seat post clamp help
10-21-20, 10:05 PM
#1
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seat post clamp help
I have an old hard tail mountain bike with a 27.2mm dia seatpost. I want to add another clamp above the seatpost clamp for extra clamping to help keep it from sliding down. All I want is a clamp with 27.2mm inside diameter. Nothing else. I find a ton of them with I.D. for clamping around the seat tube, for example 31.8mm ID. Doesn't seem like it would be that hard to find a clamp with 27.2MM I.D. but I can't find one.
10-21-20, 11:01 PM
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Sorry if this is a weird question, but -
do you want that extra clamp-above-the-clamp there to REALLY prevent the seatpost from sliding down, [like, because the lower, "real" clamp at the top of the seat tube is not keeping the post up] ...
or just for a bit of extra convenience [say, to prevent the post from sliding down annoyingly when you loosen the main clamp, or when you're putting the post/seat back in] ?
Cause if it's the former, I'd just figure out why the post/original clamp are not keeping things in place, and if the latter, I'd use the mounting ring for a light or reflector to do that.
do you want that extra clamp-above-the-clamp there to REALLY prevent the seatpost from sliding down, [like, because the lower, "real" clamp at the top of the seat tube is not keeping the post up] ...
or just for a bit of extra convenience [say, to prevent the post from sliding down annoyingly when you loosen the main clamp, or when you're putting the post/seat back in] ?
Cause if it's the former, I'd just figure out why the post/original clamp are not keeping things in place, and if the latter, I'd use the mounting ring for a light or reflector to do that.
10-21-20, 11:04 PM
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I have an old hard tail mountain bike with a 27.2mm dia seatpost. I want to add another clamp above the seatpost clamp for extra clamping to help keep it from sliding down. All I want is a clamp with 27.2mm inside diameter. Nothing else. I find a ton of them with I.D. for clamping around the seat tube, for example 31.8mm ID. Doesn't seem like it would be that hard to find a clamp with 27.2MM I.D. but I can't find one.
I think I have found an easy solution. I didn't know there were twin seat psot clamps avaiabe. I found one with the bottom half that clamps on to 31.8 and the top half clamps to 27.2. Problem solved.
10-21-20, 11:06 PM
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I have an old hard tail mountain bike with a 27.2mm dia seatpost. I want to add another clamp above the seatpost clamp for extra clamping to help keep it from sliding down. All I want is a clamp with 27.2mm inside diameter. Nothing else. I find a ton of them with I.D. for clamping around the seat tube, for example 31.8mm ID. Doesn't seem like it would be that hard to find a clamp with 27.2MM I.D. but I can't find one.
10-21-20, 11:33 PM
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as you’ve discovered, seatpost clamps are sized to accommodate the seat tube in addition to the seatpost. Maybe look for a clamp designed for a 25.4mm seatpost. Of course, if you simply want to prevent the seatpost from slipping down, and your current clamp is preventing rotation, might a simple (albeit ugly) hose clamp around the seatpost do the job?
The bike is an old beater I use to run to the store a couple of blocks away. I don't do much for it like I do my road bikes, it's too crappy for someone to steal so it makes a good store runner. 
Don't want to invest too much for the clamp. The one I found was $40 plus shipping. Maybe I will just forget about it. The hose clamp works it just looks dorky 
10-22-20, 07:47 AM
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10-22-20, 08:12 AM
#8
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I used a hose clamp for two years until my bike needed a drive train replacement. Lbs changed it out for a regular seat post clamp, without even asking me!. The nerve!
