Cycling Southland president Reece McDonald is "doing well" on his seventh Westpac Chopper Appeal Bike Ride only six weeks after having a heart attack.

The 54 cyclists making the day-long, 235-km bike ride from Queenstown to Invercargill for a good cause are enjoying sunny skies and no breezes as they head into Invercargill this afternoon.

But according to bike ride organiser Murray Heath, the conditions have been particularly welcome for Cycling Southland president and long-time bike ride participant Reece McDonald, who had a heart attack only six weeks ago.

Mr Heath said Mr McDonald was one of three of this year's riders who had used rescue helicopter services recently for medical emergencies.

Mr McDonald had been medically cleared for the event and was "doing well."

"He went for a 100km ride last week and felt it's really tough, but... the sun on your back and no breeze makes a hell of a difference," Mr Heath said.

"He now knows that what he's been preaching is actually true, that you need a chopper."

The Southland App caught up with Mr Heath during a well-deserved lunch break at Takitimu Primary School.

He said conditions for the ninth annual bike ride started off black, cold, and foggy as the riders headed down the Devil's Staircase this morning.

But by the time they reached Five Rivers in Northern Southland, the sun had been out and made for a great day of riding.

The bike ride supports the month-long Westpac Chopper Appeal, with all funds raised by the ride going back to the Lakes District Air Rescue Trust. 

As of 2.30pm today, more than $13,600 had been raised through the bike ride's Givealittle page. 

During the cyclists' stop at Takitimu Primary School, students also got a surprise visit from a rescue helicopter and got the chance to check it out. 

After lunch, the riders were headed to the Drummond Golf Course before finishing their journey in Invercargill. 

According to the event's Facebook page, the group was making great time and "should be home by 4.30pm."