Trapped 55kph on a flat section of a race a few weeks ago, about 65kph on a downhill section when I was out riding with some friends earlier this season. On my road bike I've hit almost 85kph though, that shit is scary haha.
62kmh down some not so steep cattle trail, all very skinny single track with lots of quartz and jasper rock jutting up out of hard pack clay, it has about 12 different single track line options made by a bunch of cattle that walk up and down the ridge line everyday had to bunny hop a 3'+ rock that surprised me on the trail, and pinched my front tyre, that was a hell of a rush, landing a flat front wheel at >50kmh and keeping it up
46km / hour down a fairly steep hill on my older terrible cheap bike. On my newer bike, probably faster. Our hills aren't long enough or steep enough to really build up more speed than that.
At least the hills I've found
Also, I'm running dirt tires. I'm sure if you had slicks on you could pick-up more speed.
41mph/65.98kph on my dj/4x bike!! Wont be doing it again tho the bike started shaking at like 39mph but I guess thats the quality of north yorkshires roads!!
Down a road hill in Brimscombe, Gloucestershire, UK
No helmet and V brakes when I was about 18ish 10 years ago.
Living the dream.
Know that hill well buddy, and it's a loooong haul up again
Brimscombe Hill? That's well good. A friends parents have a holiday home at the bottom, across the main road and up the road the other side. We used to go there loads when we were younger. I live in North Wales but know that area a bit. Stroud, Cirencester and Brimscombe. Noah's Arc bike shop. Messing about by the canal. Scrap yard by the rail way line. Football on Brimscombe pitch.
32mph on the gps on my phone. About 20 feet later I wasn't moving... Apparently if you hit that corner fast enough you lose enough grip coming over the crest that you can't make the corner.