Category Archives: Rotax Max Column

George Robinson’s Rotax insight and technical tips from Karting magazine

The Max Column: July 2013

By: George Robinson

 

The future of British motorsport lies in the hands, or is delegated to, the Motor Sports Association or the MSA as we all know it.

 

As a general rule the average competitor only hears from their governing body when it is time to renew a licence or to be called to account following some misdemeanour during some competition or another.

 

The MSA is much maligned by all and sundry, but these same complainants are usually conspicuous by their absence when some work needs to be done for the good of all. If we seriously want to improve our position in motorsport as the largest single discipline that the MSA represents, then reward can only come from combined effort. We have to make a worthwhile contribution for the betterment of karting across all levels.

 

Last month I wrote about the introduction of the Micro Max class outside of MSA racing. This was not a side swipe at the governing body but a real attempt to introduce a level of professionalism to those that are at the introductory leisure end of the market.

 

We hear of provincial kart racing clubs that go out to promote themselves at supermarkets and shopping malls. Great; they may well interest a family or two to visit their circuit and even participate. This is great news as these people are genuinely new to the sport and needed to have their interest awoken. However there is a much easier and softer target out there that is almost totally ignored by the ‘proper racing public’. The leisure market in karting is huge and stuffed full of potential. These people are enthusiasts dammit! It is for this reason that the Micro Max is the perfect product to bring these potential customers out from their indoor Grand Prix events into mainstream racing and eventually MSA racing at club and national level. We desperately need to simplify the route into the most basic levels of motorsport, karting has to be the easiest and least expensive first step.

 

Karting has changed and I for one have been around long enough to remember the good old days. Yes we had fun, karts were lighter, more manoeuvrable and less expensive. They were also less well made, had no form of manufacturer’s warranty and in real terms were a lot more expensive to run and maintain. Club level racing has always been sporadically supported across the country. National level racing has grown as it has kept pace with demand. Yes the people that race nationally will spend more on their racing. In real terms nothing has changed. In 1966 the top driver that spent a fortune on his engines won the big races. In those days some of these guys arrived at the circuits in Rolls Royce or Bentleys dressed in real fur coats. Today the same level of competitive animal arrives at the circuit in a personal registration Audi, BMW or Mercedes. These people today may have a different agenda, but their ideals are the same. They are successful and they expect to remain so in whatever they do.

 

It is unfortunate that the world governing body went through a time of mismanagement that impacted upon karting at national level too much. When the industry needed to consolidate and look to a structured future, the CIK decreed that karting would be going to four-stroke power units within a couple of years. The project was not properly considered or managed. The date of introduction was delayed year on year. This created a period of great instability from which the international classes have never recovered.

 

In this period it gave the Rotax Max series of engines the opportunity to develop and grow without real opposition or competitor. The KF series of engines, which were designed around the Rotax ‘touch and go’ concept, were given too much latitude in design innovation. The result was stratospheric costs and shocking levels of unreliability. The classes are all but lost now and we see a resurgence of the 125 Gearbox classes. Indeed KZ1 has recently been adopted by the MSA as the Short Circuit British Championship category. I for one believe that this will produce a worthy British Champion and that should be from the elite.

 

Rotax Max was never intended to be that product. Some people have said how Rotax should be the championship class, and it is, within its own kind. Rotax Max is also affordable to more people and will always be well supported. There is a level within Rotax Max to suit everyone. The total novice can jump in a Max and feel his way into the sport with a machine that should last him for a season without significant expense. From the 177 class all the way down to Minimax the engine unit should not need to be serviced more than once a year. Yes there are regular service requirements but no more than checking the oil level in the family car is just good practice to avoid an expensive breakdown.

 

Recently I have had to look at a Senior Max engine that had been home built and carried no seal. The history of the engine was checked out with JAG in a matter of minutes and we were given the go-ahead to carry out the service including a full fiche check and then seal the engine. On investigation we found an appalling level of build quality. The end result of the service was an engine in good condition, legal, reliable and sealed. Also all the replacement parts are covered by the Rotax manufacturer’s warranty. This ten year-old engine is not under guarantee, just as if it were brand new. I am sure that much of the unreliability experienced by other engine brands is not an inherent design issue, but the inability of the builder to do the overhaul to a good enough standard.

