Tamiya TA05-R static problems – Part III

OK, here is my final version of the static strap.

Now using eyelets which are crimped and soldered onto the wire. Makes the setup very easy to fit and remove, also the assembly has no effect on the tweak or integrity of the chassis.


See previous posts on this blog here and here.

Tamiya TA05-R static problems – Part II

Here is my interpretation of the KO static fix mentioned earlier.


I hope you can make it out. Basically I have fitted cone washers upside down in the countersunk holes, with round head screws through them to grip the wire. The wire is some thin black bell wire from Maplin (bought a long time ago), which has had the ends tinned to stop them breaking up (untinned wires were damaged by the screw thread). The cone washers are by Jet Racing (#JE-43P). Unfortunately these are not available in Tamiya blue, I used some purple ones I had lying around. The screws are Much-More stainless steel ones, M3x12mm round head (#MSR-312). Jet and Much-More products are available in the UK through www.muchmoreracing.com.

Tamiya TA05-R static problems

Tamiya recently released a statement about static electricity building up in the TA05-R chassis, and potentially causing problems with your metal-geared servo – full statement here.

This is something I had never, ever heard of happening with another car, but I do think I have experienced the phenomenon myself. Mid-race the servo “lost” it’s neutral position and the car veered off the track, but switching off and on again caused it to go back to normal. It’s only happened once but obviously I’d rather not have it happen again.

Tamiya’s own suggestion is to fit the #53893 optional carbon moulded tub, which is conductive, but also quite expensive compared to the plastic tub, and stiffer which will affect the handling a little.

But now KO Propo have published their own solution to the problem.


First step is to take a 10cm length of fine gauge wire (approximately 1-2mm, KO recommend their own antenna wire), and strip the ends.


Second step is to attach the cable to the screws on the centre bulkhead and the front steering post. This should apparently give the static a route to discharge that avoids the servo.

KO appear to have simply screwed the wire in place. What I have also seen, and what may be neater in terms of assembly, is to solder the wire onto the screw heads.

Original instructions here.

Source: www.tamiya.com, www.kopropo.co.jp

Tamiya TA05-R Build Tips

For what it’s worth here are a few brief tips for building the TA05-R…

Before you start – get a replacement hex screw set. Phillips screws are not up to the job on this car – see my previous blog entry http://www.sosidge.com/2007/04/18/hex-screw-kit-for-the-tamiya-ta05-r/

Also make sure you have good quality tools to hand, Tamiya supply a couple of Allen keys which are useless, get hold of some quality hex drivers (1.5mm and 2mm required). Tamiya’s long 2.5mm Allen key for the motor screws is essential though. Also, Tamiya’s optional Turnbuckle Wrench #53602 is much better than the stamped wrench in the kit which wears the turnbuckles heavily. If money is not an issue you might like to try Tamiya’s 5mm Adjuster Wrench #53858 which should make it easier to thread the turnbuckles into the ball ends. The classic Tamiya box wrench is fine though, I’ve never seen the point in the expensive individual nut drivers.

Tighten screws evenly in a star pattern to limit stresses on the parts, also don’t overtighten to prevent damage. Carefully apply threadlock to the tip of the thread in metal-to-metal fittings, don’t make the mistake I made with the car and let too much threadlock seep onto the screw heads, locking them tight!

I always shim my cars to remove excess play in parts. Tamiya do supply some 3mm shims for the suspension, however a pack of 5mm shims (Tamiya #53587, other brands available) and an extra pack of 3mm shims (#53585) may also come in handy. Parts must still move freely under their own weight once shimmed.

Step 2 – crush the diff spring MA16 with pliers a few times before assembly, not only does it bed the spring in, it also makes it easier to assemble.

With the silicone ball diff grease, a little goes a long way, no need to pack everything with it, just make sure there is enough to lightly cover the balls and plates.

4x MA29 shims may be a little tight when assembled, I am using 1x on each side which seems freer without excessive play.

Step 4 – I replaced the MA32 spur gear with a Kawada 48dp item with 76 teeth. I’m told a 78 is the biggest 48dp gear that will fit.

Step 7 – the MB2 droop screw setting is just a guide, personally I run my car with more droop than suggested all round, ie less thread below the arm.

Step 8 – the supplied 3mm shims can be used here, and on all the suspension hinge pins if required to stop excessive fore/aft movement.

Step 9 – in my opinion the driveshaft joints are the most important part to threadlock on the car – if they come loose mid-race you  are done for.

Step 10 – some 5mm shims will take out play on the rear axles. Also, a recommended option part to fit here is Tamiya #53891 Bearing Spacer – which should reduce side-load on the 950 bearings and prolong their life.

Take care when drilling out the grub screw retaining hole in the hub. Once drilled, make sure that the hinge pin hole is clean as well as otherwise the pin can get a bit stuck which is awkward for disassembly.

Step 11 – quick maintenance tip. I find that the easiest way to adjust the diff setting is to slide the hinge pin out of the hub and lift the whole axle clear. I mark the suspension arm that the diff screw is on with a silver paint marker to I know which side to take off. In fact I mark many parts on the car including wheels and shocks so that they go back in the same place they came from.

Step 20 – note that K7 is directional, the side with the dimple on is the side that MB3 and MB13 fit to.

Some 5mm shims between K2 and K4 will help reduce play. Hold them in place with a dab of grease during assembly.

