TransLink is promising to investigate a tolling glitch on the Golden Ears Bridge that has been overcharging some commuters.

Motorcyclist John Waddington used to cross the bridge regularly without thinking twice about the toll that's charged automatically to his credit card.

That all changed when he received an email from a fellow rider urging him to check his invoices. He discovered numerous crossings where he was charged almost $2 extra; the tolling system had confused his motorcycle with a car.

One invoice showed errors on nine out of 12 crossings. He was eventually reimbursed, but only after lodging a complaint.

"That didn't sit well with me," Waddington said. "They've known since at least April, and probably more than that, that their machine was not accurately recording the passage of a motorcycle but they didn't give us a credit until we asked for it."

TransLink says the system is supposed to be accurate 97 per cent of the time. Spokesman Ken Hardie promised the issue will be looked into by the tolling contractor on Monday morning.

"It's clearly something we expect them to fix as per our agreement with them," he said.

Arnie Tucker says he has also been regularly overcharged when crossing the bridge. He showed CTV News his last bill. "Eight out of 14 they billed me for a car," he said. "More than half."

And Tucker says the mistakes date all the way back to his very first bill. "They haven't corrected the problem," he said.

Waddington says motorcyclists need to start diligently checking their bills – they may have been paying too much.

With a report from CTV British Columbia's Chris Olsen