The Max Column: June 2013

By: George Robinson

 

] Exciting things are happening in the world of Rotax Max at the moment. Since there has been significant growth in the interest for the DD2 class abroad, the service centres are receiving orders for engines greater than ever before in the UK. The DD2 has a great appeal for those experienced drivers who are looking for the next challenge which also carries the opportunity to race in Europe and possibly the Grand Finals, given enough speed and good fortune.

 

Micromax is also set to get started in the UK for the Cadet age group. This version of the Junior or Mini engine has been successful in other world markets including France, Germany, Spain, Portugal, Canada and the USA. Here in the UK the engine does not immediately concur with the MSA blueprint for a Cadet class. Unfortunate as that may be, the class has a very important role to play in encouraging this age group to progress from leisure karting into competition and eventually MSA racing.

According to National Karting Association figures, MSA licence holders account for a fraction of a percent of the paying public who enjoy a spell behind the wheel of a kart in any given year. It has to be a very worthwhile project to encourage as many of these enthusiasts as possible to progress to mainstream or should I say MSA racing?

 

Plans are being made to launch a serious assault on this project for 2014. Both Micromax and DD2 complement the existing range of Rotax Max engines. The Micromax could easily run for a couple of seasons without any need for service work. The engine is so under-stressed that the internal components are found to last almost indefinitely. Furthermore, the engine can be converted to Mini or Junior format in minutes. It is therefore extremely cost-effective and user-friendly.

 

Existing Junior or Mini engines are equally easy to convert to Micro, conversion components come as a kit of parts which a Service Centre could install on a while you wait basis if required.

 

The Micromax class has the blessing of a growing number of the major teams, clubs and circuits throughout the country. JAG Engineering have been cautious to introduce the class, but now have so many enquiries that going ahead is the only option.

 

The Micromax will fit directly onto any existing Cadet kart with a right hand engine mount. The mount itself has the same bolt spacing as a Comer and the exhaust is designed to go straight across the back of the kart parallel to the axle. With the single addition of an exhaust bracket the kart is ready to go.

 

The advantage of the fixed jet carburettor is ease of use and no necessity for the driver to take a hand off the steering wheel to keep the jet adjustment on song. Jetting is made simple by the use of a carburettor restrictor and very low compression that gives the engine an excellent band of power well suited to both the novice and the more experienced pilot.

 

At last the rain has stopped, or at least slowed down. The good news is that the lost entries over the winter are in recovery, indeed some of the smaller clubs are reporting a good level of growth in the Max classes. Particularly strong is Minimax. Over the past years there has been strong support for Cadets. This has often been referred to as the Hamilton effect. These Cadets have now come of age to move up, for them Minimax has been their choice.

 

Bearing in mind that the Max engine has been in circulation for over fifteen years it is remarkable that even those very early engines are still in circulation. I saw one recently that had still got its original seal and was being raced by a novice who was totally happy with it. I dare say that there have been gradual improvements in the engines over the years, but it is a great testament to the original concept that it has had such a long and successful career. A career that shows no sign of slowing down.

 

The Max concept was in part adopted by the CIK for the KF formulae, the part adopted missed some of the vital elements. The result, an unmitigated disaster for the sport as a whole. In terms of regulation the international governing body has taken a direction that cannot be described as a success for the good of the future of the sport. This unfortunate state of affairs has given the great stability of the Rotax classes a chance to shine and to grow at a rate that could never have been foreseen. The greatest responsibility we have is to ensure that we offer the karting enthusiast as fair and level playing field as is possible. This is also the responsibility of the governing body and their officials.

 

In July we will have a round of the Euromax Challenge at PFI. The circuit and their officials have successfully run a number of International events now so are well up to the task of hosting an RGMMC event on behalf of BRP Rotax. The DD2 class will be out in force as will the Seniors and Juniors. I am sure it will be a great event and attract a very full entry.

 

Any enquiries on Rotax related issues are always welcome, please contact info@jag-rotax.co.uk or myself directly on george@george-robinson.co.uk.

The Max Column: May 2013

By: George Robinson

 

In March JAG Engineering hosted their first Service Centre meeting which is an initiative that is recommended by BRP Rotax, the engine manufacturers.

