Manuals and Guides(why should you read them)Why not?

[SHOOP]

do you even read them to know how to use or care for your bike
I let my friend ride my mtb then he started doing bmx stunts wheelies or stunts that could wears the bikes chassis strenth and loosen parts,So when i went on the bike it felt weak the pedels were making clink sounds its can't shift to 8 gear

[michaelnel]

The manuals that come with bicycles are pretty elementary. I have not ever found anything in them that I didn't already know.

The problems your friend's bike has wouldn't be covered in the manual for the bike. Most of them devote much of the content to stuff that pleases their lawyers, like how to use the quick releases.

[mac]

do you even read them to know how to use or care for your bike
I read the manual on how to adjust my Shimano front and rear derailer by turning the top & bottom screws clockwise/counterclockwise and tightening the cables.

[Michel Gagnon]

Last time I bought a production bike, here is what I found in the manual.

1. Wear your helmet at all times.
2. Reflectors have been installed for your safety. Keep them there!
3. Don't ride at night! or is it Riding at night is dangerous! Then they say "if you must do it, wear bright clothing".
4. How to press hard the quick releases
5. Have your bike checked and maintained by the bike shop regularly
6. Check all bolts before each ride!

Now, if you want my humble opinion on these topics and on what should be in an instruction manual:

Point 1. Good practice, I think, but not related to the bicycle.
Point 2. Reflectors may be useful if they are clean and well aligned. No word on these two factors.
Point 3. Bull****. Get lights. A good instruction manual should actually guide the owner (who may be new to cycling) onto the various types of lights available (no brandnames, but generic on batteries, generators, LEDs, halogen, HID...). It should also stress that lights are important.
Point 4. The item has some importance. Except buried as it is amongst so much useless or ridiculous information, the cyclist tends to consider that information in a similar fashion.
Point 5. But how about talking about basic maintenance? It is as if GM or DaimlerChrysler asked their customer to go back to their dealers every week to check oil and tire pressure.
Point 6. Again, some common sense please !

And to conclude the instruction manual, why not introduce extras that would make the ride more enjoyable: fenders, racks, aerobars... (depending on the bike)

[Raiyn]

The component manuals are always more useful than the general rag the bike companies kick out