Not every rider is alike. There are riders who like the snap of a 250cc
two-stroke, those who prefer to wring the guts out of a wide-open 125cc
tiddler, and a third group that craves the abundant vibes of a 250cc
four-stroke. The MXA wrecking crew decided to round up all three of
these bikes and compare them head to head. Now, you might be wondering
why we didn’t include a 450cc four-stroke in the comparison. The answer
is simple: very few riders are trying to decided between a 450cc bike
and a small-bore racer. They know that they want the big dog, and the
normal 450cc shootout will answer all their questions. This isn't the place. But, lots of
former 250cc four-stroke pilots are now thinking about two-strokes. So,
the relevant comparison is a 250 four-stroke versus a 250 two-stroke or a
We must admit that this isn’t really a shootout in the
purest sense of the word. In a true-to-life shootout, you compare each
bike’s merits, analyze where it ranks in relationship to the other bikes
in the test and crown a winner. We aren’t going to do that.
We must admit that this isn’t really a shootout in the purest sense of the word. In a true-to-life shootout, you compare each bike’s merits, analyze where it ranks in relationship to the other bikes in the test and crown a winner. We aren’t going to do that. There is a paradox involved in going through all the steps of a classic three-bike shootout and then not actually picking a winner, but the truth is, these three bikes are so different that personal peccadilloes play a bigger role in choosing the winner than actual performance.
Instead of doing a classic shootout, we have developed the Motocross Action Multiphasic Inventory Quiz (MAMIQ). When this test is used by trained professionals, like the MXA test crew, it helps identify personality traits, psychopathological needs, financial stability and clinical analysis of a rider’s ability to handle each machine.
DO YOU WANT THE CHEAPEST NEW BIKE?
If price is a concern, then the KTM 125SX is the most
appealing. The KTM 125SX comes in at $6449.00. That is $650 cheaper than
the KTM 250SX’s $7099.00 price tag. The price gap between the 250SX and
the 250SXF is around $400. It should be noted that the KTM 250SXF is
the most expensive 250cc four-stroke of the Big Five. However, the KTM
250SX two-stroke is still cheaper than the YZ250F, KX250F, RM-Z250 and
DO YOU WANT A BIKE THAT REVS TO THE MOON?
Nothing—and we mean nothing—revs as high as a KTM 250SXF four-stroke. Its 14,000-rpm rev limiter puts every other bike to shame. No need to shift on a bike that revs higher and farther than any bike made—just slam it into a gear and hold it wide open. It should also be noted that the KTM 250SXF four-stroke makes its peak horsepower well after 13,000 rpm, which means that if you don’t rev it to the moon, you won’t maximize its powerband.
ARE YOU LOOKING FOR THE MOST MIDRANGE BURST?
Do you like to work the engine in the meat of its powerband? Forget about the KTM 125SX and KTM 250SXF; they have unique powerbands. But, when it comes to midrange monsters, they can’t compete with the KTM 250SX two-stroke. You don’t need a calculator to realize that at 8000 rpm, the 250SX two-stroke makes 19 more horsepower than the 250 four-stroke and 28 more horsepower than the 125 two-stroke. Those numbers may sound inaccurate, but believe us, they are true.
DO YOU WANT THE BEST ALL-AROUND POWERBAND?
Want to buy the bike that has the best all-around powerband? In that case, choose the KTM 250SXF. It has the broadest powerband of the three bikes. But wait, didn’t we just say that the KTM 250SX made 19 more horsepower than the 250SXF four-stroke? Yes, we did, but that was just a snapshot at 8000 rpm. By 10,000 rpm, the 250SXF and 125SX are both making twice as much power as the 250SX. And if you push the rpm to 11,000 rpm, the 125SX tiddler and 250SXF thumper are making 29 and 40 horsepower more than the 250 two-stroke. The 250SXF has a long and broad powerband that comes into its own around the middle and keeps on pulling after that.
DO YOU WANT THE MOST HORSEPOWER?
Everybody loves horsepower. It makes the wheels go
’round. The KTM 250SX two-stroke peaks out at 49.77 horsepower (at 8500
rpm). The KTM 250SXF four-stroke makes 42.88 horsepower (at 13,500 rpm).
The KTM 125SX two-stroke makes 34.66 horsepower (at 11,200 rpm).
DO YOU WANT THE LIGHTEST BIKE?
The weight difference between each bike is phenomenal. The KTM 125SX weighs 206.5 pounds, which is almost 10 pounds lighter than the 250SX and over 24 pounds lighter than the 250SXF four-stroke. The three bikes weigh 206.5, 216 and 231 pounds respectively.
HOW MUCH DO YOU WEIGH?
Sorry if we are getting personal, but 125cc two-strokes work best in the hands of aspiring jockeys—although they can work well for riders up to 160 pounds. A 250cc four-stroke can carry a burden of around 185 pounds, but prefers lighter loads. Thus, if you weigh over 185—and especially if you weigh over 200 pounds—you should be thinking 250 two-stroke (or 450 four-stroke).
ARE YOU INTERESTED IN THE BEST-HANDLING BIKE?
Because of its steady vibes, even though it’s heavy, the KTM 250SXF four-stroke handles better than the 125SX or 250SX (except in the hands of the talented). It is not quicker or more agile, just more predictable.
ARE YOU LOOKING FOR THE BEST SUSPENSION?
