125s To Be Replaced By Four Strokes From 2012

It took only a few hours after the announcement of the introduction of the Moto2 class for speculation to begin about the future of the 125s. With the demise of the 250s, the MotoGP paddock had at a stroke become an overwhelmingly four-stroke paddock, and it seemed only logical that the 125s would quickly follow. Whenever either Dorna boss Carmelo Ezpeleta or FIM president Vito Ippolito was asked about this, however, they denied there were any plans to change. Their arguments were that the 125s were cheap to run, they had plenty of national series to support fresh young talent, and bikes and parts were in plentiful supply. There was no need to change, in their view.

And yet change is coming. According to MCN's Matthew Birt, the 125s are to be replaced by a new four stroke class beginning in 2012, at the same time as the new rules in MotoGP come into effect. The class will be composed of 250cc four-stroke single cylinder machines, MCN reports, replacing the 125cc two-strokes currently being used. The decision has been made in response to the thinning out of the 125cc grid this year, which has come about in part due to the arrival of the new Moto2 class, which has attracted large amounts of sponsorship, talent and public interest from the 125cc class.

Rumors of a switch had first emerged at Jerez, with one team telling MotoMatters.com that they had been informed by Ezpeleta himself that a new class would be replacing the 125s from 2012. All efforts at trying to corroborate this story failed, with members of several long-serving 125 teams denying they knew anything about it, saying that their plans revolved entirely around the continuation of the 125cc class in its current form. Various paddock insiders were sceptical about the story, believing that there would not be enough time to develop bikes and engines in time for the 2012 season. Despite having his doubts about the question, veteran journalist Dennis Noyes did point out that the last time that Carmelo Ezpeleta spoke on the issue, the Dorna CEO said the 125s were safe through 2011, a date seemingly chosen with great care.

The one difference between the Jerez rumor and MCN's report is the size of the engines, with rumors at Jerez speaking of 300cc four-stroke singles to be introduced, rather than a 250. The smaller capacity would make mroe sense, however, as there is already an abundance of 250cc four-stroke motocross bikes currently being raced, and already being tested in roadrace chassis, such as Moriwaki's MD250H. But the cost of uprating 250 MX bikes to ensuring they hold together under roadracing conditions is probably large. The Roadracingworld website ran an interesting story last year about one team manager's experience of running 450cc MX singles in roadracing and dirt track chassis, and that team had run into a lot of mechanical problems with the engines, the singles requiring more work than expected to keep them running.

The change is almost certainly triggered by the drastic thinning out of the 125cc field. Although the grid is still relatively well-stocked, the quality of the entries has dropped off significantly. Once past the top 5 or 6 riders, the gap back to the rest is worryingly large, 10th position often being over 2 seconds behind the polesitter during qualifying. When we spoke to Tech 3 team boss Herve Poncharal about the possible demise of the 125cc class, Poncharal was not surprised at all. "If you look at the top 15 in each class, by far the biggest gap is in the 125s," the Tech 3 boss pointed out.

Despite professing not to know about a change to the 125 class, Poncharal admitted that the temptation to add a Moto3 (as the class is probably going to be called) team to the Tech 3 family was very great. "My first reaction is I would be very interested, very excited, I would love it," the Frenchman confided. "But then five seconds later, when I think what I've been going through with the Moto2 team in the winter, I'm not so sure!"

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given the success of moto2 this looks like a good move, but is it going to be much cheaper to run in moto3 than in moto2?

won't it still be around €100,000 per bike with the stock engine being provided by dorna? if you're gonna stump up that much cash wouldn't you rather be in moto2 anyway?

obviously there'll be a lot more cash available since people won't be buying exorbitant RSA machines but still...

Total votes: 158

I'm not really sure that the math works out on this one. How much cheaper will these bikes really be? I'm not sure there are many places to save money over a Moto2 bike.

Using a single seems logical at first givent he number of series starting up using MX motors in roadracing frames but none of those formats have really taken off yet.

It seems to me that a twin would make a lot more sense. 250cc street twins are fairly mature and can take the mileage. MX singles need to be rebuilt way too often to prove economically viable and that doesn't even get to the question of failures on the track.