Step 23 – ensure that the stabiliser/anti-roll bar drop links do not rub the driveshafts at the front when assembled. Also make sure they move freely, the grub screws MB4 should not touch the bar, they are simply there to stop it moving up and down.

Step 28 – take plenty of time to carefully trim your servo ears to make sure it is a good fit in the chassis. Ditto when trimming the servo saver. The servo must be secure and correctly aligned, as well as moving freely from lock to lock.

Step 29 – fitting the pinion can be tricky depending on the manufacturer. I have found that RW Racing gears are the easiest to use as they have a recess in the face.. Some other gears need the motor to be loosened or even removed for pinion changes.

All done! – All in all an easy build with the exception of fitting the servo which took ages to get right.

A few pics of the Tamiya TA05-R – Part II


Close up of the centre of the drivetrain. Switched from the Tamiya 0.4 module spur to a Kawada 76T 48dp spur – I’m told that the largest you can fit is a 78T. Pinion is RW Racing steel jobbie, these are well suited to the car as the design means that they can be put on the motor without having to loosen or remove it. Some other pinions need more messing about with the motor screws to get on. Otherwise everything is a nice snug fit. Aluminium bulkhead top is unique to the TA05-R and very “bling”!


Front suspension. Kit is supplied with “Milky Yellow” springs, I have gone to the standard Tamiya option springs (#53440 for the set), simply because they are easier to tell apart! The car also comes with arguably the nicest version of TRF shocks yet.


Underside of the chassis. One slight disappointment for me is that the moulded chassis is not as true and tweak-free as I have become accustomed to with woven plate carbon chassis. Also, the rounded edges make it a shade trickier to measure ride height. However, this is not really an issue when you run the car. At our track the extra flex is a benefit, generating grip to keep the car planted. Also the moulded chassis is dirt cheap to replace – UK price is about £10, whereas most carbon chassis go for £50 or more! I already picked up a spare after I messed up with the threadlock and ended up having to cut slots in a few screws – fortunately the original chassis was only slightly affected so it is staying on for the time being.


Rear suspension – car comes with the optional Lightweight suspension setup from some of the TB Evo and TRF cars, seems to work well! One of the things about Tamiya is that they offer so many different suspension parts that you can get totally confused about what the best setup is. To my mind if the car drives well that is 99% of the battle won, changing parts on a whim makes for a pretty costly hobby. My only criticism of the LW suspension is that the plastic rear hub mouldings are made of a slightly softer material than the arms, proabbly to absorb impacts, but there is a shade too much play in the wheel axle. A little 5mm shim helps but is not the perfect solution. Tamiya alloy hubs are available but are expensive and have less toe in so you would need to change setup to compensate.


Last pic for now is trying to get a view of the steering setup. Pretty tight fit and the high-torque servo saver needs a lot of careful trimming to get right. More annoying is that the servo case needs to have an ear cut off to fit the car, again take time over this to get it as low as possible without weakening the ear. I also fitted some thin sticky back foam on the chassis to give the servo a little bit more support.

A few pics of the Tamiya TA05-R

Sun sort of came out this afternoon so I though I would take advantage and get the camera out…


Shell is a Protoform Mazdaspeed 6. Custom paint job courtesy of Tamiya PS-1 rattlecan. Wheels are JC Ascari (I think). Note how I haven’t cut the slots in the rear wing. This is because I couldn’t be arsed.


View of the chassis. Spiked tyres may surprise some of you – they are Schumacher minipins, used on the slippy floor tracks that are quite common still at UK clubs. Grip is low, which is one of the reasons the TA05 works so well, the chassis has that little bit of flex which sticks the car to the ground. Last week the top 2 qualifiers were TA05’s.


The view from the top. After much fiddling the electronics have gone in very snugly. Setup is IB4200 cells, Futaba S9451 servo, Futaba R133F receiver, Keyence Rapida Pro Metallic Blue ESC and Integy “Blue Atlas” 19T motor. The blue theme is a happy coincidence, most of this stuff used to be in my Kyosho which was red alloy!

I did have to remove the Euro connectors from the Keyence to get it to fit, at the time I was a bit unsure about this but actually it has worked out and given a very neat install.

Hex screw kit for the Tamiya TA05-R

I’m now the proud owner of the new limited edition Tamiya TA05-R touring chassis – pics and more details to follow. In brief I am really impressed and the car is fast.

In the meantime, I recommend any owner get a hex screw kit before they even start the build to replace the standard Phillips head machine screws. To cut a long story short they aren’t up to the job for this car. What follows is a list of the sizes you need.

29x M3x8mm Round Head
8x M3x10mm Round Head
1x M3x12mm Round Head
19x M3x8mm Flat Head
14x M3x10mm Flat Head
6x M3x12mm Flat Head
1x M3x23mm Flat Head

Notes: M3x23mm is probably a diffificult size to find. An M3x20mm is what I used, it is just about long enough to fit the motor mount with threadlock. An M3x25mm would be better. M3x30mm or longer would probably also fit but stick out at the top.

I used stainless steel screws available through Much-More UK – www.muchmoreracing.com – plus a couple of spares from the pit box. Total cost around £20.

Included in the car are some “flat” round head screws for the spur gear and servo mount that are a Phillips head. I wouldn’t recommend changing them as they have a special low profile head and a standard head may stick out.

Finally, threadlock all metal-to-metal fittings, trust me when I say that they do work loose if left clean.

That’s all for now!