Suspension black magic

So I installed a Cogent rear shock and set the sag to around 35mm thinking I didn't want the bike to be too firm considering I haven't touched the front just yet. I haven't played with the damping, but after a test ride I was wonder where I need to head with it. The bike soaks up the bumps fine now, probably more so than the OEM rear, but on a reasonable bump the bike kind of rocks and then settles. Should I roll of the compression, or is it more the fact that the new rear shock is showing up the soft front more than the OEM ever did? I'm new to suspension tuning btw, all of my bikes I've just ridden with factory setting.

Its going to be a trial and error thing.
I`ve had my Wilbers now for three years, and I`m still playing with it. One setting won`t do all, so that's the beauty in being able to adjust it.
I`ve read and read, and I got sick of reading. But I still say you should go to race sites, that some expert has given his 2 cents worth of information, and try to weed out what you yourself, thinks is right and wrong.  
 I now, just note what does what, for different road conditions.
Probably the best thing you can do is, start in the middle settings, go for a ride, make a mental note what the bike was like, then select either the rebound or compression, and go extreme hard, then extreme soft, again making mental notes what the bike did, then wind it 6 clicks at a time, until you start getting close to what feels right. When you start getting ball park, only move it one at a time until it feels right.
Then do the same with the opposite damper control.
If its wet, I soften the setting. If its a bumpy piece of crap road, again I soften the setting. If its wavey, I firm it up a fair bit.
If its super smooth and windy, I crank them both up. I never dial and leave it. That's the reason for having adjustable suspension.

Just have a play, and familiarize yourself with the shock.

I think once I have it close I'll leave it alone, but until I firm up the front with the racetech gear I think the see saw effect will most likely remain

Even though you haven`t done the front yet, you should be able to eliminate a lot of the unstable nature your feeling.
What does it feel like its doing!  Does it feel like the rear itself is bouncing around, like its got a hinge in the centre of the bike?

In the big picture, the bike should be better, not worse than OEM right now.
I`d definitely try and wind both of them up.

Don`t give up yet, have a play.

It feels like it won't settle after hitting a big bump. For anything else it is firm but damped.

Try increasing your rebound straight away.

The compression, you want to try and get it as hard as you can, to the point where its not compressing your spine when you hit a bump.

If its cranked all the way, it should feel violent when you it a whoop or bump. Just keep turning it back to the point where its bearable.
If the compression is too soft, the shock wont support the bike when its under the pump, and you will loose stability.

Rebound, you want to try and set it so the wheel is still tracking the road. Too soft, and it will pogo, too hard, and it will skip on corrugations.

Even the best of shocks, won`t dampen a violent pothole, and its still going to be a compromise in settings, that you will have to learn for yourself.
I try to set the bike for whoops, rather than bumps, meaning, it will be on the firm side.

I bought a new Cogent for my 05 1200s from Holeshot a few years back and when I got the sag to what I thought I just played with the damping setting generally increasing it.

The Cogents come with a couple of spring rates, did you get the one best suited to your weight.

Masterblaster wrote:I bought a new Cogent for my 05 1200s from Holeshot a few years back and when I got the sag to what I thought I just played with the damping setting generally increasing it.

The Cogents come with a couple of spring rates, did you get the one best suited to your weight.

You and Reddog are neighbours, go help him out.

Need a track day to tune it I reckon

I've got the red spring, which should be fine for my 85Kgs. Not 100% sure though as this shock has seen 2 owners before me in @jaba01 and @nic 2 and I can't find much information on the net with regarrds to Cogent other than whats on Dale Walkers site.

Reddog, watch this to give you a basic idea.

https://www.youtube.com/watch?v=keInRV2N6-w

This second is some expert, so I guess what he says is right, but I tend to disagree with his end statement,
due to our roads are nothing like a race track, so I`d soften the rebound for the road.
I`m no expert...what would I know.

https://www.youtube.com/watch?v=SXDL_jREhEE

You will notice that the two blokes probably know a thing or two about suspension, yet the second contradicts the first one.

The first one says there`s a setting for the road, and the second says don`t touch the rebound.
So I like I say, play with it till you feel its right for you.

reddog wrote:Need a track day to tune it I reckon

I've got the red spring, which should be fine for my 85Kgs. Not 100% sure though as this shock has seen 2 owners before me in @jaba01 and @nic 2 and I can't find much information on the net with regarrds to Cogent other than whats on Dale Walkers site.

I have found the best damping indicator for me is on a road that has a good surface but also has some dips along the way that you can hit while cranked over accelerating through a bend. How the bike settles upon rebound is always a good indicator for me.

There is no separate compression/rebound damping on my Cogent just the 1 adjuster, the shocks are supposed to be speed sensitive according to the manufacturer.

