Column

                                    by George Robinson

Having just been to the Offenbach Kart Show (see scintillating report elsewhere in this issue) it is clear that the Rotax MAX is still the TaG engine of choice in the karting world now and, I dare to say, for a long way into the future.

Yes, the new TaG engines have arrived but it is clear that these new units are destined for the elite and not the masses. The Rotax still ticks all the boxes and at a well controlled price. So many people talk about karting or motorsport as a whole being in crisis but this is just not true of the Rotax distributors in Europe and probably, for all I know, the world. The product continues to sell in significant numbers, the warranty scheme was a first in motor racing circles and a marketing masterstroke. Where else can you race for the thick end of a season knowing that your engine is effectively insured against mechanical defect? Although the warranty is of course conditional, it is nonetheless very effective in giving the end user peace of mind should there be any serious mechanical defect within the first six months of ownership. The only major exclusion to the scheme is piston seizure caused by operator error.

When the sealing agents were audited and appointed there were over forty approved dealers covering the UK and Ireland. This figure has dropped to the point that there are now a smaller, very dedicated list of agents that have become true specialists in the servicing and repair of MAX engines. There are no plans to significantly change the way in which these agents operate and they are expected to work to exacting standards and report all servicing that includes a reseal to the engines to JAG Engineering, the importers. Every system will have its critics but the controls in place for the Rotax classes have been fundamental to its success.

With the stability of the MAX range now assured, the factory are pressing on with the introduction of the DD2. The product has been around in RM1 form for a while but it is now available for any approved chassis manufacturer. This has been well covered in previous issues. However, plans are well advanced to start racing the DD2s in the UK in earnest. The Clay Pigeon shakedown meeting over the first weekend in March will see the DD2s take to the track in significant numbers. Chassis importers and manufacturers who have pledged their support include Gillard, HRS (CRG), Lucas Racing (MS), Modus (Haase), Walker Racing (Arrow) and a couple of others including Birel that hopefully will be there too. A grid of ten to a dozen is expected with some classy drivers in the seats. It is then proposed to run the class within the Super 1 Rotax championships this year. It is refreshing that new ideas can be accommodated at championship level. Last year saw the introduction of the 177kg class. Although this was adopted with very little notice at the start of the season and the grid was small, it did sustain throughout the season and finished the year with no significant drop in numbers. Registrations for the 177kg class this year already exceed those of 2006.

I very much expect the new DD2 initiative to have a similar level of success this year. The product is now very good and is significantly faster than a Senior MAX on both twisty and flowing circuits. The DD2 engine and accessories comes in a similar form to a regular MAX engine. The installation time is a little longer but relatively straightforward and so far I have built a Gillard and a Trulli with no major setbacks.

It is planned to run the DD2 on a slightly softer compound dry tyre. The performance, weight and four-wheel brakes are really begging for a little more grip. Vega has supplied a selection of compounds for evaluation, which is on-going at the moment. The tyre decision will be taken in time for the Clay Pigeon meeting. The rain tyre will be the trusty Vega W2.

Testing on the new engines has been very encouraging so far, the tractability and power delivery is much improved over the old RM1. There are only detail changes to the specification so existing RM1s would be relatively easy to upgrade. The DD2 kit comes complete with gear selector assembly, including paddle shift and engine mounts if required. It is also possible to fit a regular ICC rear bumper to all the karts I have seen if the DD2 is run with the 125 gearbox karts at some meetings.

Performance enhancement of any kart or engine can be an emotive subject. I do not agree with some of the claims that are made, however it has to be accepted that in a competitive environment everyone will look for any advantage to beat the opposition. First of all it has to be established that the advantage is achieved by legal means. I do not propose to dwell on the engine unit itself, so many experts have their own opinions on set-up and an equal number of competitors are happy to pay for it. What is the point in having the best of everything if it is not properly screwed together? The engine is only a small percentage of the whole package. The driver is certainly the most variable element, followed by the chassis, the way that chassis uses its tyres, weight, weight distribution, transmission, brakes and carburation, with the engine last but not least.

There are bound to be differences in engine performance, there are differences in Formula 1 from one weekend to the next. In karting where the slightest change can make such vast differences, the tendency of human nature is to blame the element we can do the least about, or know the least about. The best team managers and mechanics are always the ones who complain the least! Simple isn’t it!

I believe very few people ever check the most fundamental elements of set-up on their karts. For example, when did you last check that the engine’s crankshaft was parallel with the axle? OK, I bet it is ‘never!’ The easiest method with a MAX that has only one end of the crank exposed is to remove the engine from its mount, clamp it to the chassis and measure from the boltholes back to the axle. The assumption that the crankcase drillings and threads are parallel to the crank is safe. This dimension is generated in the factory and is more difficult to get wrong than right.

The engine mount is a different matter, who knows when and where the fixing holes were drilled and counter-bored. Some come with handy dimples as a drill guide but these are not necessarily supplied with the chassis. The only way to be sure is to do that simple measurement. Most people spend some time aligning the chain but few ever check that it is not running on one side of the sprocket or the other. If the sprocket is wearing on one side then there is a problem somewhere. This kind of drag can easily cost a horsepower. The condition of the transmission is of vital importance, not just from a reliability point of view. More of this next month.