Aaaaarrrrggghhhhh !

I am so close to completing my new Liteville build.

Finally my x-fusion sweeps arrived (yes I am looking forward to the trails coming alive) but when I try to mount my XO Trails using the 40 mm mount adapter supplied it all goes Pete tong. In short the calipers sit too far from the rotor and the pads barely make contact.

Without the adaptor the caliper is too close, only tightening down to the fork mounts when in the dip of the wavey edge of the rotor

I’ve been on the Sram site and identified what I believe to be the correct combo of parts. It’s a 160mm travel fork and if I read the chart correctly the this requires the 40mm adaptor. It occurs to me that the 160 referred to in the chart may mean the size of rotor which can be mounted direct without adaptor but this isn’t made clear – anyone know which it is ?

If the latter then if the fork is designed for direct mount of 180mm rotor then the 20mm adaptor is the way forward. Unfortunately the x-fusion site provides no info on this so right now it’s a guess.

In writing this I may well have answered my own question but does anyone have any first hand experience with this issue so I don’t start ordering random adaptors willy nilly.

Post mount forks and calipers are generally set to work without an adaptor at 160mm, so you’ll probably need a +20mm adaptor if you have a 180mm rotor.(Please note the lack of commitment to saying it’ll definitely work, i’ve been around the farce that masquerades as cycling’s standards for too long-see next post re rotor sizing)

Have a look at the SRAM parts manual, page 52 I think. It’s got a good description of all the adapters.

Might be worth checking rotor size too. I got a kit for 180 but it wouldn’t fit as my rotors were actually 183, it is that tight.

Looks like the x-fusion sweep is a 180 post, which means you’ll need a 200mm rotor with the 20P spacer kit for the xo trails. Not sure why but it looks like a 180 rotor on a 180 post is not supported (page 50) so probably won’t fit.

Thanks for the comments. I’ve been all over the SRAM website technical stuff like a cheap suit and it’s pretty good. The problem is that xfusion don’t state the rotor size their fork has been designed for (without adaptor).

Based on the grief so far I can only assume that it’s 180 and so I need the 20p adaptor to fit my 200 rotors. One on order but that’s another couple of weeks of watching my pride and joy sit in its stand .

Sadly, my desire for everything to be just so on such lovely newness means I simply can’t ride it with an old 180 rotor. It would feel like driving your brand new car out of the showroom with a set of nicely kerbed alloys ! I”ll carry on getting the Ventana filthy in the meantime.

Based on the grief so far I can only assume that it’s 180 and so I need the 20p adaptor to fit my 200 rotors. One on order but that’s another couple of weeks of watching my pride and joy sit in its stand .

Why, just go into pretty much any LBS and get one off the shelf – and then you can ride over the break.

Sadly LBS is utterly hopeless unless requiring puncture repair !! I did try.