Two Stroke Motocross
Two Stroke Motocross Forum => General Two Stroke Talk => Topic started by: burn1986 on August 05, 2010, 11:29:35 AM
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I have tried to upload my proposal here buy it is too big. Here it is without any of the charts:
This proposal is to allow equal opportunity for the inclusion of 2-stroke racing machines within the AMA sanctioned Professional Motocross and Supercross events in the continental United States.
Sometime around 2005 4-strokes have been the mainstay in the AMA Pro Racing Supercross and Motocross events. In 2006, most of all factories and privateers were on 4-stroke machines. Most of the Japanese manufacturers stopped making 2 strokes in 2007 except for Yamaha. There have been attempts by riders to qualify and race in events since 2005 but to no avail. Steve Lamson attempted in 2007 on a factory prepped CR125 but did not make the top 40. Today, there are no 125 or 250 2-strokes that ever qualify for an AMA Pro National or Supercross event.
The reason a 125 or 250 two stroke cannot compare to a 250F or 450F is due to the â??spread of powerâ?. The dyno below illustrates this:
...dyno chart of YZ125, YZ144, YZ250F...
If youâ??ll notice the spread of power of the YZ250F from 4500 to 9500 RPMs is above both the 125 and 144. It is under the 144 curve for only a small amount compared to the breadth of power. This means that a 125 rider will probably never make it. By raising the displacement to 144cc the rider has a broader span of power to compete with.
The same is true for the 250 2-stroke compared to the 450F. See the charts below:
450F Chart -
...dyno chart of KTM, CRF, KXF, RMZ, YZF 450s with horsepower figures...
250 Chart
...dyno chart of KTM, CR, KX, RM, YZ 250 2-strokes with horsepower figures...
Even though the 250 2-strokes are very close in peak horsepower, the 450 Fâ??s maintain more horsepower over a wider range. This translates into more forward motion with less precision and effort from the rider. Raising the displacement to 300cc will have a similar result as the YZ144 except broadening the power over a wider range. Below is a link to raising the displacement of a 250 2-stroke to a 300cc:
http://motocrossactionmag.com/Main/News/WE-BUILD-A-KTM-300SX-BIGBORE-MOTOCROSS-BIKE-6884.aspx (http://motocrossactionmag.com/Main/News/WE-BUILD-A-KTM-300SX-BIGBORE-MOTOCROSS-BIKE-6884.aspx)
The gain in horsepower of this project raises the 250 two horsepower from 49 to 51, but it rises over the whole power curve which translates into less needed precision and effort from the rider to stay competitive with a 450F.
The main benefit of racing a 2-stroke vs. a 4-stroke is the lower cost and ease of maintenance. Listed below is an article on the comparison costs of 2 vs. 4 strokes:
http://www.lasleeve.com/galleries/2-vs-4-cost/DirtBike606-p102-104-lores.pdf (http://www.lasleeve.com/galleries/2-vs-4-cost/DirtBike606-p102-104-lores.pdf)
Pro-Circuit -
...Pro-Circuit cost chart from their website for 4 and 2-stroke motor work...
Overall, the costs of racing a 4-stroke are much higher than a 2-stroke, not to mention the actual cost of the motorcycles themselves.
Honda CRF 450 $8099
Honda CRF 250 $7199
YZ 125 $6090
YZ 250 $6990
KTM 250SX $6598
KTM 150SX $6198
Most 4-strokes are about $1000 more than 2-strokes, with maintenance and racing costs causing this figure to be more than what most privateers and smaller teams can handle. This $1000 difference will primarily fit into any big bore kit available today. Listed below is a spreadsheet with the current 2-stroke production bikes with the most widely available big-bore kits available: (Excel Spreadsheet pretty jumbled on here)
Bikes: Bike Cost /Mod. Displac/KTM parts/ GYTR/ LASleeve/Eric Gorr/MaxRPMs
KTM150 $6,198 n/a
KTM250 $6,598 300 $799.00
YZ125 $6,090 144 $859.95 $495.00
144 stroker $1,125.00
YZ 250 $6,990 265 $900.00
270 $660.00
275 $500.00
285 $600.00 $900.00
295 $600.00
TM 125 $7,499 144 $475.00
TM 144 $7,699 n/a
TM 250 $7,799 275 $550.00
TM 300 $7,999 n/a
LA Sleeve 800-822-6005, Eric Gorr 630-825-5645, Max RPMs 608-224-2524
While there is no evidence of attendance dropping in Supercross and Motocross events, the brunt of the motorcycle industry will be felt in the coming years and months. Listed below is an article on motorcycle sales from the first quarter of 2010 compared to 2009:
http://www.motorcycle-usa.com/4/7033/Motorcycle-Article/Motorcycle-Sales-Down-First-Quarter-2010.aspx (http://www.motorcycle-usa.com/4/7033/Motorcycle-Article/Motorcycle-Sales-Down-First-Quarter-2010.aspx)
2010 MOTORCYCLE SALES QUARTER 1
2010 Q1 Sales 2009 Q1 Sales % Change
Totals: 152,431 197,249 -22.7
ATVs: 56,875 76,455 -25.6
Scooter: 4,176 5,322 -21.5
On-Hwy: 66,322 84,576 -21.6
Dual: 5,309 6,020 -11.8
Off-Hwy: 19,749 24,876 -20.6
With the downturn in sales and the economy, racing and maintenance costs will continue to play a greater role with race entries, fan attendance, and factory involvement.
By allowing this rule change to allow up to 150cc 2-strokes in the 250 class and up to 300cc 2-strokes in the 450 class, AMA is offering a â??stimulusâ? to its Supercross and National programs. More and more fans and riders are switching to 2-strokes out of costs and the fun that a 2-stroke brings to riding and racing. Not only will this rule accommodate a technological and efficient race machine, it will ignite a renewed excitement and enthusiasm into a somewhat frustrated and divided fan base. Allowing this rule change will simply bring health and diversity to an already exciting and attractive racing program.
