"The intent of the plan was not to see this as a mountain bike park," he said.
"It was around creating connections between different parts of the suburb, so people can obviously walk through the connections, but also people cycling could cycle through those interconnections without solely being on the urban street."
Track mitigation is underway at Tainui, to slow bikers onto shared tracks and discourage riding on pedestrian-only tracks, but Maxwell said some were less than courteous.
She is co-ordinator of Friends of Tainui, a local group that liaises with council over park issues. She said mountain biking was the biggest issue it had dealt with.
"I've had a lot of feedback and there have been letters in the paper and the people tell me that they feel unsafe and also when they come to the reserve they feel on edge," Maxwell said.
"That's because they are looking out for wayward bikers, coming around paths that they shouldn't be on. And also they fear for their dogs' safety because the council lawyer advised that, if a biker hits a dog, the dog owner would be held liable."
Bennelong Mountain Bike Club spokesman Richard Mills said he was surprised and disappointed at the negativity towards sharing Tainui Reserve.
"I guess if you don't understand mountain biking then you could have some concerns for safety," he said.
"These machines that we generally ride now stop as quick as anyone walking or running. Going up a hill at Tainui Reserve you're going as quick as a walker or a runner or a dog anyway."
He said downhill riding could be a safety issue but there were ways to mitigate the risk, with some mitigations currently underway.
Park Biker Mike Taylor said he was surprised there was no uphill track, riders had to dismount.
"I would ride up that on my e-bike, so the logical thing to me would be to build an uphill track for the mountain bikers.
Park walker Robin Bell said human behaviour was the problem, not track design, with errant bikers already scaring off some park users.
"I was here two weeks ago and walked all the walks in Tainui. I saw one biker on a biking-only track, every other biker I saw was on a walking-only track.
"The bikers are taking French leave and saying, we can go wherever we like in Tainui, and that's the end of the matter. That destroys the reserve for other users, in particular walkers."
He said mountain biking in Tainui Reserve was "a failed experiment" and heavy riders versus fragile walkers on steep and narrow paths was a serious safety issue.
"I think it should be recognised as such and terminated before someone gets seriously hurt or even killed."
But not all park users agree. Park walker Tony Wrightson said he was "absolutely supportive" of sharing the park with mountain bikers.
"I think they are absolutely entitled to use this landscape," he said.
"If they can be separated and that can be managed well then that's fine with me."
Park walker Pauline Hayes said the park was still a wonderful place to walk her dog.
"It's a beautiful park and there's plenty of it and I've never encountered any problems," she said.
"I walk the dog here a lot. It's great - a good thing."
Park walker Simone Tang said "as long as the main tracks are separate to the walking tracks, I don't have a problem".
Bikers making most of their new access to the reserve insist, that used responsibly, the tracks are a positive addition to the community.
Park biker Steve White said mountain biking keeps him active alongside his teenage son "in the part of his life when he wants to abscond from his parents".
"He actually stays close to me and we can bike and do something together. We both love it - it's really good," he said.
He said he was teaching his son to be respectful of other riders and walkers "and I think the two of us can get along just fine".
"We are all playing in the same sand pit so we've all got to be nice to each other I guess. Live and let live.
Thew said while council consulted widely before writing its reserve management plan, it could have done more to advertise its decision on mountain biking. He said no new tracks will be built and council will go back to consulting with the public about the plan in the middle of next year.
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