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breaking seat post binder bolts(13 posts)

breaking seat post binder boltsbianchi boy
May 23, 2002 7:17 PM
Being a dufous, I overtightened my seatpost binder bolt and broke it today -- the second time I've done that in the past few months. I was 10 miles from home and had to call my wife to come pick me up because I wasn't gonna ride that far standing.

In both cases, they were Campy titanium bolts. Are ti bolts more prone to break than steel? Short of buying a torque wrench, is there a surefire method for tightening these bolts the proper amount? My mistake today was trying to make a saddle height adjustment during the course of a ride. However, I was careful to note how far I loosened the bolt, and then retightened the bolt with the allen wrench by the same amount. The bolt popped before I even had it tightened down as much as it was before. I think my replacement bolt will be steel this time.
i broke 3 of those...colker
May 23, 2002 8:06 PM
they are pretty. now, i use a cheap, ugly but strong steel stem bolt in the lug..
Question that has to be askedB2
May 24, 2002 5:17 AM
Probably not the problem, but is your seat post the right diameter?

Had a friend with a 26.8?? in a 27.2 seat tube. The problem was that the "clamp" that the binder bolts goes into had to clamp down so far that the holes for the bolt no longer aligned and bolt would bend. Can't do this too many times before it breaks.

Bryan
Question that has to be askedtarwheel
May 24, 2002 5:40 AM
Nope, everything is OK in that regard. My bike has a standard 27.2 post and 1" steel tubing. I actually broke the bolts on 2 different steel frames. It's my own fault, but I wouldn't think you would need a torque wrench to adjust a seat post. Never had this problem with a steel bolt breaking.
Liberal grease?TJeanloz
May 24, 2002 5:51 AM
The bolt should have a liberal amount of grease on the threads, that will let you get it tighter with less torque (if that makes any sense), and reduce the chance of breakage.
I'll remember that next time ...tarwheel
May 24, 2002 6:16 AM
I bought the bike new a year ago and haven't added any grease to the binder bolt, so it had whatever Excelsports put on it when they built it. That could have been an issue, though. The bolt that broke didn't seem totally dry but it wasn't covered in grease either.
correction ...tarwheel
May 24, 2002 9:29 AM
Now I feel doubly stupid. My Campy seat bolt wasn't ti, but steel. I felt a little better after talking to the bike shop owner about it, though, because he said they break seat bolts all the time. I bought 2 bolts, one for a spare. And I will grease this bolt nice and good.
I had the same problem12x23
May 24, 2002 9:53 AM
and switched to a SRP ti seatpost binder bolt. Problem solved.
I had the same problemlitespeedcat
May 25, 2002 5:49 PM
Where do I get my hands on an SRP Ti botl?

Thanks
Common problemNessism
May 24, 2002 11:21 AM
Keep a spare in your road kit. Also make sure you are using the proper length bolt. It may be that the male/female portions are bottoming out before the proper tension is reached to clamp the seatpost properly. Lastly, make sure you are greasing the bolt but not greasing the seatpost too much. It's hard to get the clamp tight enough if too much grease is used on the seat post.

Good luck.

Ed
Common problemcurlybike
May 24, 2002 11:26 AM
Once the post is greased, how much is too much? Seems that all excess will be scraped off upon insertion. How about, don't use anti-seize on the searpost, cause it iz too slippery.
well, it turns out ...bianchi boy
May 24, 2002 7:03 PM
It looks like I've been breaking bolts because the Campy bolts are little on the long side for my frames. I picked up 2 new ones today and when I installed one on my Gios it was hard to tighten it enough. The bike shop owner told me to add another washer if that happened, and it clamped down fine. This explains another mystery -- why the "female" end of the bolt looked uneven. Apparently the place where I bought the bike (Excel) had ground down the end of that piece to make the bolt fit better. It seems like it would have been easier to use a washer, or a bolt that fits better.
re: breaking seat post binder boltsComet26
May 28, 2002 10:06 AM
Had this problem for the first time in 20 years when I got my Bianchi...problem was in the frame...In order to get the bolt tight enough to "hold" the seatpost I had to "overtighten" the binder bolt...BAM> My solution was to get the Campy bolt and file off a strong 1/16 or more from the bolt so it wouldn't bottom out on the oppisite side before being tight enough.......problem was solved. Hope this helps!

PT