Recent content by carlfogel

Virtually all stainless steel bicycle spokes are supposed to be 304 or 18/8, according to the manufacturers. I ended up heating spokes to a cheery orange glow, but that was just being thorough--the bending motion is noticeable almost as soon as the flame from a propane torch hits the surface...

It's the stainless spoke that unbends (straightens). The carbon spoke bends even further. It isn't a question of which spoke bends more when heated, but rather why the two spokes bend in opposite directions. Bent at the same 90 degree angle _|, the carbon and the stainless spokes bend in...

Cheap (or very old) bicycle spokes are made of carbon steel. Most modern high-quality spokes are made of stainless steel. When bent at roughly 90 degrees and heated with a propane torch, a carbon spoke bends further, curling up slightly, but a stainless steel spoke unbends, uncurling...

Here's a link to the data from a nice experiment from a data acquistion company that demonstrated the Mpemba effect: http://www.picotech.com/experiments/mpemba_effect/results.html The hot 42C water froze much faster than the colder 18C water sample.

When two pads squeeze a moving rotor with thousands of pounds of force in a disk brake, the friction resists the rotation of the disk enough to slow a car. How much resistance (if any) does the squeezing of the pads provide if you try to pull the moving rotor out at roughly 90 degrees...

Dear Steven, As Stingray suggests, a lighter flywheel may be worth looking into. Years ago, some short track motorcycles reduced the rotating mass of their flywheels for greater acceleration by removing the flywheel's electrical guts. Instead of generating its own electricity from the...

Dear Chi, Regrettably, mechanic sites like Barnett and Park Tool and spoke companies like Sapim and Swiss DT prefer to say nothing about spoke-squeezing, pro, con, or explanatory, even when asked. They do address the visible and audible mechanical unwinding of spoke twist, but not the...

Dear Chi, Sorry, but I'm afraid that it's easy to mis-read my long-winded posts. Using a smooth screwdriver shaft to twist the spokes tighter where they cross is another common method of stress relief (both methods increase spoke tension). It also can bend the spokes into slightly better...

Chi Meson wrote:There is much evidence that the "Parallel spoke squeeze" is the wrong way to "detwist " the spokes. The additional force is indeed as calculated by Krab, and with todays doub;e-butted spokes, it is not a good idea since elongation can occur. There are other methods for detwisting...

Krab wrote: A 100 lb. sideways force is 50 lb. at each end. But the ratio of side force to total force is sin(4 to 5 degrees). This means the total force is 50lb/sin(4 to 5 deg.)= 570 to 720 lbs. So the additional is 370 to 520 lbs. Dear Krab, Thanks--I take it that you'd apply the classic...

Gokul43201 wrote: When you squeeze the spokes together, do they get permanently deformed or are you within the elastic limit ? Purely from the info you have given, and assuming 4-5 deg is correct, there is a rough calculation that can be done. Assuming 295 mm is the length under strain...

Hello, Typical bicycle wheels have 36 spokes that are trued to a final tension of roughly 200 pounds. If a pair of adjacent spokes are squeezed together with one hand with a force of roughly 100 pounds, what does the spoke tension rise to? I'm asking because this healthy-squeeze...