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Total votes: 147

When they don't have enough riders in a class, is changing the rules suddenly the magic guarantee to get a fuller grid just because it worked for Moto2? It's not set in stone that the Moto2 field will be that big again next year. This year it's a free for all, because nobody had experience and basically everyone a chance to win the title. But that won't be the case anymore next year and seeing quite a lot of Moto2 teams with just about zero sponsors on their livery, I can't imagine all of them continuing next season. And who says it'll work the same for 125cc anyway.

125cc is a great size for a feeder class, most riders are very young (and small) and come directly from their country championships where they rode the same bikes. As far as I know the Spanish championship is the only one at the moment with a Moto2 class, i.e. building up potential world championship riders on the same bikes. How long would it take all the country championships to kill off and change their current 125cc classes (which you find pretty much everywhere), so they could bring up young talents on the same bikes before they move to the world championship?

Total votes: 155

Herve Poncharal goes on about cost a lot, but he must be making some kind of money if he's excited about the chance to run a 3rd team.

Total votes: 157

I can see this working. In the Dutch national championship for example , 250cc four-strokes are already allowed to race in the 125cc class. Although their bikes are not yet competitive , there are a couple of interesting competitors (for example http://www.slootenracing.nl/content.php?p=info&sp=de-motor)..

Racing a competitive 125cc bike is very, very expensive and the lanky Dutch riders don't fit on a 125 bike... Which is why Ten Kate is trying to start an affordable Moriwaki MD250H Cup over here in Holland (with an annual budget for bike and maintenance of +/- 5500 EUR).

A class like that on a National level would make a great feeder into the bigger championships. Furthermore , there is no logical path to follow after a 125cc 2-stroke anymore. 250cc is gone , so you'll end up racing a 600cc bike which seems a very big step.

Total votes: 157

The first insult to GP heritage was making class built around a spec street engine. Now replacing a 125, likely the most focused and optimized racing machine ever, with a dirt bike engined based bike. Great. A 250 street twin engine likely weighs almost as much as an entire 125 GP bike.

The bottom line is that GP racing in the hands of its current caretakers has completely lost direction and is struggling to remain relevant. Instead of taking the lead by having energy based class limits and actually fostering technology innovation (besides GPS-based engine mapping- useless on the street) they remain firmly on the path to converting GP racing into an entertainment spectacle to compete with reality TV.

Last year KTM tried to innovate in the 125 class with a small front wheel based KERS system.
FIM/DORNA response: ban it.

Inaugural TTXGP is a 'success'.
FIM/DORNA response: splinter the effort by having competing series.

We have not heard any 125 teams complaining about high costs.
FIM/DORNA 'response': let's use an unsuitable engine design that will require a lot of hot-rod parts and frequent rebuilds that will increase costs.

Asking Herve Poncharal about these rule changes is like asking an addict if they want more dope- yea, sure, bring it on!


Total votes: 149

Dorna has actually brokered a couple of cost-cutting deals for the 125s, but not much mention has been made publicly. The series was in cost troubles again, I believe, leading into this season. I definitely agree with this though,

"The bottom line is that GP racing in the hands of its current caretakers has completely lost direction and is struggling to remain relevant."

Too true.

Total votes: 164

Fuzz10, the 250 singles are the same size as the current 125cc bikes, so sorry they wont be any bigger. onlt in capasity

In Australia Honda ran a almost factory effort with the MD250. it was so slow they made it a 300cc just to try to keep up with clapped out 2000 model Apirilias and old men on RS125 Hondas. One of the fastest bike here is a $20,000 TZ125.

And the 125cc bikes here are 5 seconds of world pace any way. so the four stroke will be evn slower like a kids club day.

Total votes: 154

Flattracker ; The size of the bike and running costs are the main reasons Ten Kate wants to introduce the class in Holland (http://www.tenkateracingproducts.com/talentgezocht/).

And sure the bikes will be slower than the current 125's (at first). I don't know about Australia , but the current situation is diminishing the Dutch championship's 125 grid and can't be maintained.. Something needs to change.

According to Bakker , his bike will be 80 percent cheaper to run than the 125's. His specifications are 45 BHP / 80 Kilograms.

