Post by: twosmoke595 on December 27, 2012, 06:27:49 PM
"ASK THE MXPERTS: IS MY 2012 KTM 250SX TOO LIGHT FOR THE AMA NATIONALS
Dear MXA,
I own a 2012 KTM 250SX and it only weighs 218 pounds. Is it legal in the AMA 450 Nationals?
As far as the weight goes your 2012 KTM 250SX two-stroke is legal because 250cc two-strokes are allowed to be as light as 212 pounds and still be legal in the 450 class. It should be noted that a 450 four-stroke can't be lighter than 220 pounds. So the weight of your 2012 KTM 250SX is not an issue. But, your 2012 KTM 250SX still cannot be raced in an AMA Supercross or motocross Nationals because the only homologated KTM two-stroke on the AMA's 2013 approved bike list is the 2013 KTM 250SX. Thus, your 2012 model is not approved. Even weirder, the only Yamaha YZ250 two-strokes on the approved list are units made between 2008 and 2010 (which means that the identical 2011-2013 YZ250s can not be raced). Only a manufacturer can put a bike on the approved list...which requires submitting a few parts for tech and a check to the AMA for $3000. Most manufacturers skip paying the fee for bikes that have little or no chance of ever showing up. Additionally, no bike more than five years old can be raced?which means that the oldest approved model for 2013 is 2008.
For clarification, the minimum motorcycle weights for the 250 Supercross/motocross classes are: 194 pounds (125 two-stroke) or 212 pounds (250 four-stroke). And, for the 450 Supercross/motocross classes, the weigh limits are 212 pounds (250 two-stroke) or 220 pounds (450 four-stroke)."
Post by: Stusmoke on December 27, 2012, 11:54:30 PM
From MXA (http://www.motocrossactionmag.com/Main/News/MOTOCROSS-ACTIONS-FRIDAY-NEWS-ROUNDUP-ONE-WEEK-BEF-9628.aspx)
For clarification, the minimum motorcycle weights for the 250 Supercross/motocross classes are: 194 pounds (125 two-stroke) or 212 pounds (250 four-stroke). And, for the 450 Supercross/motocross classes, the weigh limits are 212 pounds (250 two-stroke) or 220 pounds (450 four-stroke)."
That is such BS. How is it fair that the 450 porkers are allowed to loose 20 pounds and the 250 smokers are only allowed to lose like 5? Thats not biased at all....
Post by: motoxr377 on December 28, 2012, 01:40:12 AM
From MXA (http://www.motocrossactionmag.com/Main/News/MOTOCROSS-ACTIONS-FRIDAY-NEWS-ROUNDUP-ONE-WEEK-BEF-9628.aspx)
For clarification, the minimum motorcycle weights for the 250 Supercross/motocross classes are: 194 pounds (125 two-stroke) or 212 pounds (250 four-stroke). And, for the 450 Supercross/motocross classes, the weigh limits are 212 pounds (250 two-stroke) or 220 pounds (450 four-stroke)."
That is such BS. How is it fair that the 450 porkers are allowed to loose 20 pounds and the 250 smokers are only allowed to lose like 5? Thats not biased at all....
I'm with you. That's a ridiculous rule. Thanks for posting.
Post by: Stusmoke on December 28, 2012, 03:48:06 AM
Post by: chump6784 on December 28, 2012, 07:57:54 PM
Now if 125s and 250s were allowed to loose twenty pounds... *whistles*. KTM would be the king of supercross with Ken Rozcen and Dungey on the 125 and 250 respectively.If I were a pro riding sx I would not want to ride a ktm that was 20 pounds lighter than stock. The bike would fold.
Post by: Stusmoke on December 28, 2012, 11:16:39 PM
Now if 125s and 250s were allowed to loose twenty pounds... *whistles*. KTM would be the king of supercross with Ken Rozcen and Dungey on the 125 and 250 respectively.If I were a pro riding sx I would not want to ride a ktm that was 20 pounds lighter than stock. The bike would fold.
