Breaking saddle rails- need suspension seatpost ?

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gentlegreen
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Breaking saddle rails- need suspension seatpost ?

Postby gentlegreen » 26 Mar 2015, 2:37pm

I'm rather heavy at 18 stone / 114kg and ride a roadified MTB - higher gearing, relatively narrow tyres pumped up hard...

For quite a few years I had a Rockshox suspension seatpost which eventually failed - first one of the clamp bolts, then the casting itself and I'd started doing longer distances and was getting fed up with the imprecision of setting saddle height - I seem to be fairly sensitive to this and am not one to stand up to pedal on hills...

I replaced it with a bog standard single bolt rigid post and have now broken the rails of three saddles just ahead of the clamp. (also the tensioner nose on a Brooks and a Spa Nidd)
It isn't as though I just sit there like a sack of potatoes when I hit bumpy stuff - which is often on my somewhat rural commutes, but inevitably it happens sometimes.

So I mean to replace the seatpost and I'm wondering if I should use a suspension post until such time as I get back to my fighting weight of maybe 14 stone ?

pwa
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Joined: 2 Oct 2011, 8:55pm

Re: Breaking saddle rails- need suspension seatpost ?

Postby pwa » 26 Mar 2015, 3:31pm

I once broke steel saddle rails and put it down to the clamp having sharp edges. I smoothed the edges down and had no further problems.

If I were worried about my weight I would stick to steel rails.

A suspension seatpost might save your saddle, but the post might be tested.

Brucey
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Re: Breaking saddle rails- need suspension seatpost ?

Postby Brucey » 26 Mar 2015, 3:32pm

the traditional approach is to use a sprung saddle. Worth thinking about?

Another approach is to reinforce the saddle rails. One way of doing this is to cut some steel tube (with the ID to match the OD of the saddle rails) lengthwise and use it to extend the saddle clamp (which will also have to be modified). If you can make the clamp twice as long you might well reduce the bending stresses accordingly.

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~

Dave W
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Re: Breaking saddle rails- need suspension seatpost ?

Postby Dave W » 26 Mar 2015, 8:57pm

There's a thudbuster on Gumtree at the moment I saw the other day. Long travel version with the larger diameter seatpost.

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gentlegreen
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Location: Bristol
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Re: Breaking saddle rails- need suspension seatpost ?

Postby gentlegreen » 26 Mar 2015, 9:08pm

I fancy one of those with the handlebar lever - would make traffic lights less of a pain as I get older - though these days I hop off the saddle.