Lahiri, who shot eight-under 63 in the first round, was one-under through nine holes with three birdies and two bogeys.
Danny Willett (69-67), Victor Dubuisson (68-65) and Stephen Gallacher (five-under through 12 in second round) were at nine-under alongside Lahiri.
Shiv Kapur ensured he would play the weekend rounds with cards of 70 and 69, while Gaganjeet Bhullar, who shot 68 in first round, was one-over through 13 holes in second, and was two-under for the tournament, where the cut looks likely at even par.
SSP Chowrasia (73-71) looks likely to miss the cut at two-over and going out with him would be C Muniyappa (71-74) at three-over. Himmat Rai and Digvijay, who are yet to complete their second round are at four-over and five-over respectively and will certainly miss the cut.
