December 3, 2025

Chassis Focus – Simon Kurzbuch (Mugen Seiki)

Chassis: Mugen Seiki MRX7
Engine: Ielasi Tuned Pista
Exhaust: Ielasi Tuned EFRA 2196
Radio: Futaba 10PX
Servos (Steering/Throttle): Futaba Ct702
Body: Xtreme Hyper
Tires (handout): Matrix
Fuel (handout): Energy

Notes – With the MRX7 only just recently released, Simon is running it pretty much straight out of the box.  Using a Hiro Seiko screw set in building the car, the only modification for the World Championship is a cut in the front of the radio tray for extra flex which Simon said made a quite noticeable different to the set-up.  On the clutch Simon is using a spring from Italian specialist BM Clutch Spring. 

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December 3, 2025

Catanzani takes close opening qualifier as Kurzbuch finds form in Chile

Serpent’s Andrea Catanzani has taken the opening qualifier at the IFMAR 1:8 Onroad World Championship in Chile, this morning’s first of the six schedule rounds a close encounter as Mugen Seiki’s Simon Kurzbuch found his form after a below par seeding yesterday.  With a first lap error from Catanzani, it was 2019 World Champion Shoki Takahata who set the early pace but soon it was Top Seed Catanzani who was back at the top of the timing screens but all the while Kurzbuch was executing a strong run getting to within 0.156 of a second of the Italian, the two drivers the only ones to run 23-laps of the CACH track over the 7-minutes.  The star of yesterday’s seeding, Xray’s Maxime Ripoll would complete the Top 3 despite the French driver having a poor pit exit after his fuel stop, his car bouncing off the steel barrier.  Capricorn’s Toni Gruber would open with a P4 run after a driver error dropped Takahata back to P5 with the Capricorn of Thilo Diekman completing the Top 6.

‘7-minutes is very long with 1:8 but yes that was a good run’, that was Catazani’s reaction after topping Q1.  The 20-year-old continued, ‘I made one mistake on the first lap so I half a second.  In the sweeper I hit the insider (track marker) and then the lap later I was a little bit nervous but then I settled in to my pace and it was really good.  We tried something new (set-up) this morning and it was really good but now we need to practice a little bit on the refuelling because we lost time there, but we are fast so I am happy.’

With a spring back in his step following his P2 run, Kurzbuch said, ‘It was a good first run, pity we couldn’t get it as it was quite close.’  Having struggled yesterday and opted to full rebuilt his MRX7 for Q1, he said, ‘the car is working better, still a bit understeering so we can improve that a little bit, but yes I think we are in the game now.’  Asked if they found any issues during the car rebuilt that would have cause his lack of pace yesterday, the Swiss driver replied, ‘No we found nothing wrong but we built up the car from scratch, everything new, everything fresh, so maybe just sometimes all this helps.’  On the track conditions and whether the morning or afternoon is better for him, the 2015 World Champion said, ‘ Normally the morning is better for me’.

Disappointed with his own driving performance in Q1, Ripoll explained, ‘ I lost a bit of time getting on to the pace but its OK, P3 it is one good qualification already.’  The teenager continued, ‘We also lost a bit of time on the refuelling, my pit exit was horrible.  I lost 1-second on Simon.  My pace was not super good but I know when the track will be hotter my car will be more stable so.  For me now (morning) is the worst condition but I know it will get better but for the next one I also need to drive better.’

Describing his P4 as an ‘OK start’, Gruber explained, ‘The car felt really good in the afternoon yesterday after some changes but with the two sides to this track, the morning and the afternoon, the now now feels a little bit slower than the afternoon yesterday.  I think we have the set-up for the afternoon and not the morning but it’s nearly both.  Mostly in work in the afternoon but also in the morning it is not bad but not the best performance. But you know the final is in the afternoon so it better it work then than the morning.’  The German added that his tyre he choose got too small and that lost him performance over the final 2-minutes of the qualifier but summing up he is confident for Q2.


