Subject: shock spring swap Thu Mar 14, 2024 6:47 am
I (80 kg/180 lbs naked, around 90 kg/200 lbs with gear) was as incontent with my rear shock as many. Opposite to what many riders do I took the preload off the rear spring and voilá the scolded Sachs-shock became way more compliant. But as the spring is overwhelmed when riding two-up I had searched for options besides spending big bucks on new shocks (Wilbers 800 Euro, Öhlins 1.350 Euro, ...). I ended up giving Hyperpro a chance, as I had good experience with a progressive Wirth-spring on my DR 650. Hyperpro does not give any data of spring-weight, as the springs seems to be wound progressively and therefor becomes harder the more you compress it. In this respect you can´t compare it with a linear spring (f.e. stock spring). Getting the GRiSO off the ground and the shock out was a journey, the next - unexpected one - followed suit: Most dealers and shops change shocks, but nearly nobody swaps springs. After an odysee I stranded at the 4th dealer - Ducati, as they utilize Sachs-shocks as well - and again was told that "we can´t do it". But I was lucky, as an experienced mechanic came over, had a look and just stated "Nah, it´s just a matter of 10 minutes." Exactly 10 minutes later he returned my shock with the Hyperpro-spring and the recommended preload (1 cm/0,4") and received his tip. An hour later both tires were back on the ground. Now for the ride-impressions: Weather only permitted a short test. I was expecting to be able to reduce compression and having to increase rebound (as the stronger spring needs to be "tamed" more), but this was only partially true. The reduction in compression improved ride-quality and compliance, while the rebound was still too slow. Now the bike follows undulations and imperfections way better without becoming wallowy or intransparent in the faster stuff. The best of all this: The spring and the tip were 150 Euro alltogether - a fraction of a new shock, but with very satisfying results. At least for riders approx. in my weight range and presumably up to 100 kg/220 lbs this mod gets a
EDIT: The Italian shop [You must be registered and logged in to see this link.] recommends this spring up to riders of 100 kg plus pillion of further max. 80 kg, = max. 400 lbs altogether.
Last edited by el capitan on Fri Mar 15, 2024 8:18 am; edited 1 time in total
Charlie J and mickfinn like this post
paulbrice GRiSO Capo
Posts : 1532 Join date : 2015-01-04 Age : 63
Subject: Re: shock spring swap Thu Mar 14, 2024 12:34 pm
Most motorcycle suspension shops have a quick bench setup to compress and remove/change rear springs. I use Sealey tool which isn't ideal but easily does the job - useful if you want to experiment with different spring options (regular springs are roughly Euro30 each).
Subject: Re: shock spring swap Thu Mar 14, 2024 12:45 pm
I was told by shops that they either
a) have no tools for this b) have tools for cars and state that those are too big for the smaller motorcycle-shocks that provide less distance between spring and shock-body
I could have bought a spring compressor for 50 Euro or waited for a cheaper online-order to arrive, but wanted to put the bike back on its wheels asap. With my DR 650 I don´t need a spring compressor at all, as the spring can be "unloaded" and dismounted without special tools.
A linear spring (even Öhlins) would have cost half of what they charged me for the progressive one. But it seemed like a universal solution that is also suitable when riding with luggage (rare) or pillion (rare as well).
Edit: As unusal as it sounds - THE suspension specialist is in the countryside about 250 kms from home.