found that on a faster more flowing circuit the mini is better with just the fronts upside down, while a tighter, twistier circuit requires all shocks to be inverted.

Experiment at your track to find which shock setup works best for you. Inverted shocks should be worth 0.2 seconds per lap.

#8 - I've saved the best for last, and this technique will gain you the most advantage of all!

Every other week there is a forum with people saying they dip their 540 or sport tuned motor in water, they wash it with brasso, they take it to a car junkyard and get the crane guy to pick it up with his electro magnet and zap the can - oops, wasn't supposed to mention that one!

I have now found THE definitive running in procedure for all of your sealed end bell motors, 540, sport tuned etc ...

Get more out of life	If you cant get at least 5 in, you're not trying!

Full of Mentos!	After the Alien autopsy I had a feeling the head would come in useful one day

When the bubbling dies down plug the motor directly into a 4 cell pack, the Mentos are loaded with nucleation sites (microscopic nooks and crannies) which help to form bubbles in the diet coke, this creates the violent fizzing effect which at the same time reacts with the nucleation sites on the copper brushes. The diet coke chemically bonds with the brushes, creating a protective barrier that prevents burning of the commutator, and enhances current flow from the brushes to the commutator. Enhanced current flow equals more power … more power equals more rpm.

And on tonights menu, Tamiya Sport-Tuned	Bubble, bubble, toil and trouble

You only need to do this once and it should gain you at least 2000rpm! Check out the photos.

Another 2000-3000rpm in a mini will give you at least another 1 second per lap advantage over your rivals.

A 4 cell pack is enough to bed the motor in	Before, not too bad, 21100 is a good starting point

Success! A whopping 24,100 rpm!

So there you have it, 8 of the most top secret ideas that I've been using on all of my race winning minis for the past few years. And now that it's April 1 I'm happy to let you all know them!

Good luck with your racing! But don't beat me!

Sorry for anyone who got 'sucked in' by this. It's our April Fools article for 2008. Please enjoy it for the amusement that we intended it to bring. And please don't try ANY of the things mentioned here!