A recent experience where a logging truck had given her no room had left her feeling her life was at risk, she said.
"I thought 'this is it', it's over, basically. You know if one of them hits you, you're not going to walk out of hospital with a broken arm - it's going to be a lot more serious than that."
Recent resealing work done on that stretch of road was rough and did not reach the edge of the road where a lot of loose metal and broken glass had collected, meaning cyclists had to ride closer to the traffic, Miss McKenzie said.
"[The edge of the road] is very bad to ride on. You're asking for a puncture, if nothing else. Even if they rolled it right to edge of that barrier you could get further over. It wasn't great before, but, since they resealed it, it's a whole lot worse."
The placement of the barriers also made little sense, she said.
"Very little of these roadworks that get done improve things for cyclists. The seal seems to get rougher, presumably because it's cheaper, and I can understand barriers in areas where you've got a cliff down the bottom but, if you run off the road in a car heading down Cornwall Rd, you're going to end up in a paddock.
"I think having barriers there just makes it more dangerous; it doesn't make it safer."
She had written to the Masterton District Council, which directed her query to the New Zealand Transport Authority (NZTA) but so far had received no response.
"At the very least the seal needs to be rolled right to the barrier. Better yet there needs to be somewhere where the cyclists can preferably be on the other side of the barrier.
"We are supposed to be a cycle-friendly region, we are advertised as that all the time, so let's prove it."
A spokeswoman for NZTA confirmed reports had been received of excess loose chip since the road was resealed after Christmas. A contractor was to sweep the shoulder up to the barrier yesterday and would continue to monitor the seal.
The barriers had been designed to ensure a minimum shoulder width of 1.5-metres for cyclists, the spokeswoman said.
NZTA would be assessing the site as part of ongoing improvements for cyclists.