How do you mean?
Post by: 2T Institute on December 29, 2012, 12:02:46 AM
Now if 125s and 250s were allowed to loose twenty pounds... *whistles*. KTM would be the king of supercross with Ken Rozcen and Dungey on the 125 and 250 respectively.If I were a pro riding sx I would not want to ride a ktm that was 20 pounds lighter than stock. The bike would fold.
How do you mean?
Tell me where you would shave almost 10kgs off a 125? Even using magnesuim......everything and titanium springs you would get maybe 2-3kgs tops. Even that would be stupidly expensive.
Post by: Stusmoke on December 29, 2012, 02:37:38 AM
Now if 125s and 250s were allowed to loose twenty pounds... *whistles*. KTM would be the king of supercross with Ken Rozcen and Dungey on the 125 and 250 respectively.If I were a pro riding sx I would not want to ride a ktm that was 20 pounds lighter than stock. The bike would fold.
How do you mean?
Tell me where you would shave almost 10kgs off a 125? Even using magnesuim......everything and titanium springs you would get maybe 2-3kgs tops. Even that would be stupidly expensive.
Carbon fibre. People have made a 160 pound CR125. Someone made a thread about it here somewhere.
Post by: msmola2002 on December 29, 2012, 03:57:49 AM
Carbon fibre. People have made a 160 pound CR125. Someone made a thread about it here somewhere.
You would still need to use the oem frame. And as much as CF is strong it is also brittle. Not really suitable for an MX bike in a structural capacity. Don;t we have an army of guys here who bitch about how an aluminium frame is the devil as it does not flex? CF would be worse!
Post by: Stusmoke on December 29, 2012, 05:14:58 AM
Post by: chump6784 on December 29, 2012, 06:31:43 AM
Fmf knocked off nearly 20 lbs from a 250sx but they did pretty much everything possible to do it.
Post by: Stusmoke on December 29, 2012, 07:34:54 AM
Post by: cnrcpla on December 29, 2012, 03:06:13 PM
Post by: msambuco on December 29, 2012, 03:49:59 PM
Also the pro's put a huge amount of stress on a frame and add gusseting to their frames for added strength which adds weight to the standard frame. That is what I ment by saying the bikes would fold. I am sure I have heard that even the factory 4 strokes don't get that close to their weight limit, especially the 450's.
Fmf knocked off nearly 20 lbs from a 250sx but they did pretty much everything possible to do it.
I would sometimes go to races with a guy from NY who raced pro. Finished 8th in the 500 nationals one season. Anyway we went from NY to Budds Creek one February to get our season started early. He pulls off that track saying his handling sucked and could I get started checking what was loose. We couldn't find anthing wrong but noticed paint missing from the steering stem. He bent the stem back without crashing, just riding fast.
Post by: beaner on December 29, 2012, 09:40:43 PM
Post by: Stusmoke on December 30, 2012, 12:46:35 AM
I remember the post Stu, but if I do recall correctly he used a cr85 frame and put the 125 engine in it with the carbon fiber.
Maybe you're right I honestly don't remember properly.
Thanks beaner.
Post by: bearorso on January 01, 2013, 10:12:18 AM
Loosing weight = $$$$$$$$$$$$$$
That's part of the reason for weight limits.
Modern bikes - means the weight limits should drop down a bit. Not a huge amount, as only the Big Teams / Very well off will be able to meet those weight limits, safely.
250 4t and 2ts, can, fairly, relatively easily, meet 212lb , with empty fuel tanks. Though for a couple, it would still mean a big investment. 450s reaching 220lbs, with empty tanks, based on std bikes - a pretty bloody expensive ask.
Easier to achieve weight reductions, if it's done in the design stage. Whether or not a 4t, especially, remains affordable (well, you know.....) to the average Joe /Joette, when they are made by the factories as lighter, is another thing............
Post by: factoryX on March 05, 2013, 01:14:09 AM