At least one staffer has complained to the ITC about the ad campaign, which has now finished its run but is set for a re-run in July.
The staffer told BikeBiz.co.uk "I found the advert to be completely uncalled for and behind the times."
There have been 75+ complaints about the chimp ad to the ITC but the organisation has said that while the ad may not be to everybody's tastes, there could be no censure because no rules were breached.
The advert - produced by ad agency AMV.BBDO, introduced on May 21st and vetted by the broadcast advertisers clearance centre, part of the ITC - features tracksuit-clad chimpanzees drumming, caressing Ripspeed P&A, and riding bicycles. It was filmed in America.
AMV.BBDO has told the the Captive Animals' Protection Society that there were trainers and vets on site and none of the chimps were ever in distress.
However, Craig Redmond, press officer for CAPS, told BikeBiz.co.uk there has been no independent verification of this claim and that advertising agencies should already know that use of chimps in adverts is no longer acceptable.
Verity Williams, Halfords account manager at AMV.BBDO, told The Guardian:
"We thought putting the chimps in tracksuits and having the funky music soundtrack was bringing the PG Tips idea up-to-date.
"We were not getting them to act like humans and it's increased Halfords' sales. I think the broad sway of public opinion is behind us, and they think it's fun."
Redmond disagrees: "The ad is regressive, is not funny and doesn't give the products a good image. PG Tips stopped using chimps because they realised it was no longer acceptable."
CAPS has printed 5000 'On Your Bike, Halfords!' leaflets and will distribute them outside Halfords stores throughout June. Local newspapers will be contacted to publicise the 'stop using chimps in ads' campaign.
"I don't suppose Halfords will stop running the advert," Redmond told BikeBiz.co.uk.
"They would no doubt lose face doing so, but I hope it makes them think in the future, and not to use animals in their adverts.
"Our campaign has gone global. We recently had an email from a vet at primate sanctuary in West Africa, condemning the Halfords ad. I don't think the advert is doing Halfords any favours whatsoever."
The ad can be viewed from the following RealViewer site, as produced by The Guardian: