3 replies to this topic
  • reed_YZ426

Posted September 10, 2001 - 05:05 PM


ok well, i was just wondering if anyone knows if yamaha will come out with the YZ450F next year for 2003? and if so will it be a 450 or 500? i was argueing with a friend of mine he hasnt been watching the outdoor nationals and he keeps telling me that john dowd isnt riding the KTM 520SX. because 520cc isnt aloud and i told him that he was its not like im stupid. hes a moron but anyway back to my question. do you think yamaha will be coming out with a YZ450F or YZ500FM for 2003? i know at www.yamaha-racing.com in europe they got a YZ500F i hope they come out with that! if not though i hope they atleast bring out a YZ450 for 2003. im going to wait off instead of buying a new pipe and silencer im just going to buy that when it comes out in 2003 cant wait!

  • sirthumpalot

Posted September 11, 2001 - 02:28 AM


I really have no information to back this up, but I'm guessing that if they increase the size at all it will be a 450, at least in the USA. If I remember correctly the AMA limit for 4-strokes in the 250 class is 450cc (someone correct me if I'm wrong). If this is the case then Yamaha producing a 500 in the US wouldn't make much sense unless they are willing to give up their 4-stroke seat in the 250 class (I don't think that they are).

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  • SteveW828

Posted September 11, 2001 - 03:25 AM


I am pretty sure the rule now is 250cc through 550cc four strokes in the 250 class. That is why John Dowd races the KTM520SX. The talk is in the future the rule will be amended to a max. 450cc. That is why Honda went with a 450 and probably Yamaha will do the same.

New rules may also allow a 125cc thumper to compete against the 80cc 2 strokes in the super mini class.

I am not an expert so please anyone chime in if I am incorrect.

  • BBRguy

Posted September 11, 2001 - 05:52 AM


Yes you are correct. but just to clear one little thing up. the big orange bike, isnt a 520cc machine, it is more like a 502cc...then just chose to go with the name "520". i dunno why. but im almost positive that it is a 502cc.either way. IF yamaha bumps displacement up, it will be to 450. and IF the AMA still is the reigning body of motocross and supercross at the end of this year (i read a report that said the AMA and SFX are battling for "custody" so to speak) then im sure they will adopt the 450cc rule for a four stroke in the 250 class.which means that KTM will either have to decrease or increase the cubic centimeters in one of its bikes...just my two cents.

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