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I saw a new "mechanical" that I'd never seen before on today's group ride.

One of our riders had the bolt that clamps the saddle to the seat post, shear off. We were just ambling along on average pavement, no severe bumps or anything of that sort. He was a little back in the pack, and I did not witness the event. He was fine, no injuries. Fortunately, we were riding through a little village near a local lake, and he was able to get a ride back to the vehicles.

The group stopped, and we found the pieces, but the failure was such that we could not repair it.
 

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It shouldn't be a big issue, happened to me once. We were 40 miles from the hotel & I luckily found a ride back. My buddy wanted me to keep going, but no thanks!
 

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what? no badass 'finished the ride sans saddle' like the old days (a la Cindy Whitehead .. and the subsequent no-saddle races)?

I began the 50 mile race fast and hard. It was a drought year and there was lots of sand. The first sandy wash, which was about 1 mile into the 50 mile race, was too difficult for me to cross and ride out of, so I dismounted my bike and ran with it to the top of the hill. It was there, that I ran along my bike and jumped onto it, cyclocross style, only the binding bolt broke and my seat came off. After watching many riders pass me by, as I stood there sad and stunned, I decided to go for a training ride without my seat. BTW, since I never moved my seat post up or down, it was stuck inside the seat tube, so I just rode with it that way.
The initial motive to continue the ride was to burn off some of the extra fuel I stored up from carbo loading the night before. When I reached my adapted goal to just ride the short race loop, I had the top female rider, Jacquie Phelan, in my sights. Instead of quitting, I chased her down, and passed her. Then she commented, ” I knew you wouldn’t quit.” , and she passed me again. We traded the lead several times, before I finally broke away from her fairly close to the summit. From there to the finish I out rode her and was never beaten by her again, except when I’d ridden the wrong course, made some other navigational mistake, or had a mechanical.
Cindy Whitehead-Buccowich | The Marin Museum of Bicycling and Mountain Bike Hall of Fame
 

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The same thing happened to a fellow rider & there did not appear to be anything like a a pot hole or bump for a cause.
 

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I saw a new "mechanical" that I'd never seen before on today's group ride.

One of our riders had the bolt that clamps the saddle to the seat post, shear off. We were just ambling along on average pavement, no severe bumps or anything of that sort. He was a little back in the pack, and I did not witness the event. He was fine, no injuries. Fortunately, we were riding through a little village near a local lake, and he was able to get a ride back to the vehicles.

The group stopped, and we found the pieces, but the failure was such that we could not repair it.
This kind of failure is often a long time coming. Metal defect or thread cut too sharply (stress riser) and the fatigue finally gets it. Not often the result of a single impact.
 

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This kind of failure is often a long time coming. Metal defect or thread cut too sharply (stress riser) and the fatigue finally gets it. Not often the result of a single impact.
Yep. A cheap Shimano saddle clamp bolt broke on me for exactly that reason. The bolt sheared off between two threads that had been repeatedly stressed out riding. It was a cheap alloy bolt.

The nice thing about two bolt saddle clamps is they never break. Highly recommended for clydesdales.
 

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That happened to me. I fell right off the back of the bike, sustained minor road rash and bruises. Fortunately I was at the back of the line at the time. I attribute the failure to the removal of the seat post a few weeks prior. It was stuck and I had to lever on it a bit using the saddle to get it to move. CF post in steel. I rode home standing, 5 miles. I have also seen this happen to another friend, on a climb.

I am currently using a post with a double bolt set up.
 

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TI fell right off the back of the bike
When this happens, don't let go of the handlebars if you want to stay on the bike. As far as bike control was concerned, it was no big deal, but that is me.
The one that broke on me was the 2 bolt type.
 

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When this happens, don't let go of the handlebars if you want to stay on the bike. As far as bike control was concerned, it was no big deal, but that is me.
The one that broke on me was the 2 bolt type.
I knew someone was going to come back and say that! :lol: Those two bolt ones have smaller bolts and can be adjusted too tight very easily when trying to make the saddle level.
 

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Those two bolt ones have smaller bolts and can be adjusted too tight very easily when trying to make the saddle level.
Use a torque wrench. :idea:
 

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This has happened to me twice on the mountain bike. One time when I was only 5 minutes into a race (ended my race). Another time was when I was riding alone on a remote trail and was about 8 miles from the trailhead (wasn't able to repair and rode the rest of the way without a seat!).

This was a seatpost with 2 bolts, one fore and one aft. It was probably just due to fatigue over time, and it just decided to give way. Never understood why such a small 5mm bolt is used for these seatposts. The seatposts with a single bolt usually have a bigger diameter bolt and are less likely to fail IMO.
 