[Dropcap] BRP stands for Bombardier Recreational Products and is now a stand-alone company that is related to Bombardier in name only. BRP produce a wide variety of products including SeaDoo, SkiDoo, CAN-AM as well as Johnson and Evinrude outboard motors. The Rotax brand has also been extremely well known in the motorcycle world.

In karting the famous 256 tandem twin redefined 250 Superkart racing at least thirty years ago, derivatives of this iconic power-unit still dominate the class to this day. In the mid-eighties the 100cc R100 engine broke cover, it was a new configuration of direct drive kart engine that again re-wrote the history books. No other engine manufacturer had developed the base unit since the introduction of early rotary valve engines in 1960. The Rotax models that followed the R100 dominated the market for at least ten years, the Italian manufacturers all created their own version of clone but in a straight fight to the flag it was still predominantly the Rotax that got there first. In 1997 the Max went into production and it was soon in short supply as the hungry market adopted the product. Once again Rotax had broken the mould with the self-start and clutch concept that has now been universally copied.

BRP were clever to recognise that the karting public had changed and changed forever. The new age karter was not someone who was a purist that was happy to run along to bump start his machine. Nor was this new age karter happy to watch the racing from the side lines having seized his engine because the mixture on his carburettor was a tweak too lean!

 

Occasionally we do not see the value in the innovation of a new product and of course we now have a customer base that knows nothing of how karting was in its infancy. The old guard, self included, need to move on and put the past behind us. Without modern innovation and development we could not continue with racing and leisure karting as we know it today. The leisure side of the sport is every bit as important as the racing. The vast majority of the Service Centre personnel who attended our recent meeting have been in the sport for many years and most have been drivers as well. The background of these guys is in the passion for the sport, but we all need to remember that we are now dealing with a modern product delivered by a thoroughly professional and modern company. Today it seems perfectly normal to expect a warranty with your new or refurbished engine, the customer demand is not so much “Is there a warranty?” as “How long and how good?”. This is in fact remarkable in that it is a product used for racing purposes, and that historically the only thing about a kart engine that you could guarantee was that it would definitely blow up and the only question was how badly! For today’s market the warranty scheme was a marketing masterpiece.

 

A BRP innovation came in the shape of the RM1 kart and engine. This has evolved into an engine-only product, the DD2. This is a unique concept with similar engine design to the Senior Max but driving a two speed gearbox through a wet centrifugal clutch. The final drive is through the gearbox directly onto the axle. The end result is a powerful engine with no chain drive. It is clean, safe and fast.

 

A few years ago the DD2 raced at Super1 level and received a reasonable level of interest, however it was probably too soon to expect the class to be really well accepted and the 177 Senior Max class was gaining in popularity. In the intervening years the DD2 has evolved into a really exciting concept and is now popular in the EuroMax and BNL Championships. Apart from racing, the DD2 is an exhilarating leisure drive for the born-again karter. Many of the Service Centres are supporting a launch of the DD2, so if you want to find out more or even fancy having a go either contact us at JAG or your friendly local Service Centre.

 

In Florida this winter there has been much better weather than we have been enduring back in Blighty. Some top British drivers made the trip to get some winter sun and enjoy some quality racing. However it was Charlie Eastwood who stole the show for Ireland, the current World Finals winner proving that the Portuguese victory was no flash in the pan. Charlie who has sometimes been dogged by bad luck has really found his place now, he has matured as a driver and has developed the ability to convert the speed that he has had for some time into results.

 

On the technical front this month are a few short words on the new crankcases that are now available. Following completely unfounded rumour that the new cases were better, faster, slower or painted pink, they have arrived and are very good. That is to say that small areas of design have been improved but the performance difference is non-existent. You will be just as competitive with the original cases as the new and there is no need to buy into an expensive rebuild of the existing engine or indeed to buy new. Fortunately new sales are as strong as ever at this time of year and residual values of good used units are also strong. As ever, beware of the internet adverts that promise the world for the price of a bag of sweets. Cheap can be a bargain, but you can also buy into a bag of trouble more than you bargained for.

 

The first watchword is to check that the engine is sealed. If so then a quick call to JAG or a Service Centre will reveal a good deal of the engine’s history. This is a bit like a current MOT certificate on an old car. Yes it was roadworthy then but how is it now? At least with a Max, karting is a relatively small world and the chances are that a recently sealed unit will have the expertise of the Service Centre built in. When a Service Centre puts its stamp in the book it is their advertisement to encourage the customer to come back to them in the future. Furthermore, a Service Centre will probably offer to give an engine a free health check providing that they do not have to break the seal. A lot can be deduced from a look over the engine as to how much time it has done and whether a deeper look inside would be advisable.

