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Proposal for 250cc GP 4 Stroke Replacement

By Paul Crowe

MotoGPIn a move that was certainly expected since the 500cc MotoGP bikes were phased out, Dorna Sports CEO Carmelo Ezpeleta proposed a 4 stroke replacement class to begin in 2011, ending the 250cc 2 stroke class after 2010.

We want the class to be competitive, cheaper and a prototype series. We already had some manufacturers announce that they would not be continuing to make two stroke machines, because of the production cost and the fact that they were not interested in making that kind of street bike. They aren“t developing this type of techonology and want to do other things.

He didn’t specify what the new class would be but some are suggesting 4 cylinder machines somewhere in the 600cc area.

Thanks for the tip, Aaron!

Link: MotoGP.com

Posted on May 19, 2008 Filed Under: Motorcycle Racing

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Comments

  1. anon says

    May 19, 2008 at 12:32 pm

    600cc would be a natural from a commercial standpoint for the manufacturers, but MotoGP is supposed to be about prototypes, not street equipment. Looking back at the 125cc, 250cc, 500cc days, why not keep the same pattern for four strokes? Just half the displacement every time they move down a class: 800cc, 400cc, 200cc

  2. Mr. Tanshanomi says

    May 19, 2008 at 12:37 pm

    I’d rather see a 400cc class, or perhaps 400cc four, 500cc twin, 650cc single formula.

  3. aaron says

    May 19, 2008 at 12:40 pm

    I’m a little disappointed with this proposal, particularly the suggestion that all motors be “prototype” inline fours. why would anyone want to build a completely new version of a production engine just for this class? (remember the harris WCM? started with a R1 motor, after tons of work to make it a somewhat competitive motogp unit it was not allowed to race… due to the R1 roots, it did not meet the “prototype” requirements)

    the old 250’s were just under half the power, and something like 70% of the weight of a 500 gp bike, limited to 2 cyl max. that means the new class would be 115 hp (lower than 600cc production bikes!) and under 230lbs… (yeah right!) to be the same “stepping stone” up to motogp… instead we’ll likely get 85% of the power and 90% of the weight…yipee!

    I say maximum 3 cyl, 450cc, with a 10-15lbs weight penalty to triples vs twins. follow this with a 250cc single cyl class to replace 125s.

  4. taxman says

    May 19, 2008 at 2:43 pm

    wasn’t someone working on a 450cc single class using converted dirt bikes?

  5. todd says

    May 19, 2008 at 3:14 pm

    600 fours, yawn. I doubt anyone would be interested in this. It wouldn’t be any different than the 800cc stuff. I like Mr. Tanshnomi’s and Aaron’s ideas much better.

    -todd

  6. Clive says

    May 19, 2008 at 4:23 pm

    Actually, it’s already been announced. They’re goign to be four-stroke inline-fours of between 625 and 650cc and they’ll be a tenth of the cost of 250cc two-stroke bikes. See here for details: http://hellforleathermagazine.com/2008/05/250gp-replaced-with-fourstroke.html

  7. aaron says

    May 19, 2008 at 6:22 pm

    I’d love to buy a privateer bike for 3 grand! hook me up…..

    really – when a tz250 or honda rs250 goes for around or under $30,000 – do they expect that a privateer could get into the sport for a tenth that? they quote a lease price on a full factory bike that could win the championship as the base price that is used for the calculations…lets see – more chassis revisions per year, continual engine upgrades due to the novelty of these engines, same high grade components, etc… show me the savings!

    remember how the one set of tires per race and multi race motors were going to drive costs of formula one down? (for that matter, remember how 800cc motors were going to slow down motogp?)

  8. christopher says

    May 19, 2008 at 9:11 pm

    too bad. seems like it’d be more fruitful for everyone if they kept the 250cc formula and just translated it to four strokes. imagine the mechanical indecency and out of this world innovation we’d see if they had to make crazy power with such a tiny engine. not to mention the lengths they’d be stretching to create the perfect chassis. 600(ish)cc four cylinders? don’t we already have enough supersport series? come to think of it, this sounds a wee bit like something we Americans call “Formula Extreme” . . .

  9. Matt in NC says

    May 19, 2008 at 9:33 pm

    The 450 single setup is a proposed 125cc replacement for entry level racing.
    http://www.450moto.com/

    Still way cool, and I’d love to have one as a track bike.

  10. motoxyogi says

    May 20, 2008 at 4:27 am

    How on earth are they going to make 4-strokes cheaper than 2-strokes. they’d have to put serious caps on the amount of tuning allowed to keep the prices down which would how much anyway? And that would be even more difficult if they are supposed to be prototypes.
    Personally i think 2-strokers still have quite a bit of future ahead of them what with direct injection and other things bringing about cleaner more efficient engines.
    Another suggestion is what if they reintroduced forced induction on gp racers. Anyone remember the BMW Kompressor?

  11. mark says

    May 20, 2008 at 11:25 am

    If the purpose is to have a meaningless and forgotten class that is a feeder to the Big Time, then this is a way to start going about it, though I don’t see the manufacturers buying in.

    After all, why would they? The have already MotoGP (800 prototype), WSK (1000 and 600 inline fours), various country prod championships (all 1000 and 600 inline fours), plus the twins, endurance, and so on.

    If they are serious about smaller bore racing, then perhaps they should open this class up to more makers and have a true prototype class that allows an anything-goes approach, limited by fuel economy of say 80mpg, based on an allocation for each race (race length 160 miles, you get two gallons of 95, sir. Good luck!). Blowers, suckers, two-strokes, electric hybrid: bring them all on, so long as then have two wheels.

    My $0.02

  12. aaron says

    May 22, 2008 at 1:15 pm

    I say give up limiting the classes by cc’s – go by tire size. scrap all traction control systems, divide the classes like this:

    motogp=all the power you can feed through a 190 tire, with the weight required to keep it in line.

    gp middleweights: all the power that can be fed through a 150 rear

    gp lights: 120 rear tire

    all classes: four stroke only, common fuel supply, single tire manufacturer, no limit to # of cyl. (although Wankels are limited to middleweight and lights, at first)

  13. Dr. J says

    May 22, 2008 at 11:12 pm

    I think a problem with tire size limitations is that amount of grip a tire has is based more on the tire compound than the overall surface area (although footprint shape is important).

    So larger tires don’t neccesarily accomodate more horse power, although they might last longer before going off.

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