Gate said he had an "absolute ball", telling race director Steve Stannard he was not wrong when Stannard said it was a fun race to do.
Gate said there was a bit of banter and some cat and mouse during the four-plus hour race.
It was not an easy race to win and he had to empty the tank to cross the line first.
In 2012, Gate collected a bronze at the London Olympics in the men's team pursuit (4000m).
As its name suggests, Gravel and Tar takes in gravel roads in rural Manawatū.
Stannard said it was a pretty tough day for everyone, probably the hardest 160km the riders were going to do for a while.
He said anyone who finished the race had done well.
Luke Mudgway, also from Black Spoke Racing, was second.
The former Palmerston North Boys' High School student came in second last year as well and in 2019 he was the winner.
Mudgway said the extra 30km hurt a lot - the gravel was brutal and the climb hard.
Gusts of wind meant he had to always be attentive.
Riders had to take into account a lot of elements and had to keep going a kilometre at a time.
NZ National Team rider Ryan Christensen was third.
The winner of the Gravel and Tar La Femme was Olivia Ray, of the NZ National Team.
In second was her teammate Sharlotte Lucas and third was Rylee McMullen, of the Andy Schleck team.
Ray has ridden professionally in the United States and is the current national criterium champion, while Lucas is an Oceania road champion.
The women's race was 86.7km.
La Femme is the only women's UCI (Union Cycliste Internationale) road race in New Zealand and it includes about 30km of gravel sections.
In his welcome message to cyclists, Palmerston North Mayor Grant Smith said considering the significant impact of Covid-19 on cycling events, "it's a real credit to the determination of the race organisers" the event happened.
Now it its sixth year, the race is gaining a reputation as one of the hardest single-day races on the international calendar, Smith wrote.