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Use a torque wrench. :idea:
Riders don't know how to level those two bolt saddles. They don't realize that for every turn on one bolt, there has to be an opposite turn on the other bolt to get the saddle to level. I frequently found saddles not leveled and one bolt really tight, to the point I had to loosen the other bolt quite a bit to get the first bolt to loosen up.

A bit more complicated than simple torquing. I have a really good torque wrench, my hand. But I'm working with alloy and steel, not this wimpy plastic or cheap aluminum. :frown2:
 

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This has happened to me twice on the mountain bike. One time when I was only 5 minutes into a race (ended my race). Another time was when I was riding alone on a remote trail and was about 8 miles from the trailhead (wasn't able to repair and rode the rest of the way without a seat!).

This was a seatpost with 2 bolts, one fore and one aft. It was probably just due to fatigue over time, and it just decided to give way. Never understood why such a small 5mm bolt is used for these seatposts. The seatposts with a single bolt usually have a bigger diameter bolt and are less likely to fail IMO.
Surprised to hear, but not very surprised. Cheap cast alloy bolts are easy to break. I've only seen single bolts breaking, and surmised that two bolt schemes addressed that problem. Guess not.
 

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Happened to me once, commuting on a fixed-gear bike. I felt/heard the movement, and stood up before the saddle completely separated from the bike, thus could stop safely. I removed the seat post and completed the ride standing, but doing a long stretch standing with a fixed-gear was an interesting challenge. Climbing that way is natural, but getting up to speed on the flats and then having to stay standing without the ability to coast was pretty weird.
 

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I have a really good torque wrench, my hand.

While I'm fairly competent mechanically, one thing I have a hard time with is tactile memory. I have sheared enough bolts to have the wisdom to use a torque wrench when at all possible.
 

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Climbing that way is natural, but getting up to speed on the flats and then having to stay standing without the ability to coast was pretty weird.

"Weird"?? Not "exhausting," not "terrifying," not "not worth it"?? :p

This is why I carry my train/MetroCard. :D
 

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"Weird"?? Not "exhausting," not "terrifying," not "not worth it"?? :p
Mostly weird. Somewhat tiring (NTTAWWT). Slightly scary (but that goes with fixie riding, if you push yourself). Not not worth it.

This is why I carry my train/MetroCard. :D
A reasonable option, when you live in a big city with great transit. Here in beautiful Hartford, a bus might come along in an hour. And in truth, I finished the ride to work (I was only a couple miles away), and took the bus home, and brought in the repair parts the next day.

But it was sort of fun, in a weird way.
 

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While I'm fairly competent mechanically, one thing I have a hard time with is tactile memory. I have sheared enough bolts to have the wisdom to use a torque wrench when at all possible.
I see your point. Me too! So I go by feel. With Campy alloy stuff, you can feel the bolt tighten quickly when snugged up. With cheap aluminum and carbon, bolts don't tighten positively like that. You have to "torque them down" trying to figure out at what point the threads will start stripping away. You know what I mean? For those, definitely use a torque wrench. Or seat clamp bolts, mine anyway. I have to torque it to 10 ft.pounds or the saddle won't stay level. :confused: That's a bit tighter than a little allen wrench will do it.

Yeah, torque wrenches for sure on carbon stuff. :shocked:
 

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I see your point. Me too! So I go by feel. With Campy alloy stuff, you can feel the bolt tighten quickly when snugged up. With cheap aluminum and carbon, bolts don't tighten positively like that. You have to "torque them down" trying to figure out at what point the threads will start stripping away. You know what I mean? For those, definitely use a torque wrench. Or seat clamp bolts, mine anyway. I have to torque it to 10 ft.pounds or the saddle won't stay level. :confused: That's a bit tighter than a little allen wrench will do it.

Yeah, torque wrenches for sure on carbon stuff. :shocked:
Fredrico,
I was using a Campy Daytona seatpost of one of my bikes. I always use a torque wrench. One of the seatpost clamp "nubs" snapped off during a ride. This was really surprising to me since this seatpost is no lightweight
 

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Fredrico,
I was using a Campy Daytona seatpost of one of my bikes. I always use a torque wrench. One of the seatpost clamp "nubs" snapped off during a ride. This was really surprising to me since this seatpost is no lightweight
All I can say is, the old Campy Super Record was overbuilt. The chrome steel saddle clamp bolts they put on their seat posts were ver high quality, as were their BB bearings. I'll beat that stuff to the grave!

What did you torque it down to? Did the break occur on the torqued piece? :nono: Around the early 90s, Campy had a period when they too had quality issues. I guess you got hit. Those nubs were cast aluminum right? The older ones were "cold forged," much stronger. Their cranks broke, too, shockingly. The two I'm running are still good after 70K miles on each. I do keep a close eye on 'em though when I lube the chain.
 
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