Crankworx 2016 delivered about $8 million into the Rotorua economy - a $4.2 million increase on last year's event.
The mountain biking festival drew about 10,000 visitors to the city when it was held for the second time in Rotorua in March.
The main events took place at Skyline Rotorua Gravity Park on the slopes of Mt Ngongotaha and in the Whakarewarewa Forest.
An economic impact assessment of the 2016 event, produced by Rotorua's APR Consultants, will be presented to the Rotorua Lakes Council tomorrow during a meeting of the council's Operations and Monitoring Committee.
According to an agenda report the council committed to underwriting the event with $94,000 spent in 2015, dropping to $39,000 this year.
The APR report stated a total of $8 million was added to Rotorua's economy - $5.8 million from domestic visitors and $2.2 million from international visitors. This figure was up substantially from last year's total of $3.7 million.
A total of 15,439 people attended - almost 90 per cent from New Zealand - with 94.3 per cent of those surveyed saying they would return for Crankworx 2017.
"Overall, the total number of visitors to Rotorua whose main reason for visiting was to attend Crankworx as a spectator is estimated to have increased from 3696 people in 2015 to 9344 people in 2016," the report said.
Crankworx director Tak Mutu said everyone was "really stoked" with the result.
"The mission is to keep up that momentum. We need government support for the event to keep it growing as it needs to build on itself from year to year, it can't just be the same thing each time."
He said he was in negotiations for an extension to the Crankworx contract for 2018 and beyond.
Rotorua Chamber of Commerce chief executive Darrin Walsh said the report was great news .
"We all said after year one it would take two or three years to hit its straps. I think this year we all noticed there were more people at the event and around town. On that basis it was a huge success, that's $8 million we would not be getting if it wasn't on."