You’re in luck, because these three bikes all suffer from the same suspension woes. The MXA test crew subscribes to the theory that lighter bikes with less power put less load on their forks and shock than heavier, more powerful bikes. We may subscribe, but that doesn’t make it true. We had issues with all three. If we weren’t talking about KTM suspension, you could easily assume that 125s have the best suspension, 250 four-strokes the next best and 250 two-strokes the hardest worked.
DO YOU WANT THE BEST BRAKES?
This is another category where the three KTMs—125SX, 250SX and 250SXF—share the same parts, but unlike with handling, the weight of the bikes does make a difference in braking power. KTM’s 260mm Brembo front brake is powerful enough for a 240-pound, 56-horsepower 450SXF, so you don’t need much in the way of imagination to know how powerful that same brake is on a 206.5-pound KTM 125SX.
ARE YOU LOOKING FOR THE MOST RELIABILITY?
The simple fact that the three bikes in our test share
the same rolling chassis, brakes, suspension components, plastic,
levers, wheels, controls and accoutrements means that reliability comes
down to the engine’s top end, tranny and clutch. Barring catastrophes,
the KTM 250SXF four-stroke will prove to be the most reliable. Note that we staid "Barring catastrophes." It will
require less in the way of pistons, rings, gaskets and clutch plates
over a "single" racing season than the 250SX or 125SX.
The caveat is that, in the case of a major blowup, the 250SXF four-stroke will become a financial burden. Whereas the 125SX and 250SX can be repaired in the garage with a couple hundred dollars worth of parts, the 250SXF four-stroke will quickly crack $1000 in parts and come with a big labor bill (for the mechanically inept).
WHO SHOULD BUY A KTM 125SX TWO-STROKE?
According to the Motocross Action Multiphasic Inventory Quiz (MAMIQ), the KTM 125SX is best suited to a rider who:
Is new to the sport and wants to learn the ropes. A 125 teaches throttle control, clutch use, effective shifting and maintaining momentum. It is easier for a beginner to handle because it is lighter and less powerful. A quick survey of former AMA Pros reveals that they almost always start their youngsters out on 125cc two-strokes before letting them move to bigger and heavier bikes. Why? Because they want their kids to learn how to ride before moving them to more complicated machinery, and you learn faster and more thoroughly on a 125 than any other size bike.
Has been around the sport for a few years and has been burned out by the cost of 250cc four-strokes. Many 30-something riders return to 125cc two-strokes to reinvigorate their interest in motocross. However, once a rider gets to be about 40, the 125 two-stroke places too many demands on the rider. Additionally, really fast riders, like Pros and former Pros, aren’t good candidates for 125s. Their egos can’t take losing to a rider they could beat if they were on a big bike. Pros like to ride 125s for fun, but not if there is serious work to do.
Rides with total abandon. There is no strategy in riding a 125cc two-stroke. You pin it, keep it pegged and try not to shut off. You can’t trail ride, putt around the track or cruise on a 125.
Races on tracks with lots of tight turns—and stays away from big hills, long starts, sand, loam or smooth tracks.
Is small, light or just getting off of a minicycle.
WHO SHOULD BUY A KTM 250SX TWO-STROKE?
According to the Motocross Action Multiphasic Inventory Quiz (MAMIQ), the KTM 250SX two-stroke is best suited to a rider who:
Likes a strong midrange hit—and doesn’t need any low-end whatsoever. This bike rewards a gun-and-run approach to the track. Go in hot and come out hard.
Gets good starts. If you are racing a 250 two-stroke against 250 four-strokes and 125 two-strokes, there is no way that anyone will ever beat you to the first turn. That’s where that 19 extra horsepower at 8000 rpm comes into play.
Is creative. As a rule of thumb, 125 two-strokes and 250 four-strokes have to race on the prescribed “good” line. Not so with a 250cc two-stroke. It is light enough to jam to the inside and blessed with quick and snappy power to make big cuts work. A 250 two-stroke can go places that a 125 or 250 four-stroke could never go—for fear of bogging or losing momentum.
Can hang on when the going gets tough. A 250 two-stroke feels fast, reacts fast and wears the rider out fast. Going fast on a 250 smoker is like riding an exercise machine. The burst of acceleration pushes you back in the saddle, while the hard braking drives you forward. A good 250 two-stroke rider is fit as a fiddle…or slow.
Doesn’t mind being on a bike that isn’t status-backed by the mob majority of the moto world.
Is a typical mesomorph—stocky, strong and aggressive.
WHO SHOULD BUY A KTM 250SXF FOUR-STROKE?
According to the Motocross Action Multiphasic Inventory Quiz (MAMIQ), the KTM 250SXF is best suited to a rider who:
Thinks he is only one win away from making the big time. If you race a two-stroke, the factory scouts for the big teams will discount your performance. To get a factory deal to race a 250cc four-stroke, you need to be racing a 250cc four-stroke.
Wants the easiest-to-ride powerband.
Is looking for an engine package that bridges all the gaps—quick, broad, easy to use, foolproof and hooked up.
Races on tracks that have off-camber corners, sweeping transitions and very few stop-and-start corners (and, especially, concrete starting pads).
Is willing to race a bike without knowing how to fix it.
Doesn’t want to rock the boat, be different or try new things. After all, because of the displacement rules, modern racing organizations favor 250 four-strokes.o