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Discussion Starter #1
How are my suspension settings effecting my ride?


Rebound damping:
*Rear suspension
Too much rebound damping can cause:
- The rear "jumps" on the bumps instead of following the surface.
- The rear "jitters" under braking.
- It holds the rear down with the result that the bike will understeer!
- It can cause overheating in the hydraulic system of the shock
absorber and make it fade, in other words, it will loose damping when
hot.

Too little rebound damping can cause:
- The rear "tops out" too fast under braking, causing the rear wheel to jump
- The bike feels unstable.

*Front suspension
Too much rebound damping can cause:
- Oversteering!
- It will give poor grip of the front tire.
- It feels like the front wheels will tuck under in corners.

Too little rebound damping can cause:
- Understeer!
- The front can feel unstable.

Compression damping
Rear suspension
Too much compression damping can cause:
- The rear wheel to slide under acceleration .
-It can give a harsh ride over bumps.

Too little compression damping can cause:
- The rear wheel start to bump sideways under acceleration out of the
corner. - The bike will squad too much (rear is too low), that will
cause the front to loose grip.

Front suspension
Too much compression damping can cause:
- Good result during braking.
- Feels harsh over the bumps.

Too little compression damping can cause:
- Strong diving of the front.

Adjustment advice:
Compression damping should be adjusted together with front fork oil level.

Spring ratio:
Rear
Too hard spring ratio:
- Gives easy turning into corners.
- Makes the rear feel harsh.
- Create poor rear wheel traction.

Too soft spring ratio:
- Gives good traction in acceleration.
- Creates understeer in entry of corner.
- Makes too much suspension travel which will make it difficult to
"flick" the bike from one side to the other in a chicane.
- Will give a light feeling in the front.

Front
Too hard spring ratio:
- Good under braking.
- Creates understeer.
- It feels harsh in the corners.

Too soft spring ratio:
- Gives easy turning into corners.
- Creates oversteer.
- Can cause front to tuck under.
- Bad under braking (diving).

Front fork oil level
First see manual. The modern front fork of cartridge type is very
sensitive for oil Level changes, because of the small air volume Air
inside the front fork works as a spring. The different level of oil
affects the spring ratio from the middle of the stroke and has a very
strong effect at the end of the stroke.
When the oil level is raised:
The air spring in the later half stage of travel is stronger, and thus
the front forks harder.

When the oil level is lowered:
The air spring in the later half stage of travel is lessened, and thus
the front forks are softer. The oil level works most effectively at
the end of the fork travel.

Note: Adjust the oil level according to your manual.




BASIC SETUP - Check the following first:

Forks/Rear Shock - Race sag 25-30 mm, 1 - 1 3/16 inch
Forks/Rear Shock - Street sag 30-35 mm, 1 3/16 - 1 3/8 inch
Check chain alignment. If not correct, sprocket wear is increased.
Proper tire balance and pressure. If out of balance, there will be
vibration in either wheel
Steering head bearings and torque specifications, If too loose, head
will shake at high speeds.
Front end alignment. Check wheel alignment with triple clamps. If out
of alignment, fork geometry will be incorrect and steering will
suffer.
Crash damage, check for proper frame geometry.

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TROUBLESHOOTING FORK DAMPING PROBLEMS

Fork Adjustment Locations:

Rebound adjustment (if applicable) is located near the top of the fork.
Compression adjustment (if applicable) is located near the bottom of the fork.
Spring preload adjustment (if applicable) is generally hex style and
located at the top of the fork.
Forks - Lack of Rebound:

Symptoms

Forks are plush, but increasing speed causes loss of control and traction.
The motorcycle wallows exiting the turn causing fading traction and
loss of control.
When taking a corner a speed, you experience front-end chatter, loss
of traction and control.
Aggressive input at speed lessons control and chassis attitude suffers.
Front end fails to recover after aggressive input over bumpy surfaces.
Solution

Insufficient rebound - Increase rebound "gradually" until control and
traction are optimized and chatter is gone.