December 3, 2025

Catanzani Top Seed in Chile, as Ripoll impresses with P2

Andrea Catanzani is the Top Seed for the 24th running of the IFMAR 1:8 Onroad World Championship but it is the pace of French driver Maxime Ripoll which is the big surprise in Chile.  The Top Qualifier at the 1:8 GT Worlds back in September, Catanzani’s Serpent would top the times in opening and closing runs of the day, the schedule made up of fourth seeding rounds.  In the second round it was Rapoll’s Xray that raised a few eyebrows as he set the fastest time ahead of 2019 World Champion Shoki Takahata.  Round 3 would see Takahata go fastest and the factory Mugen Seiki driver seeds 3rd for qualifying tomorrow when we will have the first 3 of the 6 rounds of 7-minute qualifiers.  After a bad start to seeding, Toni Gruber would make it four different manufacturers at the top as the Capricorn driver solved his engine/glowplug issues and managed a 4th and a 3rd to end the day 4th.  One of the favourites coming into this World Championship, Japan 2023 Top Qualifier Simon Kurzbuch, didn’t have the day he was looking for finding himself in P5 and with work to do for tomorrow.  Celebrating his birthday today, drivers from the 16 nations racing at these Worlds singing Happy Birthday to him at the end of the opening ceremony, British driver Alex Thurston made it three Mugen MRX7s in the Top 6.

Summing up his day, the first stage in his quest to become a World Champion perfectly executed, Catanzani explained, ‘We work really well on the car, changing little things that make the car different and we choose the right set-up for the last seeding practice.  We need to test something more tomorrow morning to get it perfect but of course the quali will be close with all these guys.  Also because it is 7-minutes you have to be consistent.’  Asked if it is a difficult track to be consistent, the 20-year-old replied, ‘Yes, because I think when your mechanic tells you your lap time you want to push more but if you do you end up hitting something, so you have to be calm and smooth.’  Happy the race, drivers having been on track since Friday, is going to plan asked about the wind, which was particular bad this evening, the Italian said, ‘It was bad but we work all the days for this because all the evening are like this so we work to have a fast car in the morning and a fast car in the afternoon.’  On a positive about the wind, he said, ‘it is always in one direction so when you arrive in that corner with the wind behind you have to stay a little bit safer than in the morning.’

Pleased with P2 modestly describing it as ‘pretty good’, Rapoll said he lacked a little speed in the final seeding round because they changed to his spare engine, but given the conditions of the wind and the hot track he said his RX8 was still good.  On the wind and the challenges for driver he explained, ‘It makes it pretty difficult because it is unpredictable and you can’t do anything on the car for it so it is a bit of luck driving when it catches you.  You just have to deal with it and cross the fingers that you are a bit lucky.’  With his 3-lap pace looking very strong, his best time only 5/100ths of a second off Catanzani, asked how he felt he his long run pace is, the 19-year-old replied, ‘For me it is more easy to drive a longer run.  The car is pretty good and easy to drive so I am looking forward to the qualifying and running for 7-minutes.’

Takahata summed up his P3 with ‘so, so’ explaining that he had a mistake on the third lap of each of his counting runs.  The newly crowned Japanese National Champion said his car, engine, and overall package is good but he will make a change for tomorrow to try and get a little more steering.  Flying the flag for reigning World Champion engine tuner Max Power, the 31-year-old will also ‘turn up the power’ on his engine for qualifying.

With his crew’s thoughts that a bad batch of glow plugs was the reason for his engine issues in the first two seeding rounds proving correct, with a plug from a different batch getting his Ielasi Tuned engine back to speed again, Gruber was relieved to solve that issue but with the wind picking up for the afternoon the German driver said ‘Round 3 the driving was difficult because of the wind.’  While getting himself into the top heat of qualifying, the final round his best ranking of the day, the reigning ENS Champion added, ‘we still need to improve the balance of the car to have a better feeling and to overall to have better corner speed.  We tried something for the last round and luckily it paid off for us and the car was much easier to drive.  So we hope to build on that positive for tomorrow.’

Reflecting on the first day that thing actually counted for anything, Kurzbuch said, ‘The day was not our best day.  The morning round was good, we had 2nd place but we were still not happy with the setting of the engine and from this point on somehow something went wrong and we have to do a complete rebuild of the car and check everything.  Somehow we couldn’t get an speed anymore.  The engines were good in practice and also the car so somehow there has to be a mistake somewhere.’  Asked if he was going to be in for a late & busy night, the 33-year-old replied, ‘No. We will know finish the day, and early tomorrow start off with a fresh brain and put everything together for tomorrow.’  On whether 7-minutes will suit him better or if the problem is bigger than just outright pace, he said, ‘for me I think I am faster over 7-minutes than 3-laps but of course today I was also not fast and the pace was not there yet.  We hope for a better day tomorrow.’