 

JAG may be contacted at info@jag-rotax.co.uk or myself at george@george-robinson.co.uk

Buying a Used Engine

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The winter has been a busy one in the world of Rotax Max with the shows to attend and work with the Service centres to further improve the customer’s lot. By the time this is in print we will have held a Service Centre meeting, the vast majority of Centres have accepted the invitation. This will give both us at JAG and the Rotax factory a very good understanding of the market and how the customers’ needs vary across the country.

I believe this type of forum to be vitally important to the continued improvement of the service that is offered and ensures that the customer gets fair and even handed service no matter which centre he uses.

The Rotax warranty scheme is well established and continues to give customers of new and rebuilt engines a degree of assurance which is unique in the karting world today. The current engine units have no particular weaknesses and this can be attributed to the invaluable feedback which can only be achieved when the warranty system works as efficiently as it does.

The new and long awaited crank cases are now in stock, they have been delivered on new engines and are also available as spare parts. I have spoken to a number of service centres and they report that there is no change in performance over the old type. The new cases are very well finished and take advantage of modern casting and machining methods. There are some detail improvements which not only save material, but also do not compromise stiffness and integrity of the finished product. I particularly like the webbing from below the cylinder studs down around the main bearing pockets and then splaying out to give extra rigidity to the engine mounting bolts.

Recently we have seen a lot of carburettors which are not in good shape. I am amazed that people will spend a significant budget on their equipment and just getting to meetings and then overlook this most vital part of the performance jigsaw. Where the carb is concerned it is impossible for it to be too clean! When not in use it should be drained, cleaned and put into a self-seal plastic bag. A general spray of a moisture inhibitor like WD40 would not go amiss either. I believe we are fortunate to have remained with the carburettor specifications that have been in force here for many years. As many of you will know there are a new set of regulations in the RMC which is effectively the official Rotax International rules. For a start they outlaw the 12.5 venturi and have other slow jet and float regulations that differ from our own. While this change would have little effect on the big teams and the drivers that race nationally, it would be an unnecessary expense for the club driver on a tight budget.

We must never take our eyes off the fact that the club racer that has just one kart and engine, is the bedrock of the sport. There is a burgeoning customer base in the Cadet classes which need to feel confident to move on into the Junior classes without the fear of escalating prices. Whatever class these guys choose it needs to be attainable at entry level. The Minimax has become a lot more user friendly since the introduction of the carburettor slide restrictor. The club class is now growing strongly. Used outfits are readily available for little more than the re-sale value of their Honda Cadet equipment. A chassis that has spent its life in Minimax hands will have a greater life expectancy than a kart which has been harnessed to a Senior or 177 pilot!

With the JAG records department now permanently staffed there is a mine of information available to give the history on any sealed engine offered for sale. While this is not a guarantee of its current condition, it does give the prospective purchaser a feel good factor of the care that the engine has received. A bit like a used car, a used engine will betray poor maintenance if you look a little deeper into its appearance. Items to watch for are condition age and type of radiator. All three radiators are fit for purpose. These days a black radiator is a bit of a sales stigma when fitted to a Senior engine, it is however still widely accepted in Junior or Mini format. The “Black Rad” is gradually dying out so an engine with an old one that has had a hundred hits would be a good starting point to negotiate the price down a bit! In round terms a new silver radiator will set you back £200 so imagine what the engine might be worth without one? If you are buying an engine on its own do beware that you are receiving the accessories you expect. This is one advantage of buying a used outfit complete, at least you definitely have all the bits!

The same goes for the exhaust system, has it been welded? Not in itself a disaster but it does suggest that it has had a life… before death! Once again a new pipe will set you back the approximate magic figure of £200 so another pawn for negotiation.

There are plenty of really sound used outfits on the market for under £2000 complete. By the same token it is hard to find a gem for less than £1500. The bonus is that for the beginner in Minimax these engines are unlikely to need any major service work assuming you have bought with confidence that the unit and its ancillaries are in good order.