Forks - Too Much Rebound:

Symptoms

Front end feels locked up resulting in harsh ride.
Suspension packs in and fails to return, giving a harsh ride.
Typically after the first bump, the bike will skip over subsequent bumps.
With acceleration, the front end will tank slap or shake violently due
to lack of front wheel tire contact.
Solution

Too much rebound - Decrease rebound "gradually" until control and
traction are optimized.

Forks - Lack of Compression:

Symptoms

Front-end dives severely, sometimes bottoming out over heavy bumps or
during aggressive breaking
Front feels soft or vague similar to lack of rebound.
When bottoming, a clunk is heard. This is due to reaching the bottom
of fork travel.
Solution

Insufficient compression - Increase "gradually" until control and
traction are optimized.

Forks - Too Much Compression:

Symptoms

Front end rides high through the corners, causing the bike to steer
wide. It should ride in the middle of suspension travel.
Front wheel bounces over bumps while ripples and bumps are felt
directly in the triple clamps and through the chassis.
Ride is generally hard, and gets even harder when braking or entering turns.
Solution

Too much compression - Decrease compression "gradually" until the bike
neither bottoms or rides high, and control and traction are optimized.

Symptom

Front end chatters or shakes entering turns. This is due to incorrect
oil height and/or too much low speed compression damping
Solution
First, verify that oil height is correct. If correct, then decrease
compression "gradually" until chattering and shaking ceases.


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TROUBLESHOOTING SHOCK DAMPING PROBLEMS

Shock Adjustment Locations:

Rebound adjustment (if applicable) is located at the bottom of the shock.
Compression adjustment (if applicable) is located at the top of the
shock or on the reservoir.
Spring preload is located at the top of the shock.
Shock - Lack of Rebound:

Symptoms

The ride will feel soft or vague and as speed increases, the rear end
will want to wallow and/or weave over bumpy surfaces and traction
suffers.
Loss of traction will cause rear end to pogo or chatter due to shock
returning too fast on exiting a corner.
Solution

Insufficient rebound - Increase rebound until wallowing and weaving
disappears and control and traction are optimized.

Shock - Too Much Rebound:

Symptoms

Ride is harsh, suspension control is limited and traction is lost.
Rear end will pack down, forcing the bike wide in corners, due to rear
squat. It will slow steering because front end is riding high.
When rear end packs in, tires generally will overheat and will skip over bumps.
When chopping throttle, rear end will tend to skip or hop on entries.
Solution

Too much rebound - Decrease rebound "gradually" until harsh ride is
gone and traction is regained. Decrease rebound to keep rear end from
packing.

Shock - Lack of Compression:

Symptoms
The bike will not turn in entering a turn.
With bottoming, control and traction are lost.
With excessive rear end squat, when accelerating out of corners, the
bike will tend to steer wide.
Solution

Insufficient compression - Increase compression "gradually until
traction and control is optimized and/or excessive rear end squat is
gone.

Shock - Too Much Compression:

Symptoms

Ride is harsh, but not as bad as too much rebound. As speed increases,
so does harshness.
There is very little rear end squat. This will cause loss of
traction/sliding. Tire will overheat.
Rear end will want to kick when going over medium to large bumps.
Solution

Too much compression - Decrease compression until harshness is gone.
Decrease compression until sliding stops and traction is regained.
Front Fork Problems
Possible Cure

Race sag too small -
Reduce preload.

Race sag too great -
Increase preload.

Forks compress too far on smooth turns -
Stiffer springs, increase preload.

Forks dive too far (bottom out) -
Stiffer springs, reduce air gap, possibly increase preload.

Always losing front end on corner entry -
Softer springs, adjust weight distribution.

Front end chatters coming out of corners - Softer rebound springs or
main springs, reduce damping.

Bike difficult to turn in -
Softer springs, reduce preload or compression damping, alter steering geometry

Front wheel skips on bumps -
Softer springs, reduce compression damping, increase air gap.