December 2, 2025

Catanzani from Ripoll in early 1:8 Worlds seeding

Having taken the overall TQ at the 1:8 GT World Championship in Chile back in September, it is Serpent’s Andrea Catanzani who leads the way in early seeding at the IFMAR 1:8 Onroad World Championship from Maxime Ripoll, the French Xray driver impressing onlookers with his speed here at the large Club de Aeromodelos de Chile track in Santiago.  With Catanzani the benchmark in free practice, the Italian carried that momentum into the first of the four seeding rounds with a best time of 55.443 over 3-laps with Mugen Seiki’s Simon Kurzbuch his closest rival with a 55.459 as team-mate Shoki Takahata complete the Top 3 ahead of Ripoll.  With changing track conditions the biggest challenge for drivers, as things hotted up after the first seeding on a cool track, it was Ripoll who had everything perfect to go fastest with a 55.499 just ahead of Takahata.  Making a changed that didn’t do what he expected, Catanzani was 3rd fastest ahead of the Mugen Seiki of top British racer Alex Thurston.  One of the pre-race favourites coming into the 44th running of these championships off the back of a championship winning ENS season, it has been a tough morning for Capricorn’s Toni Gruber,  the German experiencing engine issues in both runs.  While the car runs fine in the warm-up out on track it loses power and when they pit they find the plug is bad leading them to believe, having had the same problem twice, that a bad batch of glow plugs is the issue.  The 2023 1:8 GT World Champion will be hoping plugs from another batch will give him a change to seed strongly over the final two practices round for tomorrow’s start of qualifying, each driver’s best two points finishes from the four rounds determining the order for the heats.

Summing up his morning Catanzani said, ‘The first one was good.  The second one we tried something different because we know the track is always changing condition but it didn’t work like we expected so we just finish the practice and got third.’  He continued, ‘We know what we have to do for the next one.’  On his pace since practice started for the event on Friday, he replied, ‘the car is really good, especially in the morning, there is no wind and the track is still cold but then in the afternoon the wind starts so the car is a little bit sliding in the rear and also because the track gets more hot.  We are still finding the good set-up for this.’  The only leading contender to have previously raced here, asked if his GT experience was an advantage, he replied, ‘Only maybe for the first day because when the fastest guys arrive on track they need less than 1-day to learn the track.’  Ask about the technicality of the track for 1:8 Onroad, the 1:8 GT drivers loving the layout and size, Catalan said, ‘It’s not simple because there is also bumps you beed to avoid so it’s technical and fast.  If you stay near the white markings you are fast but if you go too much and hit them you loose time, it is a fine line.’

Racing 1:8 Onroad competitively since 2017, Chile is Ripoll’s 3rd World Championships.  With Fontana in 2019 very much a learning process, 2-years ago in Japan he looked on target to bump up to the Semi Finals until a tyre problem put him out of contention.  With a European Championship podium finish to his credit, the 19-year-old is now making a strong impression in Santiago.  A 2-time French National Champion, he said his car has been working well and unlike his rivals doesn’t seem to be as affected as much by the day’s changing track conditions.  He explained, ‘we came here with a base set up and just made some little adjustments like the shock oils and springs, the flex on the radio plate, and the roll centre, but really small changes.  For me the car is good all the time.  We change nothing compared to this morning.’  The Max Power driver added, ‘We won’t change the car for the next one but we might change engine just to test and to preserve the best one.  I already have two good engines ready to go.’  Asked about the track, Ripoll said, ‘It is super big, super fast, and while I like it I prefer a little track and a more technical track. For me this one is easy, maybe too easy for a World Championship.’

Giving a run down in the first half of seeding, Kurzbuch said, ‘It could be better.  In the morning run we had a bit of understeer in the car but the rest was good.  For Round 2 we changed to another engine just to try everything but the setting was too rich and I could only do my fast laps at the end with the engine still too rich so we could not be competitive that one’.  Overall the 2015 World Champion said their program is going good and they have learned a lot and ‘what we have seen so far is like in almost every heat someone else is the fastest, someone gets everything right for the conditions and set-up.  I think that is the difficult part for qualifying to try to get every run everything perfect.’  On the changing conditions, the Swiss driver explained, ‘First of all the first run is cold and no wind, the second run is no wind and hot, and then we start with a little wind and hot, and then we have hot and a lot of wind, that’s the daily programme.’  On the layout he described it as ‘fun to drive, it’s perfect, it’s a good track.’

