I removed the Öhlins shock the other day and, rather than have the bike off the road, I thought I'd refit the Sachs shock but try it with the spare Öhlins 115N/mm spring. I was interested to see, firstly, if it would fit and, secondly, if it improved the ride quality of the, frankly, very basic Sachs unit.
The first thing to do is to remove the old spring. Now, when I swapped springs on the Öhlins, it was very straightforward; there's sufficient thread on the preload adjuster to allow you to remove the spring collar without a spring compressor. Not so on the Sachs; even with the preload wound right down, the spring is still under compression and the collar won't budge. A quick tip: wind off the preload rings with the shock on the bike, they're very difficult to turn on a loose shock.
Fortunately, I bought some spring compressors for the Öhlins shock, (which I didn't actually need), so I was also keen to try them out. It's a bit tricky to get the compressors on the Sachs spring because, being progressively wound, the coils get closer together at the end and there's not much room to fit the hooks. You can see from the picture that I fitted them to the middle three coils and, after turning the compressors equally and alternately, there was enough clearance to slide out the collar.
Here are the Öhlins and Sachs springs side by side.
Fitting the Öhlins spring was easier simply because the coils are evenly spaced and there's plenty of room to attach the hooks.
The Öhlins spring fits the Sachs shock perfectly as you can see:
So, not too onerous to change; from start to finish, wheels back in the ground, 40 minutes.
I'll post again once I've had a chance to road test it and see if it has improved the Sachs shock.