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Discussion Starter #1
I've read through various threads here about how to adjust the rear shock and sag setting. Fiddled about with the rear shock adjusting it around the recommended settings and factory setting.

Though it seems to be all to no avail. The rear is just too stiff and transmits jolts up through the seat and also upsetting the front.

So I've decided to replace the shock and thinking either Wilbers Type 640 Road or Nitron NR1. As I ride solo and no luggage I don't see the point of multi adjust-ability of the shock so basic set up will be as it comes from the factory.

What do others recommend, bearing in mind my budget is max £500/$660. (I'll fit the shock myself)
 

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I have Wilbers 640 fitted to the rear and it was a big improvement over stock. Nitron are great too, and perhaps due to the weakness of the Pound to the Euro, you may find Nitron very competitive price-wise nowadays.
 

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I don't see the point of multi adjust-ability of the shock so basic set up will be as it comes from the factory.
The fact that you find the rear shock not right for you would suggest that you do need a replacement that is adjustable. Shocks from the makers are setup for the average rider with an average riding style on average roads. Once setup you can leave alone and enjoy the ride.;) I think you will regret not spending the extra when you find the supplied shock lacking.
 

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Outside temperature, the rider, shock oil condition and road riding condition effects the suspension.
Unless you use your bike to commute only on the freeway on a straight line, then I would be fine tuning the suspension all the time.
 

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Discussion Starter #9
Good run out today, ended up with 0 Pre load and 2 turns on Rebound.

On a ripply road the back end is like a jack hammer following every bump and ripple. Not had a bike like this before, we tried various settings and it really didn't make much difference.

I hit a pothole which almost had me out of the seat and my mate hit same pothole on his Triumph Sprint (New YSS shock) and he just felt the bump never even left his seat.

The spring is way too stiff for this bike.
 

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I can only speak to the UGS, but theres way too much compression dampening. Unfortunately, this is non adjustable. So you're working against the spring and the comp dampening. You kinda have to forget about the standard sag and go by feel if you will. Not good...
 

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... there's way too much compression dampening...
That is the big problem the OE shock has, unless you weigh more or less the 180-190 lbs which seems to be about what the shock is sprung for. Then you also have a spring rate problem.

Definitely set the rider on sag. 35mm is about right with 120mm wheel travel. Get it close to that. Go 40mm on the longer travel UGS.

Then play with the rebound damping. Turning the adjuster clockwise (turning it in) increases rebound damping. Turn the adjuster CCW (out) all the way. Have someone hold your bike upright so you can push down on the seat with both hands. Push hard. Observe how the rear extends, bounces back up. "Rule of thumb" for rebound is the seat shouldn't quite keep up with your hands when you lift them up after pushing down on the seat. Too little rebound and you're riding a pogo stick. Too much and the shock "packs down" and feels stiff. It's easy to put in too much rebound damping. It does kinda make the rear end feel more controlled but ride quality suffers and the tire won't stay hooked up.

Turn the rebound adjuster way out, CCW. Ride and see how it feels. Screw it in a half turn at a time. See how it feels as you change it. Too little and it's bouncy and has some funny ride motions, too much and it packs down and becomes stiff. There's a happy point between the two.

"Just enough" is right, more is not better. What you learn here will also apply to an aftermarket shock.
 

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Discussion Starter #12
That is the big problem the OE shock has, unless you weigh more or less the 180-190 lbs which seems to be about what the shock is sprung for. Then you also have a spring rate problem.

Definitely set the rider on sag. 35mm is about right with 120mm wheel travel. Get it close to that. Go 40mm on the longer travel UGS.

Then play with the rebound damping. Turning the adjuster clockwise (turning it in) increases rebound damping. Turn the adjuster CCW (out) all the way. Have someone hold your bike upright so you can push down on the seat with both hands. Push hard. Observe how the rear extends, bounces back up. "Rule of thumb" for rebound is the seat shouldn't quite keep up with your hands when you lift them up after pushing down on the seat. Too little rebound and you're riding a pogo stick. Too much and the shock "packs down" and feels stiff. It's easy to put in too much rebound damping. It does kinda make the rear end feel more controlled but ride quality suffers and the tire won't stay hooked up.

Turn the rebound adjuster way out, CCW. Ride and see how it feels. Screw it in a half turn at a time. See how it feels as you change it. Too little and it's bouncy and has some funny ride motions, too much and it packs down and becomes stiff. There's a happy point between the two.

