Sunday, November 2, 2014

RWD Regulations Introduced.

There has been an introduction of RWD events in Japan that require a level of regulation for RWD drift.

Have a read if you have a Rear Wheel Drive gyro assisted drift chassis.

We all know that RWD has had an impact on the RC community in the search for realism a little more over the last year. Try both and there is a difference. Some might say a split, but I think embracing both will bring the hobby further and further. We have already seen the impact of low scrub C-Hub on 4wd also.

The main reason RWD and 4WD don't really play well together is speed differentiation between RWD and 4WD chassis.
The secondary reason is related to equalising the above speed issue.
      Tyre Compound choice and the effect of weight to gain traction / speed on the circuit surface.

In Japan, there a few venues that specialise in RWD. RC Oahu is one of them in the Tokyo area.
It is a very very small shop. You MUST use the single tyre they sell and there ends debate. This is true for Countersteer also.There are a large number of customers and culturally there is no issue with this regulation as battles are super tight.

You may have also seen RWD videos from Iroha as well.

The first reason you must use the supplied tyre is to protect the surface. Especially on carpet, but also on concrete will have issues.

If you use a Yokomo tyre that comes with the drift package, you will literally melt and rip the carpet from the huge grip that is created. I was told to change my tyres the first time I ever went to a Japanese indoor circuit, so I never thought about it as being a point of contention.

The softer the plastic / rubber, the more grip, more heat that's generated. On concrete the softer tyre compounds remain on the track, then hard compound tyres pick this up and no longer slide.

The second reason is to create a consistent speed so all people can battle at the same speed. Even real drift has this issue.

Recently weight has been added to RC RWD cars. On top of a full alloy chassis with heavy gearboxes, many users are adding an extra 500g of weight to get more traction.

Weight on the hubs, alloy rims, alloy brakes, weights inside the rim, weights inside the tyre, weights in the bumpers, weights in the diffuser. etc etc. 
What this has done has made driving the cars faster and faster, but the increased pressure on the surface is also more.

These RWD cars are now much faster than 4WD which typically have not changed the established tyre for surface.

The carpet circuit owners and RWD competitors have noticed the RWD cars turning the rears at higher speeds having an effect on the carpet and speeds increasing more and more in comps. We notice this at GCRC also where soft rubber is left on the surface of the track.

So for the next round of PRO-RC RWD there is a weight limit as well as the normal control tyre for RWD.  

PRO-RC Kobe.

Surface is painted concrete.

2WD Class

The regulation is simple

1. RWD Chassis : 1000g Limit
                         (1Kg) chassis excluding battery and drift style body.
2. Tyre: MST 830001CS-R Soft

3. Gyro: YES!

4WD Class

1. Tyre: Street Jam DT0019

2. Gyro: NO!

All Tyres are supplied with entry fee.

So if you choose the RWD path, you will notice the imbalance. I have both chassis, and the issues are known. I just respect the qualities of both and have fun finding similarly tuned chassis to run with. mixing both is not easy.

Managing the speed difference and tuning ability is a real challenge so I hope we can find a good balance for everyone.

At the moment I / we are having some great battles. The Rear Wheel Drives are getting better and better as the tuning is becoming more well known.

But as yet, the community has not yet self regulated. So maybe if we share some setups, we may be able to settle on a balance.

The sheer numbers in the Japanese community are starting to find that balance, but their products are not too readily available at your local hobby store.

Let me know what Surface / Tyre / Weight  you are running in the comments.



  1. Using mst cs-r/fr-f hard on painted concrete. I have mst wheel weights in rear. I also have 6 grams of weight each lower rear suspension arm. An additional 42 grams mounted to the rear damper mount. Chassis is an r16-fm rwd gold from Broadtech. No weights up front due to it already being front heavy.

  2. 1000g seems ridiculously light. I'd be inclined to say a WUN FR-D with their own line of upgrades would tip the scales at over 1000g's. I weighed my friends FR-D that he built using stock plastic drift package parts, with under 60g's of additional weight and it tipped the scales at around 1400g without battery.

    1. I agree. I can't read everything, Perhaps someone else can add. probably 1Kg of additional weight. haha


Got a question or a comment. It doesn't hurt to ask.