Hi Guys, Can anyone enlighten me on the function of the balance valve on this shock? Im pretty okay with the function of the low speed compression and rebound adjusters on the top of the shock, 32 clicks of adjustment each, but the instruction manual page as below... Shows that the balance valve has 16 clicks of adjustment for High speed compression / rebound Can someone enlighten me on how this works, what it controls and how to set it up? Because the manual doesn’t explain what it does or what it affects? Am I right in thinking that the 32 click low speed comp/rebound adjustment controls the “ normal” range movement of the shock when the bike is moving and the 16 click Hi speed comp/rebound adjustment control steps in when you hit a bigger than normal bump that threatens to kick you out of the seat? So if you find a big bump threatens to ping you off the seat, you can come out a few clicks with the Hi speed compression adjustment to lessen the impact of the bump? Is that what it’s for?? I should add here that I haven’t had chance to experiment on the road with the setup as the bike won’t be taxed until April, but I’m a bit mystified by what it’s supposed to do really,..any clues guys??
I'm not familiar with this particular damper but I have built and developed dampers for racing cars for quite a few years. By the look of it your compression and rebound adjusters are what I would call bleed adjusters. They let you adjust the amount of oil that can flow across the piston and have the most effect when the speed with which the damper shaft moves is low. We are talking a speed of 0 to 50mm per second or so. At higher damper speeds the amount of oil that bleeds through those adjusters will saturate and the valving ( shim stacks on the piston) starts to work. It looks like this damper has another shim stack which I believe only works in compression (bypass adjuster ). If the forces go above a certain value that valve bypasses the bleed adjusters all together and let's the oil flow into the canister. If I'm right, I'm 95% sure I am, then your are correct and the bypass is a blow off valve that works at very high damper speeds and reduces damping dramatically when you hit a big bump. From what I read there, all the adjusters have there full stiff setting when they are turned fully clockwise. That setting us referred to as zero. Then you count the clicks anti clockwise and end up with 32 or 16 respectively being the settings providing the least damping.
Cheers Petsmith, I think your terminology is bang on when you call it a “blow off valve” and it makes sense when you say that the normal adjusters can’t flow enough oil through them and this will create a kind of hydraulic lock and that’s what you feel kicking you out of the seat. Standard setting is middle of click numbers for each of these adjusters, so I think I’ll trial it up the same stretch of road , same speed hitting same bump and tune in the bypass valve until I get the least kick but still feeling controlled,..a bit of trial and error is called for I think
I think this animation shows it a bit better.. From 50 secs onwards you can see the shim stack in the bypass valve doing it’s “ blow off” thing, seems to make a bit more sense to me now?
I have this shock and all I can say is it’s so good that at my pace - high end of inters - the ride is so good that I have never found the need to play with it. People have talked to me about the rough patches and bumps on track - like those that are supposed to exist on the exit of the foggy esses at Donington and I just look blankly at them. This shock plus changing to the flat rate linkage from 1199/1299 transformed the 959 for me.
The bumps are there for sure. I found them every lap at last years Ducati day on the 996 with Nitron shock
I’m a little concerned I might have too soft a spring in there for my weight but on the bumpy bits my current setup seems to just allow me to ride through it all without drama. I’m probably losing out in other areas and will start to suffer under hard braking and acceleration if i ever get that far!
Or you have found a good (the fast) line there. On my Triumph behind @Advikaz i did not notice the bump. I would have been on a ‘straighter’ line. On the Duke I was on my own I felt I was running wider on the exit which is where the bump is.
More by good luck than good management for me. I hadn't ridden at that track in the previous 10 yrs, so was just feeling my way around.
