high_tea wrote: Coot-tha isn't that long or steep.
+1, the goat track from Mt Tamborine down to Canungra, now that's a scary descent, and that is one where i would be worried, but Coot-tha is no worry at all. I've only ridden it during the Coot-tha challenge rides, the first time it was dry and i didn't know the limit was 50 so i hit about 87 down past the botanic gardens, the second time it was wet and i kept it to 40-50 all the way.
I ride old steel bikes with single pivot or centrepull brakes a lot and never have an issue keeping things under control with those. If you are concerned about your tyres blowing out from heat, pull over and stop to let them cool down for a bit. Doesn't take as long as crashing, going to hospital and sitting at home recovering for days or weeks.