Singlespeed & Fixed Gear - Oh **** seat tube bolt

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View Full Version : Oh **** seat tube bolt


bboysubhuman
07-12-07, 09:33 PM
****. I was just raising the seat a little and when I went to tighten the bolt(not even over-tightening it) the damn thing snapped in half. It wasn't even tight enough to hold the seat post in place. And here's the really bad news. It's one of those allen key bolts that screws directly into the frame(I guess it's better described as a screw--not a bolt). Someone, please tell me it's fixable. How can I get it out? :(


666pack
07-12-07, 09:38 PM
if it's the bolt itself that snapped you should just be able to get a replacement at your lbs.

bonechilling
07-12-07, 09:58 PM
You might have to drill out the part of the bolt without the allen head on it. If you know anyone with a drill-press, then they can do it in a matter of minutes. Your LBS might well have one.

A new bolt is readily available at any half-decent bike shop.


automatic_sheep
07-13-07, 02:43 AM
managed to do that twice in one day :( Annoying but not debillitating (except for self-esteem)

Retem
07-13-07, 03:08 AM
get a new seat post clamp use veneer calipers to measure the seat tube then order a bmx seat post clamp in the appropriate size you save some money and they come in fun colors

*new*guy
07-13-07, 04:18 AM
When you buy the new binder bolt, get two of them and carry one in your bag with you when you ride.

You should be able to drive the old one out w/ an awl or long phillips and a mallet.

Sammyboy
07-13-07, 06:15 AM
Critically, use vernier calipers. Veneer calipers are only suitable for measuring the depth of the very thin wood coating on furniture......

filtersweep
07-13-07, 06:19 AM
Why is it a screw? Somehow, I think it is still a bolt.


****. I was just raising the seat a little and when I went to tighten the bolt(not even over-tightening it) the damn thing snapped in half. It wasn't even tight enough to hold the seat post in place. And here's the really bad news. It's one of those allen key bolts that screws directly into the frame(I guess it's better described as a screw--not a bolt). Someone, please tell me it's fixable. How can I get it out? :(

genericbikedude
07-13-07, 06:24 AM
I've done this a few times. I'm told that these things are designed to break easily to avoid damaging the frame through overtightening.

Moose
07-13-07, 06:30 AM
His seat clamp is integrated with the frame, not a removable one some have suggested replacing. I also assume the broken bolt is still threaded into the frame, DO NOT try to drive it out! You'll need to use a screw extractor of some sort if it's to stuck to turn out by hand.

Devolution
07-13-07, 06:45 AM
Easy out and a new bolt. Don't just drill the bolt out, unless you're willing to retap at a larger size.

http://www.toolprice.com/category/screwextractors/

Don't just drill the bolt out, unless you're willing/able to retap at a larger size.

And what's with people breaking seatpost bolts? Ease up a bit, assuming you're seatpost is the right size you should have to torque them down that much.

Grasschopper
07-13-07, 07:45 AM
Lets slow down a little here...is this a bolt that threads into the frame or one like the Campy binder bolt (http://aebike.com/page.cfm?PageID=30&action=details&sku=ST9800)with 2 halves that fit on opposite sides of a part at the top of the seat tube?

My Merckx has the latter and those Campy bolts are notorious for snapping...I have killed 3 of them myself and I always use a torque wrench. I think they may actually be designed to snap after 2 uses or someone told me that once anyway.

http://aebike.com/images/library/catalogs/soc/prodl/ST9800.jpg

peabodypride
07-13-07, 08:35 AM
The classic McGuyver way to remove stuck bolts or stripped screws is to soldier a thin piece of metal (maybe a bent paperclip or, if that's not going to pull the bolt out, a small screwdriver) to the inside of the hex hole.

Boss Moniker
07-13-07, 08:57 AM
Your frame itself is threaded? I thought that was a big no-no.

Make sure you don't actually have a collar.. sometimes it's not so obvious.

Moose
07-13-07, 07:59 PM
Your frame itself is threaded? I thought that was a big no-no.
Not all that uncommon actually, I assume this because, out of the 9 bikes in my basement, three of them have this feature. But you know what happens when you assume... :D

Igneous Faction
07-13-07, 10:48 PM
Good lord, apparently no one reads posts anymore and just posts wild recommendations that, in actuality have nothing to do with the topic at hand.

So what you have is half a bolt threaded into your frame with no way to get it out? Bummer. Whoever suggest extractors is right on the money.

Moose
07-13-07, 10:51 PM
Yay, I win!

hiredgoons
07-13-07, 11:25 PM
Not all that uncommon actually, I assume this because, out of the 9 bikes in my basement, three of them have this feature. But you know what happens when you assume... :D

Assumptions are the brothers of all ****-ups ;). Seriously, though, if it's actually threaded into your frame, drill it out.

Moose
07-13-07, 11:31 PM
I'd try removing it mechanically before taking a drill to the frame. Chances are it'll spin out easily once you find a way to grab on to it.

hiredgoons
07-13-07, 11:47 PM
You don't drill the frame; you drive a drill into the bolt and it unthreads it.

Moose
07-14-07, 05:11 AM
I know, but I'd still try hand tools first. Less chance for regret. But if you have a steady hand and the proper set-up, I'll admit, it's a good way to go.

Ceya
07-14-07, 05:52 AM
Ask Chombo he just went through this.

S/F,
CEYA!

NNNN
07-14-07, 10:09 AM
jeebus, you guys are crazy. just take it to your LBS where there's bound to be someone who has done this before. Have you ever drilled through a bolt before, being careful not to wreck the threads of the thing it's threaded through? Do you have a drill press? Have you ever used a screw extractor? More importantly, do you own a screw extractor? It probably costs as much to buy as it would to have your LBS do the job for you ($10 or so). Plus, if they screw up, it's their fault, not yours. Why risk doing it yourself, especially when you don't even know the correct method for doing so, and ESPECIALLY when you're just going on what a bunch of internet strangers say - people that haven't done it themselves either.

NNNN
07-14-07, 10:12 AM
especially Lisa, but especially Bart.