See :

Total votes: 141

125 2S twins were too expensive (remember Morbidelli?) so they switched to 125 2s singles. Honda built an engine out of their 125 MX engine with reed valves and we all went racing. It was quite a bit later before Aprilia upped the ante so much that you had to have an A-Kit engine from them to win. Even now the vast majority of national club 125s use the same Honda engine that is not so much different from an MX engine.

Replacing Aprilia's beautiful but horribly expensive disc valve singles with MX based 250 singles seems OK to me. Just until they stop being MX based and turn into another expensive money pit where you have to have a KTM-Aprilia to win. The good side is that there are at least 6 potential engine manufacturers. And a lot of people who know how to get power out of a 250cc cylinder.

Total votes: 137

Sad news.

I wouldn't dismiss Poncheral's honesty. Nor would I lay the blame for all the worlds racing woes on the feet of the FIM and Dorna. The FIM isn't some all powerful organization. They are only as powerful as their perceived opinion. They just hold the rights to saying what a grand prix is, not what racing means to anyone or if someone else wants to keep racing without their blessing. Things have changed over the years and so must the organizations. Going against change is no better than saying to freeze development for all eternity (no matter how attractive the idea of 500cc two-strokes is!). Dorna is only as powerful as their business model. If interest in the series really is dwindling, it's their duty to not let it die but rather find a suitable replacement. "Suitable" being the tricky term. I believe the simplicity of the 125 bikes (and in the big picture they are not that simple) is what made them great learning tools. If the increased complexity of a 4 stroke engine is added on, things like water cooling and exotic materials should be eliminated. What about power limits? Number of engines and displacement are regulated in MotoGP. The engine itself is standardized in moto2. Why not try a different approach in this new "moto3" with something like a power limit. Then factories could compete on a level that gave advantages to usable power, efficiency and reliability. If they can do it with an electric motor, great. An air cooled 2 stroke? great. An air cooled 4 stroke twin? great. But if it puts out more than 40 ponies it's tossed out of the paddock. Enter 2 motors every 3 or 4 races to be sealed and live with the consequences. That or race scooters instead. I'd be in favor of that, but I'm guess that's not too popular 'round these parts.

Total votes: 143

if there was a power limit set would people really spend a load of money developing something that is never gonna be more powerful than their rivals? nobody complained before about lack of competition between manufacturers in the smaller categories.

both 125s and 250s were realistically a 1 factory series anyway, Aoyama did something very special last year on the Honda but probably with extra help to secure the final championship and no one with anything but a top Aprilia/Gilera could compete in 250s, likewise no one without an Aprilia/Derbi can compete in 125s currently.

the problem with having 2 specs series in the same event is they're both really doing the same thing. there isn't actually much need to have moto3 as well as moto2 because they're both aiming for the same kind of ideals, cheap, affordable and competitive racing.

if the level of interest in moto2 keeps up i'd be inclined to state you have to run teams in both moto2 and moto3 allowing for 1 rider teams in each for teams with a smaller budget. there needs to be a small feeder class for the whole event to work with riders coming through the smaller categories but will people really wanna compete in moto3 just to give some kids experience, in effect doing all the work to get them ready for moto2 and above?

being a 125cc champion actually means something, likewise with 250s but that is all going to be lost now, you used to be 125cc World Champion, now you'll just be moto3 champion.

Total votes: 149

Only several ways to control power: 1. Air restriction 2. Bore limits, cylinder count, capacity limits 3. Stroke limits, capacity limits 4. Rev limits 5. Fuel flow limits 6. capacity limits

I think everyone knows that I like rev limits best b/c they don't restrict engine design or engine technology (piston velocity) and they don't create steeply diminishing marginal returns if the rules are written properly.

So if you rev limit Moto2 and and Moto3 with a spec ECU to control electronics costs, you don't really need a spec engine. Dorna could contract with Geo Tech and Honda to make sure everyone has the opportunity to buy a spec engine for either class at a set cost, but after the engine is secured, go attract new manufacturers! Companies like Proton, Triumph, MV Agusta, KTM, Rotax, Benelli, Husqvarna, and the burgeoning developing-world manufacturers may not be able to participate in the premier class, but they can probably play in the rev-limited support series. Their participation will improve the entire GP paddock. It's also a good place for people like Motocycsz, Inmotec, Ilmor, and others to cut their teeth and learn what they need to learn before they throw lots of good money into a GP long shot. If nothing else, the lower classes would be a great B2B opportunity for lots of motorcycle people to get together and discuss new projects.

