Replacing a snapped seat post bolt
10-31-22, 03:53 AM
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Replacing a snapped seat post bolt
The seat post bolt has snapped while I was riding. I've not replaced one before. Its length from thread end to the base of the top is about 45mm, its diameter is about 6mm. Looking on ebay for replacements, they seem to be shorter and thinner. Does that matter a lot when it is tightly fastened? I would attach photos, but I haven't posted enough messages yet.
10-31-22, 05:11 AM
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10-31-22, 07:27 AM
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The tough part is getting a replacement the right length.
In the meantime, if you're fortunate enough to have a real hardware store in your town (the last one here closed earlier this month after the owner's death), stop in with your bike. Find the fattest bolt that'll fit and is long enough, and get a nut and a couple washers that'll fit. Now you can ride until the new Official Seatpost Bolt arrives, and you can measure how long that seatpost bolt needs to be.
You can also check your LBS, and probably get help finding the right size, but the shops I've been to have limited bolts in stock (and none of them had the right size).
In the meantime, if you're fortunate enough to have a real hardware store in your town (the last one here closed earlier this month after the owner's death), stop in with your bike. Find the fattest bolt that'll fit and is long enough, and get a nut and a couple washers that'll fit. Now you can ride until the new Official Seatpost Bolt arrives, and you can measure how long that seatpost bolt needs to be.
You can also check your LBS, and probably get help finding the right size, but the shops I've been to have limited bolts in stock (and none of them had the right size).
10-31-22, 09:09 AM
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Once the bolt is replaced take care as to how much you tighten it as well as not allowing it to loosen. Most post bolts break from becoming loose enough to allow the seat to move about within the clamp. This looseness results in two problems for the bolt. One is that the clamp's serrations can be worn down and with the clamp not keeping in place (angle of seat is shifting) people will overtighten the bolt and snap it off. The other is that if the clamp is loose enough to flop back and forth the bolt will be bent this and that way. In tine it breaks much like a paperclip does when bent too far and too often.
Just like Al cotterless crank arms post clamp bolts really like being tight all the time and if let to loosen will result in non repairable damage. Andy
Just like Al cotterless crank arms post clamp bolts really like being tight all the time and if let to loosen will result in non repairable damage. Andy
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