Okayyyy - finding myself once again in that realm where it seems blokes are just BORN with knowledge... since I can't find an explanation for things anywhere... so...

Males of the species... please impart your knowledge:

BOLTS:
1. WHY are some bolts on a bike allen/socket heads and other hex - and yet others screw heads?

2. WHY can't I just change ALL the bolts to allen heads - that way, I only have to carry ONE ALLEN KEY in my toolbox?

3. WHY are there different thread sizes/pitches (M4 M5 M6 etc.) to fasten things - why not just use the same pitch?

4. DOES the size of the ALLEN HEAD change with the size of the pitch? Or WHY are there different sized ALLEN HEAD BOLTS - why not just have one size?

5. If A2 stainless steel has less tensile strength than 8.8 carbon steel bolts.. why am I changing all my bolts to stainless steel?

NUTS:

1. IF NYLOCK nuts are so wonderful - why not change ALL the nuts on the bike to NYLOCK?

2. WHY are some of the nuts on my KTM "flange" nuts? Is this to make the surface of the fastener bigger... for bigger holes?

WASHERS:

1. What is the real purpose of washers - WHY are they not used on EVERY bolt? Do they act as SPACERS? Or do they act as seals? Or WHAT?

2. If SPRING WASHERS are shake/vibrate proof - WHY not use them on all fasteners?

3. If SHAKEPROOF WASHERS (the ones with teeth) are shake/vibrate proof - WHY NOT USE them on all fasteners?

4. If WAVEY WASHERS are shake proof...

Which is REALLY shake proof: Spring, toothy or wavey??

JARGON:

What is the difference between:

Stainless Steel UNC Fasteners

and
Stainless Steel UNF Fasteners

and
Stainless Steel Metric Fasteners

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