Crankworx Rotorua Downhill presented by iXS LIVE on Pinkbike

# phutphutend

Block user

## Recent

phutphutend mikelevy's article
Mar 26, 2015 at 12:25
8 hours
phutphutend mikelevy's article
Mar 25, 2015 at 15:04
1 days
Justin Leov's EWS Remedy 29er - Crankworx Rotorua
Agreed, I just have trouble with intuitive science. Just because it intuitively make sense, it does mean the science is correct. It looks like a Trek! But it's fast because it ridden by Leov. Like he says he feels comfortable on it and that is the most important thing. If you believe the contact patch is bigger and this gives you confidence to go faster. You may well go faster, even if in reality it makes bugger all difference. All good fun...
phutphutend mikelevy's article
Mar 25, 2015 at 14:22
1 days
Justin Leov's EWS Remedy 29er - Crankworx Rotorua
I'm right, most of you are wrong... Rider weight is reacted by tyre pressure x contact patch. Force = pressure x area. No where in that calculation is wheel diameter. Rewriting the equation gives Area = Force / Pressure. An 80kg rider plus bike = 800N (approximately), with tyres at 0.2MPa (29psi), needs a contact patch of 4000mm^2. Or 2000mm^2 per tyre. So 20mm x 100mm maybe for a 26" tyre. But perhaps slightly longer for a 29" tyre, say 17mm x 117mm. For a 100 mile tyre, say 0.1mm x 20,000mm But still the SAME area. If grip is dependent on contact patch shape is another thing? Tyre knobbles may also confuse things. Perhaps a longer patch is better for braking but less good for turning, that would make sense to me...
phutphutend mikelevy's article
Mar 25, 2015 at 5:38
2 days
Justin Leov's EWS Remedy 29er - Crankworx Rotorua
Can someone let Leov know that the tyre contact patch area is independent of tyre size. I think he's said this before in a previous article. Contact patch is proportional to rider weigh and tyre pressure only. It may well change shape, but it doesn't change size!
phutphutend devinci's article
Mar 23, 2015 at 12:34
Mar 23, 2015
Video: Adventure in the Azores with Oton and Galy
Fox really must have been having a bad day when they designed those kits. Muddy green and flourescent yellow!
phutphutend DoyenUK's photo
Mar 19, 2015 at 5:34
Mar 19, 2015
Looking good. What tubes do you use, still plain gauge?

Mar 3, 2015 at 4:41
Mar 3, 2015
Mar 2, 2015 at 2:17
Mar 2, 2015
Nice feature on dirt dude!!