seatpost malfunction

information on the brand, model & age would be helpful!

Mark Heiple said:

I was out riding today, and the seatpost clamp bolt (where the clamp
attaches to the saddle rails) broke.

I was standing to climb a hill, and when I sat down I heard a loud
'ping', followed by the sounds of something metallic bouncing on the
road. The saddle got all loose and wobbly, so I stopped. I found the
top half of the clamp with the end of the bolt still in it, but the
bottom half was gone. The only thing holding the saddle on was my
saddle bag, which snaps onto the rails and has a velcro strap that wraps
around the seatpost.

Fortunately, no crash or injury resulted, but it did put an end to my
ride.

I stopped at the bike shop to get a new seatpost, and showed them my
broken one. They said that it was kind rare to see the bolt break like
that, but it does happen.

Anything I can do to avoid a repeat, or to watch for so I'm not
surprised on the road again?

Thanks.

Mark Heiple <[email hidden]> wrote in news:mark-02AF05.20461223052004
@cinbell.usenetserver.com:

Quoted message said:

I stopped at the bike shop to get a new seatpost, and showed them my
broken one. They said that it was kind rare to see the bolt break like
that, but it does happen.

A broken bolt is not that rare. 99% of the time, it happens when someone
tightened the bolt way too much. Not applying grease or anti-seize to the bolt
makes the problem worse.

In article <[email hidden]>,

jim beam said:

information on the brand, model & age would be helpful!

Mark Heiple said:

I was out riding today, and the seatpost clamp bolt (where the clamp
attaches to the saddle rails) broke.

I was standing to climb a hill, and when I sat down I heard a loud
'ping', followed by the sounds of something metallic bouncing on the
road. The saddle got all loose and wobbly, so I stopped. I found the
top half of the clamp with the end of the bolt still in it, but the
bottom half was gone. The only thing holding the saddle on was my
saddle bag, which snaps onto the rails and has a velcro strap that wraps
around the seatpost.

Fortunately, no crash or injury resulted, but it did put an end to my
ride.

I stopped at the bike shop to get a new seatpost, and showed them my
broken one. They said that it was kind rare to see the bolt break like
that, but it does happen.

Anything I can do to avoid a repeat, or to watch for so I'm not
surprised on the road again?

Thanks.

I bought it about a 1 or 1.5 years ago from performancebike.com. They
listed it as Ultegra, but it is marked Shimano 600. The bike shop told
me that Shimano hasn't made that seatpost for probably 10 years. It is
really short and heavy.

In news:[email hidden],
Mark Heiple <[email hidden]> typed:

Quoted message said:

Anything I can do to avoid a repeat, or to watch for so I'm not
surprised on the road again?

Replace it with a Thomson seatpost. Well made, micro-adjustable and tough
as hell. I run them on downhill mountain bikes.

http://www.lhthomson.com

Mike

I've had two bolts break on two separate Weyless carbon seatposts. I'm
guessing, but both broke around 3000 miles of use. It's a hollow bolt, a
totally stupid design. Since I can't ride without a saddle (try it
sometime, if you think you can), I won't use it anymore. By luck, I had
some rubber covers for my look cleats, so the 5 mile walk didn't destroy my
cleats.

Did use grease, didn't overtighten.

mark-<< They said that it was kind rare to see the bolt break like
that, but it does happen.

Anything I can do to avoid a repeat, or to watch for so I'm not
surprised on the road again? >><BR><BR>

grease onto thw threads of all the bolts, grease onto the seatpost where the
rails live, don't make it too tight.

Peter Chisholm
Vecchio's Bicicletteria
1833 Pearl St.
Boulder, CO, 80302
(303)440-3535
http://www.vecchios.com
"Ruote convenzionali costruite eccezionalmente bene"

In article <[email hidden]>, Ken <[email hidden]>

Quoted message said:

Mark Heiple <[email hidden]> wrote in news:mark-02AF05.20461223052004
@cinbell.usenetserver.com:

Quoted message said:

I stopped at the bike shop to get a new seatpost, and showed them my
broken one. They said that it was kind rare to see the bolt break like
that, but it does happen.

A broken bolt is not that rare. 99% of the time, it happens when someone
tightened the bolt way too much. Not applying grease or anti-seize to the
bolt
makes the problem worse.

I suppose I could have over-tightened the bolt. I was having problems
with the saddle tilt slipping, and I had to tighten the bolt a lot to
stop the slipping.

The bike shop recommended a Salsa Shaft, which has a set of micro adjust
bolts that works independent of the clamp. I shouldn't have to tighten
this one down like the old post.

Mark Heiple said:

I stopped at the bike shop to get a new seatpost, and showed them my
broken one. They said that it was kind rare to see the bolt break like
that, but it does happen.

Nonsense. It is fairly common. This was, undoubtedly, a single-bolt
seatpost. Often, adjustment (to set the angle of the saddle) will result
in the bolt tightening against an angled piece, rather than exactly
perpendicular to the bolt. This stresses the bolt at the head and/or the
nut, and leads to the bolt snapping in the middle of a ride.

Quoted message said:

Anything I can do to avoid a repeat, or to watch for so I'm not
surprised on the road again?

Get a seatpost that uses two bolts to secure the saddle, not one.

--

David L. Johnson

__o | The trouble with the rat race is that even if you win you're
_`\(,_ | still a rat. --Lilly Tomlin
(_)/ (_) |

Mark Heiple <[email hidden]> wrote in message news:<[email hidden]>...
<snip>

Quoted message said:

I bought it about a 1 or 1.5 years ago from performancebike.com. They
listed it as Ultegra, but it is marked Shimano 600. The bike shop told
me that Shimano hasn't made that seatpost for probably 10 years. It is
really short and heavy.

Shimano 600 is the same as Shimano Ultegra. For a time, some packages
said "600 Ultegra" on them.

The Salsa Shaft is an adequate replacement.

Jeff

Callistus Valerius said:

I've had two bolts break on two separate Weyless carbon seatposts. I'm
guessing, but both broke around 3000 miles of use. It's a hollow bolt, a
totally stupid design. Since I can't ride without a saddle (try it
sometime, if you think you can), I won't use it anymore. By luck, I had
some rubber covers for my look cleats, so the 5 mile walk didn't destroy my
cleats.

I've broken no less than two seatposts, and I can attest to being
able to ride a few miles with no saddle. I rode a few rather
technical off-road miles (luckily, not a lot of hills anyway) with
the saddle strapped to my backpack when the first one broke.
--
Rick Onanian