- News
- Reviews
- Bikes
- Accessories
- Accessories - misc
- Computer mounts
- Bags
- Bar ends
- Bike bags & cases
- Bottle cages
- Bottles
- Cameras
- Car racks
- Child seats
- Computers
- Glasses
- GPS units
- Helmets
- Lights - front
- Lights - rear
- Lights - sets
- Locks
- Mirrors
- Mudguards
- Racks
- Pumps & CO2 inflators
- Puncture kits
- Reflectives
- Smart watches
- Stands and racks
- Trailers
- Clothing
- Components
- Bar tape & grips
- Bottom brackets
- Brake & gear cables
- Brake & STI levers
- Brake pads & spares
- Brakes
- Cassettes & freewheels
- Chains
- Chainsets & chainrings
- Derailleurs - front
- Derailleurs - rear
- Forks
- Gear levers & shifters
- Groupsets
- Handlebars & extensions
- Headsets
- Hubs
- Inner tubes
- Pedals
- Quick releases & skewers
- Saddles
- Seatposts
- Stems
- Wheels
- Tyres
- Health, fitness and nutrition
- Tools and workshop
- Miscellaneous
- Buyers Guides
- Features
- Forum
- Recommends
- Podcast
forum
Selle Italia advert
The advert at the top of road.cc says the new Flite friction free saves 0.7w per pedal stroke (which doesn't make any sense, because wattage is power/time, but is that another matter?), gaining an increased 3% in speed... 3% of 23 is 0.7. Are they saying they have gauged this on someone producing 23 watts. Actually, let's triple to 2.1 watts. That for someone pedaling at 90rpm (three strokes per second). Are they saying the average cyclist produces 69 watts? Also, to increase the speed by 3% at 20mph, due to the air resistance being the square of velocity, would probably be much more than a 3% increase in power. Let's say 6% because I can't be bothered working it out. Which makes our hypothetical cyclist's output 35 watts or so.
Can someone from Selle Italia explain the maths in the advert to me?
If you're new please join in and if you have questions pop them below and the forum regulars will answer as best we can.
Latest Forum Topics
Latest Comments
- ktache 3 hours 28 min ago
The small frame, the aggressive posture, lots of standover height.
- mctrials23 4 hours 24 min ago
As i've said before, the police should be sued for a lot of money when someone they have knowingly ignored has gone on to commit a serious crime....
- David9694 4 hours 31 min ago
'Bad parking' blocks firefighters multiple times on same emergency call-out...
- David9694 4 hours 35 min ago
Cambridgeshire boy, 13, crashes Audi into garden wall after taking it from home...
- Adam Sutton 5 hours 21 min ago
Good stuff. Now do it on cycleway C9 through Hammersmith to Chiswick.
- mark1a 5 hours 30 min ago
It's technically allowed but it's not known as "London's Orbital Car Park" for nothing.
- Dogless 6 hours 38 min ago
You're defending bombing hospitals and refugee camps and starving children.
- mattw 9 hours 18 min ago
Used car salesman is a complete attention-seeking plank....
- tubasti 9 hours 35 min ago
I don't know if they're any better, but they's certainly become more boring.
- FionaJJ 10 hours 1 min ago
At risk of being cynical, and stereotyping the police, it's so they don't have to leave the comfort of their panda cars and pursue on foot when...
Add new comment
3 comments
It's quite simple really, and explained fully here:
http://star.psy.ohio-state.edu/coglab/Miracle.html
Brilliant! Not at all what I'd expected from that link, but then I didn't pay attention to the file name. The artist must have re-copyrighted that cartoon, though. I've got it on a t-shirt which, I'm pained to admit, dates from long before 2006.
Yes, I think the cartoon goes back to the 40s or 50s. It looks like something from The New Yorker.