Halfords bike faulty - what are my rights?

Nasqueron

Has anyone suggested/tried carbon paste? Stuff is designed to reduce slippage on carbon frames where you can't clamp it tighter than a certain amount? If 18nm isn't holding it's that's some seriously bad design, most of my carbon bike stuff like that is much lower and doesn't move

rdr

as a keen cyclist and an engineer I would make the following comments about that setup.

• 18 Nm is quite a lot for a bike many bolts are half that.
• That is a hex head bolt that you are going to struggle to get a socket on due to the saddle, torque spanners exist, but I am not sure how many bike shops will have one. It could be that it is not being torqued up correctly.
• I cannot be sure from the photo but it appears that the saddle rail is touching the post as a point other than the clamp as well, in that case it will work loose eventually.

my plan to try and sort this out would be:

1. check that the saddle is only contacting the post in the clamp and not at the back as well.
2. Put some blue Loctite on the bolt
3. re-tighten the bolt to the necessary torque, you may have to resort to a spring balance on a spanner and some calculations.

Herzlos

From the picture it looks like it wants 5-8Nm, and most bike torque wrenches will fit on that, though car ones won't. My bike has a similar mechanism and it's fine.

Have you been in touch with Boardman directly? I'd expect them to be pretty good to deal with since they are a reputable brand.

If it's been replaced and still failing then I'm leaning towards something being incorrect in terms of setup, and unfortunately the bike techs in Halfords are pretty hit and miss.

Is it the original saddle? What parts are carbon?