Seat post shim in Scott CR1 HMX frame?

luv2ride

Hi all. Given I can't get my Scott to ride "softer" with bigger volume tyres due to lack of frame clearance I thought I might try a Canyon VCLS leaf Spring seat post. Trouble is they only come in 27.2mm diameter and my frame takes 31.6mm I think. I also remember reading the various info / warning tags that were attached to the frame when I built it up and distinctly recall one saying "Never use a spacer or shim in the seat tube". Short of invalidating the warranty, what other issues might there be?
Is anyone successfully using a reducer shim in their CR1, or Foil, frames?
cheers

lpretro1

If it is a cf frame then it would not be a good idea to try and stick a metal shim in it - the danger of fracturing the frame would be quite high I should imagine

6wheels

If you can find a plastic/carbon shim (definitely not metal) around 100mm length which has a good fit for post to shim and shim to seat tube then, I don't think you'd have any problems. It's something I'd do with a frame of modest cost, but not with one costing £3K or more.

Ask your local bike shop if they've got any shims you could try out.

Rightarmbad

I have one and find the frame a good ride over broken surfaces.
This is the bike they use for Paris-Roubaix after all.
25mm tyres fit in fine and at that size my 90kg only needs 105psi in the back tyre and 98 in the front.
If you need a softer ride than that, maybe consider a carbon rail seat.


But to continue with your question, Scott specifically warn against shims and it will void your warranty if you crack the seat tube.
I'm presuming here that it is less than 5 years old and still has warranty.

But really, this is one of the best riding frames around, I suspect that you suffer from 'pump my tyres up way hard in the misguided belief that it is faster' syndrome.

keef66

As long as the shim is as long as the inserted seat post I don't see what difference it makes. 31.6 mm seatpost or a thinner one with a shim.

I may well try it on my CR1. Always struck me as odd that they design a frame with SDS stays and all that stuff, then mount the saddle on a 31.6 scaffold pole.

luv2ride

Think I'm going to try 320tpi tyres first off as they've also been a recommended upgrade. A bit cheaper than the seatpost + shim option currently. As for pressures, I regularly run 85-90 psi so they're certainly not contributing to the "harshness" of the ride. TBF, I took it out on Sunday (lovely and dry so first time it'd been out for a while) and it was certainly better than I remembered. Think I've grown accustomed to the larger volume tyres on my winter bike and cross bikes though over the past few months!