The Max Column: March 2013

By: George Robinson

 

The appalling weather has not deterred the hardy karting participants from braving wind, snow, floods and rain from going out this winter and apparently enjoying themselves.

I have heard from a lot of Max owners who want to know about jetting and winter maintenance, only a few have been disappointed by cancelled events and closed circuits.

Thinking that we had largely escaped the frost-damaged engines that have been left without antifreeze, unfortunately I have heard of a few in just the past week. I believe that these engines may have escaped while kept in a garage which; while unheated, may have had enough borrowed warmth and lack of draft to save its unprotected water jacket.

The unsuspecting owner loads up his pride and joy into a van the night before and arrives at the track the following morning with a split cylinder and potential internal damage to the water pump and seals. I have even seen one with the core plug in the crankcases dislodged to the point where it came out as soon as the engine was started. If you are not sure just give the radiator fluid the lick test, if it tastes like it is probably killing you, then it has antifreeze and the engine will be fine, you on the other hand may ingest glycol which can be fatal. The easy way to change the fluid is to release the bottom hose remove the radiator cap and allow it to drain into a bucket. Do not discharge the fluid onto the ground as it will not dry, destroys all living beings and tarmac. It is also more slippery than ice, so please do not think it is the quick answer to your mother in law issues, you read it here so will not benefit from your inheritance when behind bars!

Fresh antifreeze is better for the protection of the internal components of your engine as well. It is easy to see those engines that have been well maintained, the water jacket is clean and mildly stained by the coolant.

An area that we have not touched on for a long time is the balance gears. There are three types of gears that have been fitted since the Max engine came into being 15 years ago. The original type being the plastic type. These gears are still perfectly good, reliable and available as a spare part.

The plastic gears do however require some special care when fitting. It is most important not to force the gears onto the splines. To be sure that there is enough clearance for them to slide on easily, the correct method is to gently warm them with a heat gun or hair dryer. Fit the crank gear first with the protruding boss on the outside, or flat side first. Line up the moulded in groove in the gear to the mark on the end of the crank, this can then be lined up with the triangular V in the casting of the crankcase, which can be found at about 11 o’clock to the crank centreline. This is also the position of piston at Top Dead Centre. If you are able to stand the engine on a horizontal surface without its mount then the cylinder should be in the vertical position. This will facilitate the fitment of the second gear onto the balance shaft. Once again warm the gear and it should slide easily into lace the end of the shaft is marked and with the engine vertical this mark should be at 12 o’clock. Before fitting the clips, as a double check, you can rotate the crank anti-clockwise, the marks on the two plastic gears should line up. Always use new gear clips and be sure not to stretch them when fitting. If necessary fit a new gear cover gasket, be sure that the two screws with the copper washers are in the correct positions and refill with oil. In this type of gear cluster 50cc is the recommended level, a little less will be adequate at 35-40cc with less risk of oil being expelled through the breather. If you use less than the recommended fill quantity you must check the level regularly.

Steel gears were introduced a few years ago; from memory I think it was 2008. These were supplied to complement the steel clutch, which was introduced at the same time. It is even more important with these to be sure that the retaining clips are the latest type and in good condition. The gears and clips are extremely reliable but poor or incorrect fitment can cause trouble. Backlash or wear on the splines needs attention, in extreme cases this can lead to poor performance and a noisy drive train. Actual failure of the gears is extremely rare.

The steel gear cluster has a smaller displacement than the plastic so more oil is required the recommended fill level is 100cc but I know some drivers that have reduced this to only 50cc. Once again do be sure to check the oil regularly and in the case of the steel gears be sure that the oil is not too black. Black oil denotes the beginning of wear and should be investigated.

There is a third gear type that is the current steel variety. These have a different profile to the earlier type and wider teeth. There is no known performance difference between the gears but they must be fitted in pairs. Steel gears may be mated to an old type clutch but not the other way around. There are still a lot of old type clutches in use, particularly in the leisure market, the parts are still available and have no particular vices until worn out! If the clutch shoes become too loose on the fulcrum pins then a by-product of this problem is broken balance gears.

All genuine new delivery front sprockets will be marked ROTAX. However it is not a fiche requirement that this marking is present. For many years the sprocket was unmarked and their extraordinary durability means that there are still quantities of unmarked examples still in use today.