Team-mate Takahata felt the balance of his MRX7 was better in the second round due the track conditions having not made any set-up changes.  Happy with how his car has been running since arriving here for practice, the 2019 World Champion is however not a huge fan of the track finding it completely alien in terms of size compared to the much smaller tracks he races on in Japan.  Taking his World title win in the US, he said the CACH track is bigger than the now no longer existing Steel City RC Speedway in Fontana.  On car set-up he said he doesn’t plan to change anything highlight that with the track so different each run it is hard to know if the change worked or it was the track.  Overall the 31-year-old is  happy with his pace describing the new car, with which he just recently won the Japanese National title, as ‘very good’.  Making the switch from long time engine sponsors O.S to reigning World Champions Max Power this season, he said the Italian engines are ‘super strong’ here.


December 1, 2025

A decade on – life is different, but the drive & focus on winning in Chile are the same for Kurzbuch

2025 marks a decade since Simon Kurzbuch became the Champion of the World.  A driver Red RC have had the pleasure of following on his journey up through the ranks and into 1:8 Onroad racing history books, we first got to know him through the early days of the Euro Nitro Series and as one half of the talented Swiss racing duo that was himself and Silvio Hachler.  Unfortunately we would miss him claiming the biggest prize the sport has to offer, Brazil in 2015 the only 1:8 Onroad World Championship we have missed since going online in 2006.  Thankfully Simon, being the super nice guy he is, hasn’t held that against us and just before he caught his long flight to Chile we had a quick chat to get his thoughts on where he feels he is at as he attempts to become only the 3rd driver to ever win IFMAR’s original WC category more than once.  If he can pull off that feat he would also be the first non Italian to ever do so.  While legend of the category Lamberto Collari won’t be in Santiago for a chance at a 10th World title, and defending Champion Dario Balestri’s chances of a hat trick are on hold as he also wont be there, Simon did address the big talking point around this year’s 24th running of the Worlds – the absence of the entire Infinity team.  ‘I am disappointed that the Infinity drivers are not coming, it is a real shame for Kenji that none of them are coming, but no Infinity does not affect anything from my side in how we approach this race.  In the end there are still very good drivers there and you need to beat them and to beat them you need to work properly before the race in your preparations and then work hard when you get to Chile.  I have a really good focus on the race so from this side it does not change anything if Infinity are there or not.’

Now 33-years old, on where he expects his main competition to come from, without hesitation he replied, ‘Toni (Gruber), Shoki (Takahata) and (Andrea) Catanzani, Catanzani is fast and someone to really watch.  Maybe there will be some other surprises, we will see, but I think these are the guys.’  Asked the difference between the Simon of then (Brazil, 2015) and the Simon of now he replied, ‘There is not a big difference I would say.  A lot of things are the same, of course my focus outside of racing is a bit more into work.  Back at that point of my life I was studying and also had a great time with Silvio Hachler, who is a really good friend.  We studied together and could manage to do as much racing as we wanted to and it was an amazing time that time which also boosted us for good results and everything.  That is the main difference.’  He added. ‘On the other hand my father is still there racing with me and supporting me a lot.  Alex (Kempe) was also there in Brazil as support for Shepherd and now he is directly helping my father so we are looking forward to defend the title of South America.’  While the same dream team that helped him secure the TQ honours at the last World Championship in Japan 2-year-old, and this year’s European Championships, bSimon said it’s not quite the ultimate dream team, his brother having partnered his dad in executing the many pit stops en-route to becoming the World No.1 in Brazil.

Asked if 1:8 Onroad and its high revving little 3.5cc engines have notably evolved since the last Worlds, the class having had almost 50 years to perfect the concept, he said, ‘I think the engines made a big step again the last two years.  The cars have developed a bit also.  I see the difference with my new Mugen but also the other manufacturers have worked to get more from their cars so it is for sure a bit faster.’  On engine and in particular his own program with Ielasi Tuned, owner Daniele Ielasi a rival in Brazil but now one Simon’s key sponsors along with Energy Fuel, who supplied the control fuel for both the 1:8 GT and now the 1:8 Onroad Worlds, he said, ‘reliability is now on a really really good level compared to what we had over the past 10-years in our sport.’  He added this is the result of ‘development but also hard work from Daniele.’