Best part about GP is you don't have to be a multi-national company with mass production facilities. So why are all of the companies giant multi-nationals who mass produce road bikes?!!

Something needs to be done. Slowing development by regulating horsepower is by far the best option on the table it's just difficult to get agreement from everyone about how it's done.

Total votes: 152

I think that's the interesting part. It wouldn't matter how they'd restrict the power. that would be up to the team. The limit would just be enforced rather than directed. If you wanted to put 20mm throttle bodies on an 1000cc 4 stroke to get you down to the limit you could race it. The bore limit on the new MotoGP class is similar in that they set a seemingly minor requirement and it's up to you to figure out how to work out the details. I like the idea of air-cooled alternative as well. When I think of small displacement production bikes sold around the world, I think simple air cooled, fuel injected 4 strokes are the standard. If you could get all 4 Japanese factories and Piaggio on board with the idea that the class can be used for development it could be a success. How about a Bajaj race effort? Expansion into Asia is a goal of the MSMA/FIM/Dorna so I think a class where a few billion more people can envision themselves on familiar bikes would go a long way. There's no reason that the new class has to be as fast as the old class.

Total votes: 142

Horsepower limits with no formula doesn't really put the governing body in control. They could hand the teams a dynograph and say "reproduce these numbers", but then the FIM would have to homologate every engine and every electronic device in order to stop rampant cheating.

Plus, some of the power restrictions are only "soft" controls like bore limits and stroke limits. They assume a maximum piston velocity, but max piston velocity can be improved by spending truckloads of money on lubricants and cylinder liners. Air restrictors don't work consistently over variable air intake velocities. It would be nearly impossible to balance the various formulas accurately without whining and the ultimate adoption of a single power controlling methodology (e.g. 1000cc, 4 cylinders, 81mm bore).

Air cooling is inefficient b/c you've got to keep the compression low and you have to run rich mixtures to control temperatures. It also reduces engine life. It's nice for production bikes b/c it's cheap and reliable enough.

The concepts are nice, but I can't imagine a way to make them feasible.

Total votes: 145

Take off the rear wheel, chain up a dynomometer, you exceed and you either (depending on the timing) don't race, get disqualified and or penalized. You could do it on the spot in Parc Ferme.

Air cooling may be relatively inefficient, but that's assuming there is some need to make just as much power out of the same amount of fuel used now in 125s. Moto2 engines are not tuned to Supersport spec. Why are engines that are in a lower state of tune in an air cooled environment different?

To think of real change you have to think outside of the status quo. Being at the slow end of the GP race day spectacle, they don't have to worry about a lower class out performing them. All they have to do have a competitive race, with relevant and interesting machines while providing a series that holds interest as a development bed for young riders. Why are 120 mph top speeds and lap times 30+ seconds a lap slower than MotoGP out of the question? All I see are later braking points and higher corners speeds coming from something like that. How dreadful!

Total votes: 150

And the best way to get as much as you can it is through the simplest approach: energy limits. They already have energy limits but just use a volumetric unit of measure instead of a unit of energy, then hedge it with details like cylinder count that should be immaterial to GP bike design. I'm far from the first person to say this but changing the rules to allow MotoGP bikes to start the race with 700 megajoules of energy (21L of race gas, 200kW-Hr), Moto2 teams to have 550MJ and Moto3 to have 450MJ would be an easy start. It would let the current teams initially continue as they are without forcing a new investment yet allow technology growth by letting mfgrs/teams and potential ones actually plan for the future not worrying about year to year details like bore size or the homogobility (?) of certain parts. Compressed H2, electric, gasoline, bio-diesel,2S, 4S- use whatever storage medium/conversion device you want, if you can make it competitive, come race. Maybe even cap emissions to existing gasoline engine levels to force 2 stroke innovators to make clean power and not give them an easy way to come in and compete with a dirty solution.

