On 1/16/2020 10:31 AM, AMuzi wrote:
On 1/16/2020 8:54 AM, sms wrote:
On 1/16/2020 5:57 AM, AMuzi wrote:
On 1/16/2020 4:25 AM, Sir Ridesalot wrote:
I've advised people not to drill an alloy handlebar in
order to route their brake cablesÂÂ* and/or derailleur
cables inside the handlebar. I looked on the web for
images of broken alloy dropbars that have failed because
of being drilled but can't find any. I KNOW I had such
images on my other computer that dies. Can anyone here
give me links to such images of broken drilled alloy
dropbars?
Cheers
Broken handlebars are well documented:
http://pardo.net/bike/pic/fail-001/000.html
But although the principle of a hole in a dynamically
stressed tube is clear, I could not find an image. I have
seen home-drilled bars propagate cracks but not actually
fail. That may be a function of low mileage on specialty
bicycles.
Apparently it's not uncommon to drill holes in motorcycle
handlebars, and there's even a tool for that
https://www.kiwavmotors.com/en/tools-accessories/controls/kiwav-motorcycle-handlebar-drill-guide-detail.
Probably you wouldn't want to do this on an aluminum alloy
handlebar though. As you stated, the principle is clear.
People do dumb things all the time and get away with it, but
it still doesn't make doing these things a good idea.
As Jobst Brandt once said, "I don't know many riders who
believe that drilling a hole in a frame tube is a reasonable
concept." The same applies for drilling holes in handlebars.
Motorcyclists may but ought not. It's both stupid and illegal see
typical WI statute 347.486:
https://docs.legis.wisconsin.gov/sta...es/347/III/485
Are you referring to the prohibition against "improvised" handlebars?
I'm not sure that would specifically prohibit a hole.
I know one guy - a professional bike mechanic - who snapped the
handlebar on his 1980s aero bicycle (small front wheel, disc rear,
extremely low bars, etc.) He was sprinting away from a stop and the bar
snapped at the hole for the "aero" brake cable.
But I think the forces on motorcycle handlebars are much lower than
those on bicycles. It's not that I recommend drilling MC handlebars; but
I think the risk would of fracture would be far lower than for a bicycle.
Someone sells a tool for it.
https://www.amazon.com/KiWAV-Motorcy.../dp/B00EH2M40G
--
- Frank Krygowski