Two Stroke Motocross
Two Stroke Motocross Forum => General Two Stroke Talk => Topic started by: Rota Ash on April 12, 2010, 02:36:26 PM
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Hey i was just wondering if it's even possible to take down a 300 with a 250 motocrosser, what would need to be done to a 250 to keep up with a fairly worked 300, say pipe's and reed valves on it, would u be wasting your time trying to beat a 300 in a beach drag race ???
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I'd see if it could be bored/stroked to 300+. A lot of bikes we know and love are bored versions of bigger bikes. Taking from what I know, meaning Maico, the 490 was a bored 440, which was a bored 400. They all shared the same stroke, and the rest of the engine (transmission, clutch, etc.) was virtually the same. Even the new 320 is just a bored-out 250.
Sure, you wouldn't have a 250 anymore, but that's what I would do if I had to challenge a 300 with a "250."
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Depending on what brand 250 your talking about?If your referring to the KTM-250sx or xc Ktm makes 300 heads for those bikes.If your referring to a Japanese brand I would look into geting it bored. 8)
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so pretty much no replacement for displacement is what you are getting at. a 250 will never beat a 300 ?
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In a drag race... there is now replacement for displacement... the 300 will beat the 250 as long as the riders are of equal ability. Of course the better rider on the slower bike will end up beating the slower rider on the faster bike...
Sorry, can't think of another way to say the same thing! LOL ;D ;D
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Well, I guess I should do my duty and list some off-the-wall options to winning the drag.
- Nitromethane is a universal cure to all the world's problems. You'll probably need to rework all of the jets in your carb and who knows what else to accommodate the massively increased fuel flow, but when you get it dialed in the bike is going to be on a mission to head-but the horizon.
- When shifting, don't even ponder the possibility of conceiving of an alternate universe in which you think about using the clutch. All it's going to do is slow you down, and if you let off the power, a bike with a decent transmission will shift smooth as butter without any intervention by the clutch.
- Add some underglow, a bodykit, and a huge spoiler if you've got a Honda. I hear that these modifications alone can add as many as 300 horsepower to a Civic, so it may help your bike!
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haha good post ;D would be good to beat a 300 with a 250 in a drag tho just for bragging rights haha. but with 15% more capacity it would be hard to make that up in hp.
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Hey i was just wondering if it's even possible to take down a 300 with a 250 motocrosser, what would need to be done to a 250 to keep up with a fairly worked 300, say pipe's and reed valves on it, would u be wasting your time trying to beat a 300 in a beach drag race ???
if you are talking about a stock KTM 300 xc and a KTM 250 sx the 250 has more hp and a more radical state of tune. the mx bike will have much lower top speed due to being geared for a track.
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im talkin ktm 300 with stocko motor stock jetting but pipes and a reed valve assembly, seems to be alot of them out there with just bolt ons, vs a ktm 250 jetted ported with pipe's and reed valve assembly (v force or rad valve) with equal riders in a drag race
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I'm gonna go out on a limb here. First, it's not possible to have equal riders per say. Even at the top, there are some who can holeshot and some who can't. If we are talking a roll on, I'd say the 300, but other than that. I smoke 450F's all the time on holeshots. So am I a better rider? Probably not, but I can run my 2 stroke at wide open from the line, while they are keeping their front end down etc. So I honestly don't think there is a perfect answer for your question. ??? Sorry, JMHO
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im talkin ktm 300 with stocko motor stock jetting but pipes and a reed valve assembly, seems to be alot of them out there with just bolt ons, vs a ktm 250 jetted ported with pipe's and reed valve assembly (v force or rad valve) with equal riders in a drag race
i've dyno'ed two 300 KTM's. both produced 45 hp in stock trim but had a couple more ft. lbs. of torque in the middle rpms over a 250SX. but in shear hp the 250SX kills it with an average of 4 more hp. most bolt on stuff moves the power around rather than increases it to any degree, at least that's what i see on the dyno. Miedosoracing is correct with his post. i used to drag race alot and getting what power you have to the ground resulting in forward motion is the key. a less powerful bike can beat a big power one with a better rider.
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The Challenger - 3 HP Briggs and Straton 2 stroke side shaft
The Champ - KTM 300
What can we do to the briggs to have it beat the KTM?
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How about....
(http://image.hotrod.com/f/9802510+w750+st0/hrdp_0308_01_z+briggs_and_stratton_engine+combustion.jpg)
:o :o
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sorry i didn't think it was that silly of a question, seeing in the car world a 308 cubic inch motor built right can easily beat a modified 383 in the same weight car didnt think i was comparing a gsxr1300 to a ride on mower
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In all seriousness, it's certainly possible to with with smaller displacement, even using the same configuration (two-stroke, four-stroke, whatever) and fuel and all that. For example, in 1971 they made a rule in NASCAR that if your car had a wing on it (in other words, if it was a Dodge or Plymouth) then it'd have to run a 5L engine instead of a 7L engine like the rest. One man showed up with a Dodge Daytona, and was quite competitive with his 305 turning 10K against the more conventional 429s and non-winged 426 Hemis. I gather it just didn't quite have the reliability to run for the hours required of a stock car, though.
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sorry i didn't think it was that silly of a question, seeing in the car world a 308 cubic inch motor built right can easily beat a modified 383 in the same weight car didnt think i was comparing a gsxr1300 to a ride on mower
The photo posted above was in response to opfermanmotors post about the Briggs thing..
You are correct, there is more than displacement that win determine a winner in any kind of race. The rider is the most important aspect of that equation. Ability, talent and preferences all come into the final test of which is best. If you are a 125 two-stroke maniac, love the bike and have trained yourself to use it to it's best potential, then you can drag race 450F's to the first turn of the motocross race and beat them, as I have seen before in the Expert class...
To get back to your initial question, which is faster a 250SX or a 300SX, there is no one answer that takes every variable into consideration. You might be able to race a stock 250 against a 300 and beat it, or depending on the rider you could have a highly modified 250 that would not beat a stock 300.
Really I'm not trying to be funny at all... there are just too many variables to answer that intelligently and with authority.