Rockshox coil – setting sag

Does anyone else have issues setting sag on a Rockshox coil shock? I’m using the bottom out bumper and the sag markers.  Unfortunately the bumper catches on the inner edge of the coil and this gives me false sag readings.  It’s not a problem when the bumper is pushed to the bottom, it’s only when setting sag and the bumper is near 25-30%.

I didn’t notice what was happening for several weeks and was wondering why things didn’t feel right. The bumper was only being pushed to around 25% and then getting caught on the spring and compressing, not being pushed any further. So i was always getting a 25% reading when in reality, it is closer to 30%.  I kept running lighter springs to get to 30% sag.

I’m considering trimming the bumper slightly so it doesn’t hit the spring.

Any thoughts or suggestions before I take to the bumper with a  sharp blade?

If you’ve now got a selection of springs, fit the ones that rides the nicest?

Sag is only ever a starting point really and there’s not much you can do about it with a coil. It’ll sag as much as it wants to under your weight.

Open up all the twiddlers on the damper and go by how it feels to ride.

If your bottoming out or using all the travel to easily, go up a spring.

Once your happy with the travel you’re using, start adding damping if you think you need it.

(Add rebound along the way to stop the back end kicking you off though)

Alternatively, get someone to measure your shock’s eye to eye length whilst you’re sat on the bike & work out sag this way.

A mate used on of these for a while when he was setting up a new bike.

Reverse Travel and Sag Indicator 2.0

use the RS trail head app as a step 1.

Mine was really close to start with

Splodge of grease on the shaft up by the seal head, the seal pushes it down the shaft as the shock compresses. Measure.

I went really hi-tech and tied a piece of string on the shaft to check sag at home. I took it off before riding obviously

String or grease! Brilliant, thanks guys ?

Grease worked a treat 🙂

I have the same problem checking the sag on the coil on my enduro but mainly because the shock is so tucked away in the frame I can barely even see the shaft.