Selecting An Appropriate Bolt

On 4/14/2017 12:33 PM, jbeattie wrote:
On Friday, April 14, 2017 at 7:27:06 AM UTC-7, AMuzi wrote:
On 4/14/2017 9:14 AM, Art Shapiro wrote:
On 4/14/2017 5:35 AM, AMuzi wrote:

Original handlebar clamp bolts are Grade 8; readily
available and cheap.
Grade 5 may be strong enough but for pennies difference I
suggest an 8.

How does one get these "readily available" Grade 8 guys?
Deda doesn't seem to have much of a web presence outside of
Italy. Is this a generic item stocked by a good LBS?


Any metric fastener supplier if not your local hardware store.

https://duckduckgo.com/?q=DIN+912+grade+8&t=ha&ia=web

My neighborhood hardware store has them: http://aboysupply.com/wp-content/upl...1024x415_c.png They have a crazy selection of fasteners.

By the way, what's the deal with thread pitch? I always worry I'm getting the wrong pitch, but I guess that the whole "standard/fine/extra fine" thread pitch only kicks in with fasteners over 8mm(?). Otherwise, it's a pre-set. Right?

There are metric fine pitch threads
https://mdmetric.com/tech/thddat3.htm
like 5mm-0.5 instead of 5mm-0.8 but I've hardly ever come across them
in real life.

Fine thread fasteners are a bit stronger and more resistant to vibrating
loose. But in most cases, you can solve both problems by other means -
perhaps "next size up" and Loctite.

--
- Frank Krygowski