Ohlins Rebound damping adjustment

[PeterT]

I have a 2005 V11 with the Ohlins suspension and I wish to play around with the damping to improve cornering on bumpy roads that I find is not as good as my other bike.  Firstly, does anyone know what the Ohlins fork model was (was it the FG43?) or if not, where I can get the right Ohlins technical manual on-line? (The link for this item in the V11 forum that gives links to the manuals (fork, rear and steering damper) does not now seem to work).  I do have the FG43 manual as a PDF file and when I replaced the oil, it looked to be the right one.  This says that the damping at the top of the forks has a total travel of 20 clicks but when I check my actual forks it is 32; hence my worry that i've not really identified the right Ohlins manual for them.  It does not say in the Moto Guzzi manual what the model the forks are, only that both compression and rebound are set 13 clicks away from fully (clockwise) closed.  Also, if the forks are FG43, then the Ohlins manual says rebound is adjusted at the top of the fork and compression at the bottom but my MG owners manual says exactly the opposite.  Which is right?  

[PeterT]

I seem to have confirmed the mistake in the Moto Guzzi manual regarding rebound and compression damping adjustment by the simple expedient of fully closing off the top-fork adjuster and then the bottom fork adjuster.  It is really obvious that the bottom fork adjuster is the one that adjusts compression damping since you get a very hard response when you suddenly push down hard on the handlebars.   Fully closing the rebound damper at the top of the fork is less obvious as the rebound is just damped, whereas fully opening it there is a marked overshoot as the forks come up after being compressed.  So the MG manual is wrong and this does line up with the FG43 Ohlins manual.   This still leaves the question as to whether the Ohlins forks fitted are based on the FG43.  

Unless my search skills are defective I don't seem to find much in this excellent forum on damping adjustment.  There is some on sag adjustment but not, it appears, on damping.  Please correct me if I'm wrong on this.  I have been looking at the Dave Moss Tuning Youtube videos and reading round on the subject and it would appear that the problem I've got in navigating a series of S-bends near my home that are a bit bumpy where my line gets thrown out, is more likely caused by having too much rebound damping.  This causes the front wheel to deload after bump compression, allowing it to slide sideways and definitely giving a less precise feel and loss of confidence to the rider.   I will experiment and report back once the weather has warmed up.  We are in a blast of arctic air for the next few days here in the UK.

[gstallons]

I have not seen (w/my own eyes) Ohlins forks to know if they have ID or serial #s to identify production or model of these forks .  after everyone gets up , hopefully someone over here can provide input . Have you contacted Ohlins for help ?

[PeterT]

The Moderator has very helpfully checked and given me the links to the manuals that didn't seem to work from the threads I found that gave them on this site.   He says they work now.  This shows the forks as being the FG43.  Interestingly, I contacted Brooks of Bradford, a specialist Ohlins repair and refurbishment specialist here in the UK that refurbished and replated my front forks 4 years ago.  (They have worked brilliantly ever since without any oil leaks in probably 15-20kmiles, something that was giving me a problem before in spite of changing the seals).

I asked them if they had any record of what model they thought the forks were and got the answer FG313.  I got the manual for this as well and there does not appear much difference between the two.  The only thing I noticed was that the compression damping adjustment in both shows the 3mm Allen key at right angles to the bottom of the fork while my adjustment is much nearer 30 degrees to the axis of the fork, with the Allen key angled upwards, as shown in the MG owners manual.  They said that Ohlins often made non-standard forks for particular bikes that, while based on one of their standard designs, often incorporated differences and I guess in the V11 case this meant a different casting at the bottom of the fork to incorporate the brake calliper attachment.  This probably explains the difference in the angle of the compression adjustment.

[PeterT]

I guess I started this thread with the aim of collecting anyone's experiences in playing about with the suspension damping.  Before the weather and winter set in here in the UK (it is now dark at 16.00hrs, it is often frosty at night so salt is being spread on the roads and they often remain wet most of the day - not a good combination for a m/c!)

Anyway, before this set in I did have on late afternoon ride.  I reduced front rebound damping by 2-clicks and there was a slight improvement cornering around slightly bumpy "S" bends.  I therefore softened the front by a further 2-clicks anti-clockwise (Ohlins say you shouldn't adjust by more than 2-clicks at a time) and the rear by 2-clicks.  The result was a definite improvement without any perception that the ride was any softer or would be any worse on smooth, bends.  Perhaps because I had not softened the compression damping.  The bike felt more "planted" on the road and whereas I took the bends at 52mph on the original setting it gave me more confidence to take them at about 64 on the 3rd run.  I do feel there is some more adjustment to go, but I must admit to being pleasantly surprised by its affect so far.

[GuzziMoto]

My general thoughts on rebound dampening is I want just enough to control the rebound action of the spring and no more. I tend to either start with too little and add it until it feels like it is under control, or you can go the other way and have too much and keep reducing it until you start to feel loose, then add a couple clicks back. You can even get a decent starting point by bouncing the suspension statically, for a starting point you can bounce the suspension and add or subtract rebound to where when you bounce down on the suspension it rebounds back fully but does not overshoot. If it overshoots on the up swing and then settles back to ride height I probably don't have enough rebound dampening. But I don't want much more then what is required to prevent that overshoot. If you do bounce it to see what you have, be sure to do so with you on the bike. You can even sit on the bike while someone else bounces it.

My own tastes run to minimal compression and rebound dampening, just enough to control the springs, with springs on the firmer side. I prefer to let the springs support the weight, and I just want enough dampening to control the springs. I tend to prefer starting with too little dampening and add dampening until it is under control. But you can certainly start at the other end and reduce dampening until you find that sweet spot as well.