"Just enough" is right, more is not better. What you learn here will also apply to an aftermarket shock.
With 0 preload, and 0 rebound we tried to set the sag, and could get about 22mm sag at the back, (as front is non adjustable)

I weigh 90kg (198lbs) fully kitted, have single seat and no luggage.

We then went for a ride and tried adjusting rebound as you suggested, there was minimal improvement, when I initially picked up the bike set up as factory settings the bike would run wide into corners.

I've come from the RT LC (with electronic suspension) and I could get that bike well over and hustling along county roads no problem. But this bike ?? I think if I weighed another 30lbs it may be okay-ish.

I'm getting the Nitron R1.
 

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With 0 preload, and 0 rebound we tried to set the sag, and could get about 22mm sag at the back, (as front is non adjustable)

I weigh 90kg (198lbs) fully kitted, have single seat and no luggage.

We then went for a ride and tried adjusting rebound as you suggested, there was minimal improvement...
I'm surprised you're only getting 22mm sag. "Sag" is "rider on", feet on the pegs so all your weight is on the bike and is the difference between fully extended (bike on the sides stand and laid over a bit so the rear wheel is of the ground and the "all your weight on the bike" figure. Just so we're using the same frame of reference, there are several that are used that can confuse the issue. When "working with what you've got", "rider on" sag is what counts. Zero rebound is the adjuster turned fully out, fully CCW. Been a while since the stock shock was on mine but at your weight I'd expect zero preload and rebound adjuster turned fully (or near fully) out, fully CCW. I weigh about 10kg more fully kitted.

The stock shock sucks. No way to put it nicely. I outlined how to try to make it work as well as possible. You don't have much to work with. I went with Ohlins but there are many good options. The Ohlins are definitely sport bike oriented. Others may be more comfort oriented, any can be if you can get them to actually set them up (valving/shim stacks) for your weight and purpose. More than just changing springs....
 

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Discussion Starter #14
At 0 preload and 0 rebound, we tipped the bike over onto its side stand so the rear wheel was off the floor, got a measurement, at exactly 20". Actually when we sat the bike upright, no rider the measurement was the same.
Then I sat on the bike same settings full kit on, feet up and bike balanced, the sag measured 19 1/8ths" so sag was 7/8ths of an inch or about 22mm.

My bike has single seat, no rear pegs/subframe and high level Akra pipe.

What sag do others get in same situation ?
 

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At 0 preload and 0 rebound, we tipped the bike over onto its side stand so the rear wheel was off the floor, got a measurement, at exactly 20". Actually when we sat the bike upright, no rider the measurement was the same.
That sounds wrong. Not your measuring but the spring preload. Like the adjuster isn't fully backing off. Might hose it with WD-40 or similar and run it thru its' range of adjustment a couple times. See if it will back off further. Lean on it a bit, be "persuasive".
 

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I'm no race driver, just love riding the canyons in SoCal. Absolutely not happy with original rear shock on my 2016 R9T, finally I got a Bilstein, adjusted incl. right spring for my weight. It's another world!
 

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Discussion Starter #17
That sounds wrong. Not your measuring but the spring preload. Like the adjuster isn't fully backing off. Might hose it with WD-40 or similar and run it thru its' range of adjustment a couple times. See if it will back off further. Lean on it a bit, be "persuasive".

I'll have another go with it tonight, will lift the bike so it's clear of the floor, unwind both rebound and preload. One thing I did notice is the first 1 or 1.5 turns on the preload are loose with no tension, is this normal ?
 

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One thing I did notice is the first 1 or 1.5 turns on the preload are loose with no tension, is this normal ?
That is normal. There's some "slack" in the mechanism.

Be careful with the rebound adjuster. You can damage it, it's a needle valve. The preload adjuster you can lean on some. Run it thru its' range of adjustment. I'm hoping it's just hung up... Your measurements show excessive preload. The shock is still junk but less preload would make the rear suspension work better.
 

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Discussion Starter #19
Right, I wound up the preload a few times, didn't touch the rebound, then I jacked the bike up, got measurement with no preload and no rebound, then got the bike back on the ground, no difference to measurement.

I had the wife sit on the bike with weight a bit over my kitted out weight, the sag measured 24mm. What I need to know is what measurements are others getting so I can go back to dealer with a case for a new shock or contribution to Nitron/Wilbers.

On the other thread a measurement of 1.4" (is that 1 1/4" ?) is given as sag, but I'm obviously not getting near that.
 

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I'm no race driver, just love riding the canyons in SoCal. Absolutely not happy with original rear shock on my 2016 R9T, finally I got a Bilstein, adjusted incl. right spring for my weight. It's another world!
Who sells that?
 
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