WHAT IS IT? An exhaust system makes the KTM 250SXF the fastest bike on the track.
WHAT’S IT COST? $999.95 (Ti-4R), $899.95 (Ti-4GP), $779.95 (T-4GP stainless).
CONTACT? www.procircuit.com or (951) 738-8050.
WHAT’S IT DO? The 2009 KTM 250SXF pumps out 38.6 horsepower in stock trim (the 2010 model makes less horsepower because it uses the more restrictive EXC muffler). Yikes! That is powerful. For comparison, that is at least one horse more than an 2009 RM-Z250, KX250F, CRF250 or YZ250F. Even more impressive is the 2009-2010 KTM’s over-rev. Unlike any other 250 four-stroke, the KTM comes close to making its peak horsepower at its peak rpm. That means that as long as the engine is revving, it is making power. The KTM’s peak horsepower is 12,800 rpm.
WHAT STANDS OUT? Here’s a list of things that stand out with Pro Circuit’s KTM 250SXF Ti-4R exhaust system.
(1) Performance. The 2009-2010 KTM 250SXF makes the most horsepower in the 250 class for 2009 and 2010, but that doesn’t mean it has the best powerband. KTM has focused all of the 250SXF’s power in the upper end of the range. From 9000 rpm up, the 250SXF just keeps on rumbling. It’s not much to write home about below 9000 rpm, but after that it is incredible. It pulls and pulls forever. Best of all, it never signs off or goes flat. It is the only powerband in the sport that revs to 13,500 and is still making power until the rev limiter kicks in. Bolting on the Pro Circuit Ti-4R doesn’t add any bottom, doesn’t beef up the hit, and doesn’t make an iota of horsepower more from idle to 9400 rpm. But after that, hold on to your hat. This pipe rips from 9400 to 13,500 rpm. Nothing can touch this pipe or this bike on the top end. No need to shift (although if you want to, the KTM 250SXF has six speeds). Pro Circuit can push that stock 38.6 horsepower up to 40 horses, move the peak even higher, and fill out the top end.
(2) Materials. The Ti-4R is Pro Circuit’s full-race, factory replica National pipe that spares no expense. It is a thing of titanium beauty, but the $200-cheaper stainless steel T-4GP has all the same dimensions and horsepower.
(3) Sound. Kudos to Pro Circuit. They vowed that every one of their exhaust systems would meet or beat the AMA/FIM sound limits. True to their word, the KTM 250SXF Ti-4R exhaust passes the AMA’s 94-decibel sound test. Beating the 92 dB's of the 2010 models enduro muffler is not in the cards, but the Pro Circuit pipe is still AMA legal,
(4) Mounting bracket. Pro Circuit has developed a stronger aluminum mounting bracket to hold the muffler body to the frame (they had previously used a welded-on Ti bracket that was prone to cracking).
(5) Place of Manufacture. Pro Circuit’s Ti-4R exhaust is manufactured in Corona, California.
WHAT’S THE SQUAWK? Two complaints: (1) The price. (2) Be sure to apply the included antiseize grease at midpipe junctures. Otherwise the system becomes difficult to separate after it heats up.
It is hard to imagine that a local racer could own a 250cc four-stroke that pumps out 40 horses. The Pro Circuit Ti-4R makes the dream a reality.
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