New Carburettor regulations applied in the Rotax Max Challenge and some European countries do not apply here in the UK or Ireland. We are obliged to give six months notice of changes to regulations unless it is a “force majeure” situation. Accordingly, the earliest that we could apply any new regulations would be January 2014.

The Max Column: February 2013

By: George Robinson

 

In the depth of winter when there is ice and snow all around us time in a kart is certainly the place for the hardy or unwise.

I have decided therefore to dedicate this month’s column to the technical aspect of the Max classes.

 

I believe that this column appeals more to those fairly new to the sport or those that have an open mind to sharing experience with a view to gleaning ideas from each other. There is certainly an area of performance, which is a constant buzz in the paddock at most race meetings.

 

Release is the modern word for it. Bottom end was one of the old words, either way this phenomenon is certainly the source of frustration to mechanics, managers, parents and drivers. The Rotax Max classes have attracted a completely new type of clientele to karting. Gone is the purist enthusiast of yesteryear. However many of the influential people in the sport are of that era.

 

Technically the poor corner exit speed can be attributed in many ways. Karts today are 50% heavier with the same or lower power output than fifteen years ago. The power band is narrower with lower maximum RPM. This means that a smaller rear sprocket is used in order to achieve the straight-line speed; the payoff for this is compromised corner exit speed. The chassis design has not changed very much at all in the past twenty years but the power units have evolved out of all recognition. The Rotax “touch and go” concept has swept the world and swept aside all others, this is not without its difficulties and a greater understanding of how a chassis works is required in order to get the best out of it.

 

Most engine builders will maximise the low and mid range power. This is the performance most easily felt by the driver. The max range of engines are strong in this area, they were never designed as high revving engines. The Max relies on its torque to deliver the best level of power possible through a single gear ratio. To achieve the best lap time a good basic rule is to gear the kart to compromise the slowest corner. This does not make for the most rewarding of driving experiences, unless of course you are the one overcoming the difficulties of driving fast and are the person in front driving away from your rivals!

 

Let us assume that the engine is performing correctly and is fitted with the correct jet and front sprocket. The kart is sluggish off the corners and others seem to be able to create too great a gap for you to get on terms to set up a clean overtaking manoeuvre.

 

If the kart is correctly set up then there is only the driver to consider. Karting is no different to any other sport; the best make it look so easy! It may seem essential to drive on or near your limit in order to keep up, it takes a depth of character to try slowing everything down, concentrating on taking every corner as neatly with the minimum of slide or squealing tyres. It is probably overstating the case to say that tyres should only protest under heavy braking. However it would be a good starting point, if the tyres squeal in mid corner, you are asking them to grip beyond their capabilities. This is wasted energy. Just as you are working your socks off to keep up, you too are wasting energy. In mid corner it is vitally important for the kart to be running freely. If all four wheels are equally weighted on the ground it is extremely difficult for the kart to move forwards, you all know this from when you try to change position on the dummy grid, or move off on full lock to avoid a non-starting kart. This is exactly what happens when a kart is incorrectly positioned in mid corner, you are asking too much of the engine and will exit the corner less quickly than if you had taken the corner correctly. The best drivers hardly seem to move the steering wheel; this is because they know that any movement slows them down. The best way to describe this is balance. The whole process of taking a corner well is to get the balance right well before the corner. Of course the idea is to complete the lap as quickly as possible. This does not mean to say that you have to be the last of the late brakers. Get the speed down to a level where you know that the kart will remain in control and you can apply the throttle gently and as early as possible. A little throttle early is much more valuable than all of it when the tyres are still screaming in protest.

 

So now that the driver is perfect (!), let us look at the chassis preparation issues that can lead to the engine getting the blame. Probably one common and often overlooked problem is the brake binding in the corners. The brake may seem to be fine when the Kart is on its trolley. On the circuit it is another matter, the brake can bind very easily when the axle flexes in a corner if the pads are too close to the disc. A piston could be sticking when hot, the brake overheating will in itself cause the pads not to return fully, braking efficiency is lost and the problems compound themselves. The axle moving in the bearings will also cause the disc to load up on the outside pad causing occasional drag. The best braking is done as hard as possible and for the shortest possible time. Maximum speed is maintained for as long as possible followed by maximum retardation, followed by off the brake completely by mid corner at the latest.