By giving new technologies a level playing field to compete, compare, and develop, the FIM would be fostering innovation in the efficient use of energy, a topic that greatly concerns the entire world, and continue GP racing's relevance in the current world.

As an aside, all of the class limit rules have 'mega' in them which the marketing guys will go wild with and there will be no needless sub-distinctions of 800cc, 100cc, claim team, factory team, etc.


Total votes: 161

I think the hang up with the liter as some end all, manhood-proving size is tiring. I get that it's easier to measure displacement, but stored energy seems even more simple. I like simple.

Total votes: 145

One gallon of racing fuel @ 93 AKI. One gallon of racing fuel @ 150 AKI.

The energy stored in each gallon of fuel (not necessary gasoline) is the same, but these fuel are equal? Energy measurements work with electricity (i.e. KERS), they don't work with internal combustion air pumps.

Control is not an illusion. If you control the fuel, the capacity, and the number of times the capacity is exploded per minute, you can control horsepower. It's just science. Disruptive technologies exist, but power can still be controlled without undue strain on the competitors.

I believe I know why they can't use rev limits even though Ducati endorsed them way back in 2008, but regardless, they need to control fuel relatively strictly unless they move to electricity.

Total votes: 153

>>Energy measurements work with electricity (i.e. KERS), they
>>don't work with internal combustion air pumps.

Why? Energy measurements work with any type of engine, be it an electric motor, an external combustion steam engine, or an internal combustion engine of any design. Internal combustion air pumps must adhere to the same well defined physical laws that an electric motor does.

>>Control is not an illusion. If you control the fuel, the capacity,
>>and the number of times the capacity is exploded per minute,
>>you can control horsepower.

So intake and exhaust system design, firing order, ECU mappings, airbox design, etc., have no effect on power? Your statement is true in a general sense but in practice that is what drives costs so high, the desire to violate the spirit of the rules while abiding to their letter.

Rulebooks are like any other system, KISS. Every rule has a potential for being bent and/or broken and untold amounts of money are spent pushing these rules to the limit while appearing not to. It's the appearing not to that is the expensive part. It's every chief mechanic's job to study the rulebook for any possible way to interpret rules to your advantage. Smokey Yunick was likely the most renowned rule bender ever in motorsports. He approached it with a religious fervor and in the process spent huge amounts of the factories' cash.

If your one rule is an energy limit then all you need to do is make sure the competitors line up on the grid with the energy storage medium they specified and passed tech approval with. The fewer rules there are, the fewer that need to be policed and the fewer that can be broken.

>>they need to control fuel relatively strictly unless they move
>>to electricity.

They do. Fuel specification is currently tightly controlled and verified. There are 4 pages of specifications and testing procedures for the fuel used at a GP event.


Total votes: 147

If you have two gallons of gas--1 gallon with octane 85 and 1 gallon with octane 100--you can make significantly more power from the high octane gasoline b/c you can compress it harder. Even though you have regulated the energy, you haven't controlled power and you haven't created a situation whereby people have options. Everyone will simply use the most compressible fuel source which will lead to an exponential increase in costs, and it will likely not have any affect on allowing green fuels unless green fuels are serendipitously more compressible than dirty designer fuels. They used designer fuels back in the turbocharged F1 days to raise compressibility and solve other forced induction issues. The fuels were toxic--not alternative or green.

Designer fuels with AKI ratings above 150 are pretty straight forward so I'd imagine that a motivated group of lab technicians could probably achieve AKI ratings in excess of 200 or maybe 300AKI. Ethanol is around 120AKI and it allows for 16:1 compression ratios which is higher than the 14.5:1 that is achievable (I've read) with 100 octane race fuel. If 200 octane allows compression of 20:1, 800cc MotoGP bikes would make around 350hp at 18,500rpm and they probably wouldn't make it longer than 1 session let alone 3 races. Engine reliability would help curb power, but even then you are developing engines that would teach you nothing about running high octane pump gas. It would be chaos.

I definitely agree with KISS 100%. 1000cc rev limited to 14,000rpm or 15,000rpm. Spec fuel. No exotic matrix metals. The end. Do the same with the other classes. Engine problems all solved other than a bit of whining from the MSMA about how "easy" it is. Engine configuration is free. The cost of competing is slashed. New manufacturers will join.

