M5 Bike Seat Bracket Sheared Off

M5 Ti ShockProof Bike Troubles

This one is a head scratcher.  I was riding the other day and felt the seat just drop.  Fortunately no accident.  I stopped and lifted up the seat cushion thinking maybe I just needed to tighten the screws (A recurring problem due to location and vibration).  Unfortunately I was not so lucky.  The mounting bracket for the seat had completely sheared off.

This bicycle has a total of just over 3,000 miles on it... but it is 10+ years old now.  I've replaced many components over that time period for both comfort and usability.  The wheels and brakes it came with were not very good.  So I expect to do maintenance and upgrades... which I do.  I figure I'm very near $6,000 invested in this bicycle now.  I sure didn't expect any of the frame components to fail.  And there are no other cracks on the frame anywhere.  One of the things that impressed me about this Bicycle when I first got it was how clean the welds were... and still are.

What's interesting here is the M5 Weld didn't fail... the metal itself just sheared off.  I suspect there are several reasons for this.

  1.  The metal is pretty thin overall and mounted at a slight angle to the frame so when the seat comes down on it the transfer of forces goes through the metal at a slight angle instead of vertical.
  2.  Holes are drilled into the metal to allow cables to pass.  I always hated this as it also has worn the cable covering off.  It just seems like "After thought" Engineers.  There seems to be a lot of "Just use a Zip Tie" Engineering in the recumbent World.
  3. There is nothing to absorb the shock on the metal when you hit a pothole or object and your weight bounces up and then back down.  And for the record I'm less than 200lbs.

Anyways enjoy the Photos of my freshly disabled M5 Ti Shockproof below.  It is what it is... nothing lasts forever.  And while I want to get a Trike... they are just too dangerous on the city streets where I usually end up having to ride until I can get access to paths.  I'm scared to be too low to the ground... just last year a recumbent cyclist in the area I was riding was killed when a Truck turned a corner and ran right over him.  The driver said he didn't even see him.  I believe he was on a small wheeled Sun or Clone of some type.

Once again looking hard at Azub... would probably already own one if I could get myself in a shop where I could actually see one.  Not really excited sending off a pile of money and then hoping everything just works out.

Another Angle of Broken Brackets

Another Angle of Broken Brackets

Broken Bracket Again

Broken Bracket Again

broken seat bracket 1

Sheared off Seat Bracket

Broken off Edge Remains on Tube

Broken off Edge Remains on Tube

You can see here where the holes were drilled

You can see here where the holes were drilled

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