Seatpost clamp bolt

Page may contain affiliate links. Please see terms for details.

SRanger

Guest
Should a bolt with pre-applied threadlock which doesn't include a washer be used on a seatpost clamp? I went to the LBS yesterday and the worker gave me M5x20mm bolt with the pre-applied threadlock and no washer (see photo). My original bolt was a M5x18mm bolt with no pre-applied threadlock and had a washer included.

What LBS gave me:

IMG_20220527_171231.jpg


IMG_20220527_171320.jpg


My original bolt:

IMG_20220527_164702.jpg


Thanks.
 

Ajax Bay

Guru
Location
East Devon
Threadlock is only appropriate if the bolt is going to stay fastened for a long time. A seatpost clamp bolt is not in that category. And a washer will help getting a consistent fastening torque on the seatpost clamp. I have just checked one of my frames and the seatpost clamp bolt has, surprise, surprise, got a washer. You don't say why you are replacing. I'd prefer a bolt with a bit of rust (or slightly bashed head - see OP image) and a washer than a new one with no washer. (The threadlock will wear off with successive unfastenings (eg to clean the seat post on a planned preventative maintenance basis).)
 
Last edited:

Ajax Bay

Guru
Location
East Devon
Or, as the packet says "chainring bolts" (clearly not)!
20mm seems extraordinarily long for bottle cage bolts.
The extra 2mm (cf current) doesn't matter, except, perhaps aesthetically.
 
OP
OP
S

SRanger

Guest
Can't you re-use the washer?

It was difficult removing it
 
OP
OP
S

SRanger

Guest
I tried removing the washer and I made myself bleed. I can just add a separate washer but is a washer really important? Most people say their seat clamp bolt doesn't have a washer.
 

Ajax Bay

Guru
Location
East Devon
As Ian says: the restriction on the washer is that the bolt head (and washer) has to go into a recess (normally). Anyway OP is only seeking to replace because the bolt head's a bit scratches (aiui).
 
Top Bottom