2-Stroke MX Nationals Rule Clarification

KTM Australia’s General Manager Jeff Leisk has clarified the details and effects of recent rule changes to the MX2 and MXD categories of the 2015 MX Nationals.

Put very simply, the rule states that two-stroke engines in those two classes must be stock standard between (but not including) the carburettor and the expansion chamber. The only exception is that an extra base gasket can be added for extra squish clearance on heavier tracks.

“These production rules,” says Leisk, “say the bike must remain in stock trim from the intake manifold to the exhaust port, and all engine parts between those two points and must be OEM for that year model. You can have a different carburettor and exhaust, and you can add a base gasket to increase the squish clearance on a sandy track so your bike doesn’t run too hot.

“In case people were holding back though, or thinking they couldn’t race their two strokes next year, the thing to highlight is that the actual rules in the MA rulebook do not change. So if you are a local or state level racer for example, you can still do whatever you want – this is just for the MX Nationals.”

So does Leisk believe that – apart from making a cheap access to top-level racing even cheaper for the competitor – these changes will make any significant difference?

“I don’t believe so,” He says.  “I’m very confident in the production cylinders, heads and intake on a KTM, and in my opinion, nine times out of 10, people modifying the barrel basically destroy the good hard work that the factory has done. So do I have a concern? Not at all, in fact I think it might save some people from actually making their bikes go slower. A lot of tune jobs actually tend to slow them down, that’s my experience over the years anyway!

“We are very confident that the KTM is tuned to the highest levels anyway and Ready to Race straight out of the box, so there will be no negative aspects to riding a two-stroke in the MX Nationals.

“Why did they have to do this? I suppose they have had to react to, well basically other manufacturers. I think most of the other competitors were actually okay with it. So that’s something that Kevin (Williams – series owner) had to do to appease the other manufacturers. They’re funny these guys, they never complained when the 250 four-stroke was up against a 125 two-stroke, or a 450 was up against a 250 two-stroke, they never felt sorry for anyone then!”

Naturally you’ll still see plenty of KTM two-strokes in MX Nationals competition next year, as well as at least one factory-backed rider to prove that KTM’s 250 SX-F is just as competitive.

“That’s the beauty of KTM as a brand,” remarks Leisk, “we offer everything. We offer the most options for an off-road rider, period, whether that be four-stroke, two-stroke, 50, 65, 85, 125, 250, 350 or 450.”

KTM's two-strokes: Ready to Race straight from the box.
KTM’s two-strokes: Ready to Race straight from the box.

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