Forks judder when braking on a straight -
Reduce compression damping.

Forks dive too fast -
Increase compression damping.

Forks pump down on fast bumpy corners -
Reduce rebound damping.

Excessive pogo action through chicanes -
Slightly increase rebound damping.

Front end shakes (not chatters) in corners -
Increase rebound damping.

Front end shoots up too fast after braking -
Increase rebound damping.


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Rear Shock Problems
Possible Cure

Race sag too great -
Increase preload.

Race sag too small -
Reduce preload.

Rear squats on acceleration -
Stiffer spring, increase anti-squat angle, slightly increase
compression damping.

Very Harsh ride over ripples -
Reduce compression damping.

Bike wallows - Increase rebound damping.

Rear jacks up too fast on braking -
Increase rebound damping.

Rear end chatters exiting slow corners -
Increase rebound damping.

Bike kicks off ripples or bounces on bumps -
Increase rebound damping.

Rear end pumps down on bumpy corners -
Reduce rebound damping.




LACK OF COMPRESSION DAMPING ( Front Fork )

Front end dive while on the brakes becomes excessive.
Rear end of motorcycle wants to "come around" when using front brakes
aggressively.
Front suspension "bottoms out" with a solid hit under heavy braking
and after hitting bumps.
Front end has a mushy and semi-vague feeling, similar to lack of
rebound damping.


TOO MUCH COMPRESSION DAMPING ( Front Fork )

Overly harsh ride, especially right at the point when bumps and
ripples are contacted by the front wheel.
Bumps and ripples are felt directly - the initial hit is routed
through the chassis instantly, with big bumps bouncing the tire off
the pavement.
The bike's ride height is affected negatively - the front end winds up
riding too high in the corners.
Brake dive is reduced drastically, though the chassis is upset
significantly by bumps encountered during braking.


LACK OF REBOUND DAMPING ( Front Fork )

The fork offers a supremely plush ride, especially when riding
straight up. However, when the pace picks up the feeling of control is
lost. The fork feels mushy, and traction "feel" is poor.
After hitting bumps at speed, the front tire tends to chatter or bounce.
When flicking the bike into a corner at speed, the bike will tend to
"porpoise" or wallow a bit, before settling down. Getting aggressive
with the controls makes it worse. As speed increases and steering
inputs become more aggressive, chassis attitude and pitch become a
real problem, with the front traction feedback going numb after the
bike is countersteered hard into a turn.


TOO MUCH REBOUND DAMPING ( Front Fork )

The ride is quite harsh - just the opposite of the plush feet of too
little rebound. Rough pavement makes the forks feel as if they're
locking up with stiction and harshness.
Under hard acceleration exiting bumpy corners, the front end feels
like it wants to "wiggle" or "tankslap." The tire feels as if it isn't
staying in contact with the pavement when on the gas.
The harsh, unforgiving ride makes the bike hard to control when riding
through dips and rolling bumps at speed. The suspension's reluctance
to maintain tire traction through these sections erodes rider
confidence.



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LACK OF COMPRESSION DAMPING ( Rear Shock )

Too much rear end "squat" under acceleration - bike wants to steer
wide exiting corners (since chassis is riding rear-low/nose-high).
Hitting bumps at speed causes the rear to bottom, which upsets the chassis.
Chassis attitude affected too much by large dips and "G-outs" -
steering and control become difficult due to excessive suspension
movement.


TOO MUCH COMPRESSION DAMPING ( Rear Shock )

Ride is harsh, though not quite as bad as too much rebound - however,
the faster you go the worse it gets.
Harshness hurts rear tire traction over bumps, especially during deceleration.
There is very little rear end "squat" under acceleration.
Medium to large bumps are felt directly through the chassis - when hit
at speed, the rear end kicks up.


