g-boaf wrote:
Sounds a bit dangerous. Velodrome seems a safer bet.
No it is not, the only velodrome in WA is closed, having it's track replaced.
If you want to 20 minutes on a climb at a consistent gradient, something like 7km at 5% (350 metres vertical gain), you are out of luck.
There is no climb in Perth or surroundings with 300 metres of vertical gain
The closest in 275m Albany Hwy over 10km from Armadale to Canning Dam Rd, never ridden it, but from Strava you see the gradient vary from 0 to 8%, averaging 2.75%.
If you only want a 8 minute climb, Pipehead Dam to Kingsbury has 2km at 8%, followed by 400 metres at 2% or so.
Flat, PSP south of Cockburn Central, 50km of relatively flat (worst is 300m at 3%) uninterrupted and very safe. I regularly commute on the 15km section from Kwinana to Cockburn Central, use it for threshold intervals on road and TT bikes, and lucky if I see more than one other person. Even today, at a most reasonable time it was more popular, total of 10 riders, a jogger and a walker (and that was there and back).
If you are near Champion Lakes, there is a 5km path around the lake. I have only ridden in time trials, but flat, smooth and relatively safe, if you get one kink wrong on a TT bike, you can end up in the lake.
ATTA have a 20km TT at Champion Lakes on 30th April
http://atta.asn.au/
Want to set your FTP racing for an hour, Peel Districts Cycling Club have a 40km TT on 30 April
http://pdcc.asn.au/events/time-keepers-tt-2017/