"I was winning the 15-16 years' 125cc class last year when I crashed," explained the 16-year-old, who will shortly begin racing in New Zealand's senior ranks, hopefully to follow in the wheel tracks of globe-trotting Kiwis Josh Coppins and Ben Townley.

"I ended up 13th in 2007 and that was hard to take," said Martens. But now the KTM rider is a double champion, surviving a long and arduous weekend of qualifying and racing to win both the 14-16 years' 250cc four-stroke class and the 15-16 years' 125cc two-stroke class as well.

"I guess my luck changed this year. I was disappointed it rained because I don't ride well in mud but I got my head around it and stayed upright," said Martens.

It was hard work, though, with the defending champion from Wellington, Henry Madams (KTM), and Rotorua Kawasaki ace John Phillips pushing him all the way in the 250cc category and Cambridge's Kieran Leigh (Yamaha) and Central Hawke's Bay's Kieran Scheele (KTM) challenging hard in the 125cc class.

The cream of young Kiwi motorcycling talent flooded into the King Country over Anzac weekend -- more than 365 riders -- for the annual event, which has now grown to a four-day affair.

Jointly sponsored by KTM and Kawasaki, the national championships featured racing in seven separate age-group and bike capacity classes, with seven races in each category.

Overcast but dry on Saturday, a downpour turned the track into a quagmire on Sunday, but the skies cleared again on Monday and this meant the spectacular hillside course offered the best and worst of riding conditions and tested riders to the limit. In the younger age groups, Rangiora's Isaiah McGoldrick (KTM) won the 12-14 years' 125cc class, ahead of Christchurch rider Craig Smith (Honda), with Wanganui's Tom Managh (Suzuki) in third, while Marton's Michael McCarthy won the 12-16 years' 150cc class from fellow Honda riders Stuart Young (Napier) and Cody Rickit (New Plymouth).

Mangakino's Kayne Lamont led a Yamaha 1-2-3 in the 13-16 years' 85cc class, beating Tauranga riders Roydon White and Logan Blackburn to the trophy.

Aucklander Brandon Tipene (KTM) won the 11-12 years' 85cc class from Feilding's Haki Waller (Kawasaki) and Atiamuri's Hadleigh Knight (KTM).

Balclutha's Matt Whaanga took his RM85 Suzuki to the top of the 8-10 year's class, beating Levin's Billy Frank (KTM) and Oamaru's Joel Meikle (Honda) to the finish.