Dale Walker & his partner at Cogent recommend that the shocks be serviced every 2 years which I think includes an oil change. Mine has never been serviced and it has now done 37000 kms and I haven't noticed any degradation.  

I might consider taking it to Russell at Dynotime at some stage in the future for a service, he is the guy that I got to fit my fork valves & springs after I dropped the forks.

reddog wrote:Need a track day to tune it I reckon

I've got the red spring, which should be fine for my 85Kgs. Not 100% sure though as this shock has seen 2 owners before me in @jaba01 and @nic 2 and I can't find much information on the net with regarrds to Cogent other than whats on Dale Walkers site.

I meant to say I will dig out what documentation was supplied with the shock and when I find it I will send you a copy.

Cheers @masterblaster from what I have read the adjuster on the cogent is for rebound. From what is happening and what I am feeling I would presume the rebound is too soft. I'll experiment this week on the way to and from work. I know for a fact that too large a sag setting makes for an interesting two up ride. When I had my wife on the back a few days ago before looking at the sag the bike felt horrid. Corners I'd normally be able to carry 130+ I was riding at 100 due to the terrible seesawing

From memory mine has about 23 different clicks (settings) for the damping and if you were looking up at the base of the shock from ground level the damping increases when turning the dial in a clockwise direction.

Since originally fitting the shock I have dropped it out to lube all the pivot points for the rear suspension including the swingarm. I think Suzuki might have been rationing grease when these bikes were assembled.

Any bike with basic adjustment (front and rear preload plus rear rebound adjustability) can be gotten spot on by two simple rules.

First set your sag before going to damping.  The only choice you have to make is to use one quarter of total travel or one third.

One quarter gives more travel to absorb large brake and throttle inputs and decreases the chance of bottoming out but increases the chance of topping out and causing chatter on broken surfaces. It also gives more ground clearance when the suspension is compressed while cornering with large lean angles.
One third is used for normal road riding which gives the best balance against either topping or bottoming out.

Altering preload has no other effect except raising or lowering the resting position of the fork/shock.
Set your front first with you on it. Once it is set it doesn't need to be changed. The load on the bike does not affect it.
Setting the rear is dependent on the weight you have on board. Single rider, rider with luggage and rider plus pillion all need increasingly larger preload settings. If you want to reduce your workload set it to the average weight carried. (remote preload setting is the shiz for this)

Then you only have rear rebound left. Get it into the ballpark as the guys above have said - if your arse is pogoing, rebound is too fast (that's too soft if that's how your shock is marked but I try to never use the words hard and soft because those two words have caused mass confusion among motorcylists). If your arse "packs down" over a series of bumps rebound is too slow (too hard if you must).
Once you get it in the ballpark watch your tyre wear. If the edges on the tread on the tyre shoulder form a lip on one edge and are rounded on the other then rebound is not exactly right.
Check this guide on wether you need to increase or decrease rebound:

http://biketrackdayshub.com/motorcycle-tyre-wear-guide/

If its not right, change rebound by a few clicks in the direction shown above and give the tyre a few hundred kilometres to wear into the new pattern. Rinse and repeat till the tread edges are smooth and even. Then the rebound is spot on - for the time being. Rebound is a stand alone adjustment - it is not affected by any other changes but it does change as your fork/shock oil gets older. Damping oil loses viscosity with mileage and both compression and rebound damping become faster and eventually just sacks out altogether. Fork oil needs to be changed at 24000k max and shocks need servicing at 50000k max (more often is better but is expensive to service a shock) When your oil goes off your settings are out the window.

mtbeerwah wrote:
You will notice that the two blokes probably know a thing or two about suspension, yet the second contradicts the first one.

The first guy is a journalist, the second guy is a suspension technician - I'll stick with number two

My seal kit from all balls racing arrived yesterday. Looks like I'll be on the tools this weekend doing a front fork rebuild.

#Tag wrote:

mtbeerwah wrote:
You will notice that the two blokes probably know a thing or two about suspension, yet the second contradicts the first one.

The first guy is a journalist, the sec
ond guy is a suspension technician - I'll stick with number two

Dually noted, but I still don't nessessarily agree with having the same rebound setting for track and field.
I still feel you can afford to stiffen your setting for a track. There are some atrocious roads in Australia,
and particularly where I live, and I do play with my setting to suit the needs of the conditions,
and in these conditions, one setting won't do.
Again, I`m no technician, so what do I know, but I know what feels right for me, and if its ripped up or massively wavey, I`ll back off the rebound. If its smooth and grippy, I`ll tighten it up, and as the journo said, that I do agree with, it quickens your steering, and makes it more precise.