* Bidders extend offer to Sept. 11
* No rush to sell non-core assets - sources
* New group will refocus on Kazakh assets - sources
By Clara Ferreira-Marques
LONDON, Aug 29 (Reuters) - The founders of troubled Kazakh miner ENRC, leading a $4.8 billion bid to take the company private, said on Thursday a majority of small investors had backed the offer, taking acceptances to 94.5 percent.
That all but guarantees success for the trio of billionaires who founded ENRC, as they prepare to refocus the group on its core Kazakh ferroalloy and iron ore operations, slash debt and reverse a $6 billion expansion drive into Africa and beyond.
Taking ENRC private will draw a line under six turbulent years for the group as a London-listed firm, plagued by boardroom rows, corporate governance concerns and corruption investigations.
Sources with knowledge of the matter said on Thursday the bidders would move key administrative functions to Kazakhstan and refocus ENRC on ferroalloy and iron ore assets there as well as operations in the Democratic Republic of Congo - the heart of potentially lucrative African copperbelt assets that the founders intend to keep.
But they would not rush into a firesale of costly development assets that include a greenfield coal project in Mozambique - close to Rio Tinto's problematic Riversdale asset that triggered an almost $3 billion writedown earlier this year - and an iron ore project in Brazil, the sources said.
ENRC's new owners will seek to cut back the company's hefty $5.5 billion debt burden. But there was little pressure for that from lenders funding the bidders themselves - the trio have not yet received any cash, one of the sources said.
"They will have quite a few things to deal with when they take over. Selling the assets isn't going to be the first thing they will do," the source said.
Miners have put billions of dollars of non-core mines and projects on the block, but sales of all but the most coveted assets have been slow, as sellers hold out and buyers focus on key commodities, seeking bargains.
The trio of billionaire founders, Alexander Machkevitch, Alijan Ibragimov and Pathokh Chodiev, working with the Kazakh government, already had the support of ENRC's largest shareholder, rival Kazakhmys, after a vote this month.
They said on Thursday, after the first deadline for acceptances on Aug. 28, that small shareholders accounting for 14.6 percent of stock, had also taken up the offer.
Including a 26-percent stake held by Kazakhmys and almost 54 percent held by the government of Kazakhstan and the founders themselves, that takes acceptances to 94.5 percent.
The buyout deal is still awaiting final antitrust clearance. Remaining shareholders have until Sept. 11 to accept the bid.
The offer, $2.65 in cash plus 0.23 of a Kazakhmys share for every ENRC share, is worth about 241 pence per share at current prices. ENRC shares were trading around 227 pence on Thursday.