BANGKOK, 12 Jun 2015 (AFP) - Only a bogey on 14 stopped Jazz, who turns 20 in November, from taking the outright lead from Kim, as South Korean golfers continued their strong run at the $1 million event.
Kim plundered five birdies on the front nine and eight in total to return to the clubhouse with a flawless 64.
A first round 71 had not however suggested he would storm into contention for the joint-sanctioned OneAsia and Japan Golf Tour Organisation title being played at the Thai resort city of Pattaya.
On a day when the threat of summer storms interrupted play, China's Zhang Xin-jun finished a shot back on eight under after an uneven round that featured two bogeys, an eagle and a string of birdies.
Namchok Tantipokhakul was also a shot off the lead after an impressive 66, with his fellow Thais matching the Korean charge.
Local hero Prom Meesawat, who hit a 69 on day one, made five early birdies but was a late finisher after the delays.
Also in the mix was Kiradech Aphibarnrat, whose 68 -- lit up by an eagle on the par five second hole -- put him just three shots off the lead.
Overnight leader Kim Hyung-Song hit a double bogey at 11 in a rain delayed round to draw him back into the pack after an impressive first round 65.
Meanwhile, Thailand's Panuphol Pittayarat, who started the day with a 66 under his belt, blundered to a second round 74 with five bogeys.
Leading scores from the weather-hit second round at the co-sanctioned OneAsia/Japan Golf Tour Organisation Thailand Open in Pattaya on Friday.
135 - Kim Kyung-tae (KOR) 71-64, Jazz Janewattananond (THA) 69-66
136 - Zhang Xin-jun (CHN) 71-64, Namchok Tantipokhakul (THA) 70-66
137 - Lee Kisang (KOR) 69-68, Yasuki Hiramoto (JPN) 72-65, Danny Chia (MAS) 69-68, Song Young-han (KOR) 70-67
138 - Kim Bi-O (KOR) 68-70, Mu Hu (CHN) 71-67, Kiradech Aphibarnrat (THA) 70-68