Showing that their is no doubts over his outright speed in terms of being one of the fastest drivers on the planet taking the TQ in Japan on Infinity’s home ground only for a wing issue and engine tuning to thwart his effort in the final, Simon said, ‘this year at the Euros I could manage to TQ against all the Infinity guys and everyone so the speed is there yes, for us it is important to have a clean final.  That is the main focus and it’s been the focus for the last weeks and months in preparation to have more consistency there.  Even though in the last ENS it was not the perfect final race practice but things that happen you learn from them and they are over’.  Suffering a flameout in the last fuel stop at the ENS finale, he explained this was the result of a ‘quick & messy pit stop and lets say a lot of fuel came out and the engine flame out was due to that.’

On going to Chile armed with the new Mugen Seriki MRX7, it three years to the month since he made the switch from then German brand Shepherd after a long stint to the Japanese manufacturer, Simon gave the upbeat reply, ‘Actually it was a great season for the new car.  I could use it since ENS Ettlingen so I have a lot of experience. Durability and everything is as Mugen always was.  I think we could make another step forward with the car in the last month before that I couldn’t spend too much time on the track practicing due to other reasons. We will also get so much practice in Chile I think we will improve the car even further.  There is a lot to discover still.’

Having not yet sampled the track (at the time of our chat), asked his thoughts from what he has seen he replied, ‘It looks like Fontana (2018 WC host track).  I think the grip level will be more suitable for me than it was in Fontana because that was super high grip.  The layout in Chile looks good, and fast, so I think it will make for a proper World Championship.’  On that note we can’t wait to follow how it all unfolds at the impressive CACH facility.

Red RC’s coverage from Chile, which is presented by Capricorn, Radbody, T-Works, and IFMAR, will start on Tuesday (Dec 2nd) with four rounds of seeding practice and continue through to Saturday’s title deciding 1-hour Main,.


November 30, 2025

1:8 Onroad World Championship coverage presented by Capricorn, Radbody, T-Works, and IFMAR

Having hit a landmark of telling the story of how 50 World Championships unfolded when we reported on Marcus Kaerup’s 1:10 4WD Buggy World title win in Australia, Red RC is excited to be travelling to Chile to cover the 1:8 Onroad World Championship, our coverage presented by Capricorn, Radbody, T-Works, and IFMAR.  As we kick off the first of our next 50 World Championships, this one is special because it was IFMAR’s original World Championship category that was also the first World Championship to be covered here on Red RC back in 2007 in Argentina.  With a certain Lamberto Collari racking up the 8th of his 9 World titles, now 18-years later the championship is back in South America and having missed the last one Red RC are definitely going this time round for what in our opinion is the Formula 1 of RC Racing.  Unfortunately while Collari and all of his team-mates at reigning World Champion manufacturer Infinity won’t be making the trip to the amazing CACH facility in Santiago, we are still going to be in for the intensity that only a World Championship brings out in drivers and manufacturers.  While Japan 2023 winner Dario Balestri doesn’t appear on the entry list, it is led by three World Champions – Simon Kurzbuch (2016 World Champion, Brazil), Shoki Takahata (2019 World Champion, USA) and Toni Gruber (1:8 GT 2023 World Champion, Australia) – they will face the next generation of potential World Champions in the form of drivers like Andrea Catanzani who unlike the three World Champions has been to the track previously where he was the Top Qualifier at the IFMAR 1:8 GT World Championships back in September.

Our coverage is only possible thanks to the support of our sponsors and a specialist manufacturer born out of Nitro Onroad racing, Capricorn and its owner Patrizio Rossi have been staunch supporters of the category so we are honoured that they came onboard for this the 24th running of the 1:8 Onroad Worlds which was the founding category for World Championship RC racing when it crowned its first Champion in 1977!  A company that has been instrumental in Red RC’s World Championship coverage post Covid, US body producer Radbody, as fans of all things fast and aerodynamic, are the third of our sponsors making the fourth & final stop on the 2025 World Championship World tour possible.  Long time supporters of Red RC, aftermarket parts and accessories producer T-Works need no introduction and we are delighted to team up with them once again after they supported us last year in attending the 1:10 Nitro Touring Car WC at Huge RC in Thailand.  Having dealt with them at each and every one of the previous 50 Worlds we’ve covered, they are the ones responsible for the race that awards the greatest prize in racing after all, we are very grateful to the World governing body IFMAR for their assistance in ensuring the race with the longest history records will get an in-dept 2025 chapter update!  Red RC’s coverage will begin on Tuesday with Seeding Practice and the Opening Ceremony before we quickly get down to the serious business of qualifying with it all culminating with the crowning of a new World Champion on Saturday (December 6th).