That's pretty much it so far.
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I went ahead and submitted it. Here is Al Ludington's reply:
Mark,
You have done a first rate job with your presentation. This is a text book example of how to instigate a rule change. It sure beats the hell out of calling up and screaming! I have passed the petition, proposed rule change and your documentation to my counterparts at S/X and M/X and will keep you abreast of any dialogues that come up as a result. Thanks again for the great job. Just for the record this rule change has my support. My feeling is that 4 strokes have drastically increased the price of racing and may be limiting the size and quality of our grids.
Al Ludington
Technical Director
AMA Pro Racing
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burn1986 may I say tou did an excellent job with the presentation. I know may of us want equal displacement.... but we know that will never happen, the MFG's have too much invested to let that happen. I realy like the 150/300 proposal.
Again job well done.
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Amazing. This is a lot of work to go through for anything, and it's awesome to see that someone's actually doing it!
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Major props to you Burn1986, thanks! Incidentally i think the best thing we could do to help is get your petition put up on as many websites as possible, not least of which is Rick "Super Hunky" Siemen's. 1,300 is a lot but 10,000 would be much better
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Burn, great job. You definitely did something that I should have thought of. Kudos.. I will add one thing and it is not a bang on you. But one thing you had written is that the major manufactures stopped making them. That would be incorrect. Everyone except Honda makes the same 2 strokes they did back in 2005-06. They just aren't shipped here. Yamaha is the only one shipping them. Just thought I would let you know that.
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Awesome. Great work!
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Representative Burn,
Thanks for all your hard work.
It is appreciated.
You have my vote as our first 2t representative to the Ama/Fim board. :D
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Man, that would be incredible! Maybe they will give me a brand new 2 stroke of my choice! Boy, now that would be a tough decision!
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Yes, it would be a tough decision.
WATCH OUT, Luke
the 4t dark side is lurking, they may try to corrupt you with promises of multiple 4t factory bikes....and an announcer position :o
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I like this one from Al.
It sure beats the hell out of calling up and screaming!
This is the same guy from the You Tube video screaming at a road racer privateer. I'm not sure what that poor privateer did to piss him off, but it probably wasn't good, but who knows there's always two sides to a story. If I was Al I would of never lit off like that, because yelling and screaming in someones face or on a telephone doesn't get anything accomplished. It's bad business ethics, remember Al that the AMA is a company, do the most successful companies yell and scream at their customers. NO!!
Now lets see if this rule change will happen, only time will tell. If the AMA had good business ethics they would pass this rule change no problem.
Other than that Good job Burn1986 and I really hope you get the change you want. I support it 110% because it's a step in the right direction. Keep up the good work.
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WOW!!!!! Guys are frigging hard worker!!!!Love the answer from AL this time!
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Major props to you Burn1986, thanks! Incidentally i think the best thing we could do to help is get your petition put up on as many websites as possible, not least of which is Rick "Super Hunky" Siemen's. 1,300 is a lot but 10,000 would be much better
Yeah lets spam The major websites .. even the quad guys.. Thumpertalk. etc...
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Love it ! but there is one big thing that needs to be said and that is swept volume ???? .OK here gos a 2t has a stroke that is half the length of a 4t why ? well Look into your 2t barrel you will see that half the way down is the ports this means that the power stroke is over at the point where the the ports start.Look into a 4t barrel and there are no ports this means that the power stroke is a full power stoke.there was some talk years ago that 2ts should be measured as the stroke being only from the top of the port .As you see this is a massive advantage to the 4ts and was not taken into consideration when the crack pot rules were made .
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Hmmm. Maybe they will ask for more information. I'll bet if the petition gets over 2000 they will overlook some stuff.
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Major props to you Burn1986, thanks! Incidentally i think the best thing we could do to help is get your petition put up on as many websites as possible, not least of which is Rick "Super Hunky" Siemen's. 1,300 is a lot but 10,000 would be much better
Yeah lets spam The major websites .. even the quad guys.. Thumpertalk. etc...
I'm gonna try and give the websites I've talked to an update on what is going on. Somehow, the petition has got to be spread more. I just wish a lot of the other boards (Vital, ThumperTalk, Allthingsmoto) were as motivated as TwostrokeMX.com!
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Nice write up.
Just a heads up, Lamson did make the main on his CR125 in 07. He used his former champion automatically transfer to the main card. I think he finished 37th though.
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I was wondering if I flubbed that one. I was trying to look at the results and didn't see his name so, I winged it. I should have waited for a little more feedback before submitting it. Thanks for the info.
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Yeah, gotta say that is a great effort, and hopefully we see the fruits of your labour come to fruition hopefully as soon as next year. Would be great to see even a few two strokes in each class competing and doing well. Great work.
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Very nice work, you definitely have the right idea in making conversation, and showing your idea, instead of shoving it down his throat. I would like to note though, that Jeremy Mcgrath did win one last supercross on a two stroke in 2006, I do believe. Other than that, great work! Please let me know if you need any help with this at all.
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Burn, I am very impressed with your efforts. You have done an outstanding job.
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Burn, I am very impressed with your efforts. You have done an outstanding job.
I second that.
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Burn a really awesome job you are doing.You consider running for president at all? :D
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SWEET!!! ;D
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I appreciate it. Man, I hope this thing goes through. How awesome would that be? The next battle will be for an Open class. It also sounds like the 2-stroke World Championship guy, John Perry, wants to expand to six races to coincide with the Nats if possible. And also add a 150 class and an Open class.
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Amazing!