If they had taken this tack in Moto2, your Moto2 project would be legal. I agree KISS is best, but energy limits are not KISS unless you already have a spec fuel.

Total votes: 128

Why does the world championship need to be diluted with three classes? What's wrong with just MotoGP and Moto2?

Total votes: 132

What about the Red Bull Rookies Cup(s)?

What will those bikes be, since the target would seem to be sweeping that direction?

Total votes: 147

I'd like to see it go the other direction with more classes. Underbones anyone?!

Total votes: 138

While I was a little surprised to read about this announcement this morning, it's not entirely surprising. The writing has been on the wall for years. I've read about talk of a Moto3-type replacement class for the 125's ever since I saw a Kawasaki 250cc single-cylinder racer produced for the GP-Mono class in Japan a few years back in a magazine somewhere. The class in Japan is sort of an enthusiast's class with little if any (at least at the time) factory involvement, and there are many makes of engines used in the series.

This class could be pretty interesting. The important thing is to keep such a class fairly affordable, keep it from becoming too much of a small capacity-arms race, and to encourage multiple manufacturers to participate. It's pretty safe to say that the engines, whether of MX origin or otherwise, will need to be developed for road-race use. But of the manufacturers that currently produce 250cc singles, you've got all four of the Japanese Big-4, KTM, Husqvarna/BMW, TM, and certainly some others I've left out. That's a fairly good amount of manufacturer variety. I'm willing to guess Aprilia has/will have a 250cc single in the cards. Can't see them being left out of this class.

Total votes: 148

The big problem is the high maintenance costs a high-revving 250 single will incur. The mainstream media (magazines) in North America don't acknowledge it (except for Cycle Canada which mentioned it recently) but it's commonly known that the 4-stroke MX bikes are way more labour and maintenance intensive than the 2-strokes they replaced. Putting those engines into road race bikes with the sustained high revs will make them even shorter lived.

The best approach if they have to have 4-strokes would be to get away from trying to adopt dirt bike motors and create custom road racing engines like the 1993 Ducati 500/550 Supermono with its extra balance/connecting rod set-up which kept the engine from shaking itself to pieces.

Or go with a 300cc twin which would be half a Moto2 engine and likely run smoother and be able to share the valve port technology used in the larger engines so be less expensive to develop (in theory!).

But whatever the solution, it needs to still function first and foremost as a learning academy and feeder class for Moto 2 and MotoGP. Teams and manufacturers will always spend whatever is required to win, so there's no point trying make any changes on the premise of reigning in costs! If that's the goal, they might as well leave the class spec as 2-stroke singles and give Aprilia the contract to supply the engines.

Total votes: 156

Now that Moto2 seems to be gaining it's footing, one of the key problems that this proposal doesn't seem to address is the jump between a 125 2 stroke or a 250 four stroke single (maybe 40hp) up to a 600cc 125hp moto2 bike. I like the GP-Mono (japanese series) 250 4-stroke concept but still feel that it's a bit club racer-esque for the big show. 125's made a lot of sense when it was doubling displacement each move up (125cc single, 250 twin and 500cc four), largely because the technology was shared, some bikes would even share cylinders and pistons. I like the idea of finding a formula that brings riders up in a natural progression, but be able to be affordable and available enough to foster club and national series around that. In this manner alone, the 250 4 stroke single does make a lot of sense. You can go order a complete Moriwaki 250 or a Harc-Pro chassis today and get started. If you have a custom, spec-engine, like a 300cc twin then unless they happened to be based on an available road bike, people aren't going to be building bikes in any numbers outside motogp.

Total votes: 157

Having run a 250 single 4 stroke off road for a number of years they are helish to keep running if they are performing constantly at high revs. A moto3 class would make much more economical low maintenance sense, running road based 250 twins. All the japanese and italian factories have such a motor why not use it in the same way as Moto2 with any development allowed with regards to chassis design but limit development of the motors!!

Total votes: 125

When I first heard the Moto 3 news the first thing I thought of was the Kawi 250 Ninja engine.

Total votes: 142