 

Alignment of the chain and sprocket would seem to be so simple. Have you checked to relative thickness of the front and rear sprocket? Very few are the same, usually the rear sprocket is considerably thicker than the front. Lining them up with a straight edge or some versions of laser is thereby flawed! Just food for thought…

 

Happy New Year !

The Max Column: January 2013

By: George Robinson

 

The Rotax Grand Finals were contested during the last week in November. Drivers from the JAG Distribution areas of the British Isles and Ireland dominated the event taking home the Nations Cup for the first time for several years.

Last year’s Senior class winner won again with two significant differences. This year it was in the DD2 class that he triumphed and secondly he was racing under the flag of his new home Canada. Ben Cooper is the name taking his World title wins up to three, equalled only by Cristiano Morgado of South Africa who kept the Brits at bay to win DD2 Masters.

Charlie Eastwood qualified and raced well to clinch the Senior class. Charlie races with a Motorsport Ireland licence having qualified for the Grand Finals through the Super 1 series.

In the Junior class it was Harry Webb who took the honours after a spirited drive up through the final grid to take a popular win. There were great drives from many of our others drivers that all played a part in our Nations Cup win. The circuit at Portimao gained everyone’s appreciation even if the weather did not live up to expectations all of the time at least it was dry for the Finals. The Grand Finals are scheduled to be held in New Orleans next year, America for the first time. I know that the Rotax distributors for the USA are already making plans for a sparkling event although final confirmation of the date has yet to be ratified by the CIK.

Kartmania was a good show for us with plenty of people coming onto the stand during both of the days, you can always tell that the day has gone well when the closing time comes sooner than you think. The Kart Boot sale was also well supported and many reported a very strong level of business. The venue at the Silverstone Wing is impressive and looks set to continue next year. I am reliably informed that visitor parking will be very much improved.

The rumour mill has been grinding away busily. There has been much speculation about the specification of carburettors, it is probable that the international spec will change slightly but I can assure you that the UK and Ireland regulations will remain as they are. We will continue to allow both 8.5 and 12.5 Venturis. There will be no change either to the floats and slow jets allowed. Just make sure that you have the right configuration. By the same token both K27 and K98 needles will remain legal for use in our distribution area.

Another rumour concerns the exhaust, there are no plans to outlaw the old type exhaust. There is still a high proportion of the original pipes in use and many of them are still in a perfectly serviceable condition. Until these numbers reduce significantly there is no need to ban these exhausts while they are doing their job satisfactorily at club and  Championship level. It is only when there is a rarity value attached to components that prices can escalate very rapidly and a phasing out period is the only fair course of action.

There has been much speculation over the introduction of new crankcases. This has not been altogether positive for the stability of the market. We have a six month notice of intent agreement with the MSA which is there to protect the end user from hastily introduced changes to specification. There are circumstances where these guidelines are impossible to adhere to when a component suddenly becomes obsolete for example. However when the MSA were informed of the forthcoming change to the crankcase moulds, it was very quickly in the public domain. As I write this we know that new cases will be available in the New Year but there are no new cases or engines fitted with the new product in the UK at present. There was rumour that the engines at the Grand Finals would have the new cases, this was not the case. I have seen an example of the new crankcases and they look very similar to the old type. There will be a clutch cover coming soon, this can be fitted to both old and new type crankcases alike. There are no plans at present to make the clutch cover a mandatory fitment.

There have been very few complaints regarding oil or grease on the clutch since the introduction of the crankshaft O ring. It is most important that you do not over-grease the needle bearing. The best method is to install the rear thrust washer, O ring and bearing completely dry. Smear a very small amount of high melting point lithium grease on the inside of the sprocket bore and complete the installation. In this way any excess grease should be squeezed out of the clutch bore where it can do no harm. If the clutch drum is too hard to push onto the shaft, the most likely cause is that the big 28mm sprocket retaining nut is just too tight and has in fact minutely reduced the inside bore of the sprocket. Now that the steel type clutch has been in use for a couple of years it is worth checking or asking you friendly Service Centre to measure it for you. While the clutch unit is now very reliable it is possible that the segments have worn down to be outside the minimum wear tolerance. If so it means that the unit has done a lot of work in the past and the replacement unit has to be a worthwhile investment.

All that remains is to wish everyone a very happy and peaceful Christmas and all the best for the forthcoming year.