Oh no, Suspension Woe

[glennis]

Hi,

I have a pair of Ohlins shocks on my R1200GS Adv of which the hydraulic preload assembly on the rear has crapped itself (BM607). I was advised that the preload adjuster is usually the first thing to fail on a heavily loaded GS so I was not really surprised after a year and a half and 35000kms of rough terrain that it had failed.

So, I took the shock off the bike and removed the hydraulic preload unit and replaced it with a new locking collar. I am riding 2-up with luggage within the max load limits for the bike and the shock has an uprated spring (think its the 160nm per unit of whatever length)

With the shock reinstalled and the spring preload where I thought it was (stupid that I did not mark it) I have a ride height of 81mm which according to the Ohlins manual it should be around 30mm. I am worried that if I continue to add more preload to achieve the stated ride height that the spring will be over compressed and have limited travel remaining.

Is the Ohlins manual ride height etc correct for these types of bikes or are these settings for street bikes? Also what is the maximum spring preload that can be placed on the shock?

Hope this all makes sense.

Cheers

 

[Magwych]

IIRC I beleive I read somewhere on the Ohlins setup that the max preload on the rear spring is 17mm.

Loosen off the preload collar, count the number of turns! I usually use a dab of touch-up paint, or a marker pen, to mark one of the notches to help with the counting.
Measure the free spring length, then wind the preload collar down about 11 turns. Measure the spring length now, it should now be 17mm shorter, make any small afjustments if not. It should very close, the thread is 1.5mm per turn. Count the number of turms too, hopefully it is more than you unwound it!
That is now at the maximum designed pre load, and you can recheck your rider sag; it should be about 65-70 mm (30%-33% 210mm travel).

I'll see if I can find the Ohlins specs for you