LACK OF REBOUND DAMPING ( Rear Shock )

The ride is plush at cruising speeds, but as the pace increases, the
chassis begins to wallow and weave through bumpy corners.
Poor traction over bumps under hard acceleration - rear tire starts to
chatter due to lack of wheel control.
Excessive chassis pitch through large bumps and dips at speed - rear
end rebounds too fast, upsetting chassis with a pogo-stick action.

TOO MUCH REBOUND DAMPING ( Rear Shock )

Very harsh ride - rear suspension compliance is poor and "feel" is vague.
Poor traction over bumps during hard acceleration (due to lack of
suspension compliance).
Bike wants to run wide in corners since the rear end is "packing down"
- this forces a nose-high chassis attitude, which slows down steering.
Rear end wants to hop and skip when the throttle is chopped during
aggressive corner entries
 

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This is incredible! Thanks so much for taking the time to type it up!! Very useful for us guys/girls that need more input on our suspensions work!! Thumbs up!
 

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Discussion Starter #3
Thanks but I just got it from Traxxion Dynamics. I've always kept a copy folded beside a mini flathead in my tail.
 

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The mechanics behind suspension are complex that having a symptom-cure list like this is great! Perfect for going down the road of suspension perfection.

Similarly, using the symptom-cure style, looking at tire wear can also aid in setting suspension.

Race Track Motorcycle Tyre Wear Guide - Types and Causes


@Kevin.H since this is titled Part 1, I'm guessing more parts to come?
 

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It's definitely an art that's never ending.
 

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I'm finding the 959 to be highly resistant to a proper setup that will work when roads are anything but glass smooth, (not going to happen here in North Texas I'm afraid ). :frown2:


I have been all over the suspension clickers on my 959 and have yet been unable to find the right combination that will give a high degree of chassis pitch control while still contending with corner entry bumps and midcorner chop as seen in the recent Cycle World test video.




My take is the frameless design is at least, partially to blame here. This has been well discussed in the 1199/1299 Panigale forums but is just now surfacing in the context of the 959. This is probably due to the much friendlier torque delivery characteristics of the baby Panigale. On a glass smooth track, I could probably set the 959 up to handle perfectly but on the real roads around my neck of the woods, (think choppy) the 959 is resisting my best efforts to find the sweet spot compromise settings that will allow me to push the bike hard in the bumpier corners. Stiff compression and rebound settings get the chassis pitch issue under control but then are too harsh to handle the chop. Conversely, I've found backing off to standard settings handles the bumps but then leads to a high degree of chassis pitch causing the bike to wallow down into a corner. Not exactly confidence inspiring. It may turn out that there is no perfect solution that will give me the best of both worlds and I might just have to learn to ride it as is. (ala Casey Stoner and the Ducati GP07)
 

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The Italians are well known to be experts on tuned flex in bicycle chassis and the same with motorcycle chassis to give "feel". Historically, the defacto frame of choice was always the trellis steel space frame that Ducati, MV Augusta, et al are so fond of and had developed to a very high degree.


They got away from this on their Desmocedici MotoGP bikes to save weight and try something different and have had problems with the issue of front end feel ever since. Rossi couldn't buy a podium finish on the GP bikes, Hayden didn't do much better.


Apparently there is something to this and I have to wonder if this isn't some of what I am seeing with the frameless Panigale chassis design? It does feel different and not in a good way in my perspective. Remember, when a motorcycle is pitched over 45 degrees or more in a turn, the traditional suspension is no longer working optimally and tuned flex built into the chassis is responsible for the tires ability to track ground abnormalities generating the feedback riders refer to as "feel". If you're not riding you're motorcycle very hard, you'll most likely never notice this; but bury the front end in a corner and the chassis is very important in communicating to the rider what is going on at the front contact patch.


Interestingly, I've heard this is one reason that BMW abandoned it's WSBK program with the S1000RR after several unsuccessful seasons. Their engineers supposedly could never come to grips (no pun intended) with the riders need for this unquantifiable sensation of control at the front tire contact patch. You can't put numbers to it, you just have it or you don't and it only shows up in data from the laptimes and corner speeds.
 
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