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R1 Biker
24/08/2005, 14h18
Set rock hard you will just skip over everything. People often make the mistake of tuning everything super hard for harder riding. That's a no no. Ever watch roadracing? WHen they brake the front end slams down onto the fender, and when they accelerate just the opposite happens...

A great set up is hard to find if you dont know what you are doing. First get your sag set and then work on 1 thing at a time. Take notes that way you will know how each adjustment has affected your ride. If you simply crank the compression up, along with rebound, raise the forks, and adjust the preload all at once, and the bike rides worse than it did-then what adjustments made the difference?

I'm no to expert for sure but the suspension of your sportbike is one of the "gray areas" that alot of us are lacking knowledge in. It might be what gets you 3 seconds on the track, or helps you keep up with your riding buddy... Study up!

Here is something that might help:

The Ultimate Suspension Tuning/Trouble Shooting Guide

Forks

1. Bottoms, Too Soft, Wallows
Ask Questions: Under what kind of conditions?
Does it feel good otherwise?
Does it feel too soft everywhere?
A. Oil Level too low.
B. Not enough low speed compression damping
C. Not enough high speed compression damping
D. Spring rate too soft
E. Not enough Spring Pre-Load
F. Dirt in valving, broken valve, bur on piston or shim
G. Damping rod bushing worn out – (Pre 95 KYB problem)
H. Compression valve o-ring broken
I. Damping rod not attached to cap

2. Too Stiff – Deflects, Harsh, Nervous, Twitchy
Ask Question: Everywhere or just on the square edge bumps?
A. Too much compression damping adjustment – HS & LS
B. Too much compression damping internally – HS
C. Spring rate too stiff
D. Too much low speed rebound damping
E. Oil level too high

3. Rides low (Dynamic) – Oversteers
A. Spring rate too soft
B. Not enough pre-load
C. Not enough low speed compression damping
D. Increase low speed damping adjustment, valving stack or go to a single stage valving stack
E. Low speed rebound too high
F. Anything that makes the rear higher than the front

4. Rides High – Doesn’t Turn, Understeers, Pushes
A. Too much Preload
B. Spring rate too high or stiff
C. Too much low speed compression damping
D. Rear riding too low
E. Forks air pumping up – replace seals
F. Anything that makes the rear lower than the front

5. Dives Under Braking (Static)
A. IT SHOULD!
B. On braking, the TOTAL dive is controlled by spring forces (Rate, Pre-Load, Air) only, NOT DAMPING
C. See “Rides Low”

6. Sticky Forks
A. Axle clamp not centered – align tubes
B. Bad fork brace adjustment
C. Seal not broken in or poor after market design
D. Seal not lubricated
E. Poor quality oil or wrong viscosity
F. Bent tubes, bent axle, bent triple clamps
G. Dented or bent sliders
H. Poor bushing design on upside down forks
I. Outer tube anodizing worn through
J. Forks air pumping – replace seals
K. Triple clamp too tight
L. Misaligned fork tube height – GMD
M. Forks not broken in – (twin chamber Showa)
N. Damaged or worn bushings
O. Metal in bushings
i. Pre-Load washers not located properly
ii. Aluminum Pre-Load washers (what were those engineers smoking)
iii. Steel spring spacer directly on aluminum cap
iv. Bottom-out system needs chamfering – KYB
v. Fork caps “shedding” on installation
P. Cartridge rod bushing too tight
Q. Spring guide rubbing on ID of spring or guide growing from solvent
R. Fork spring OD too large

7. Doesn’t Turn
A. See “Rides High”
B. Rear end rides too low
C. Spring Rate too stiff
D. Too much Pre-Load
E. Too much Tire Air Pressure
F. Poor tire type/compound
G. Riding Style
i. Not weighting the front end
ii. Elbow down riding – Dirt
iii. Sitting too far back – Dirt
H. Seat too low
I. Bars too high

8. Feels Lose
A. Not enough low speed rebound damping
B. Not enough high speed rebound damping
C. Damping rod bushings worn out – KYB typical
D. Steering bearings lose or worn
E. Swing arm pivot or linkage bearings loose or worn
F. Tire pressure too low
G. Chassis flex
H. Worn out rebound piston ring
I. Worn out fork oil
J. Cavitation

9. Headshakes
A. Steep fork rate or not enough fork trail
B. Chassis not straight – GMD
C. Chain adjuster off creating misalignment of wheels
D. Fork Flex, Chassis Flex, Swingarm flex – Steering damper
E. Fork oil level too high
F. Bottom out mechanism too long
G. Not enough low speed rebound damping
H. Too much rebound damping
I. Too much high speed compression damping
J. Tire air pressure too high
K. Poor tire selection
L. Tire not mounted correctly or cord not straight
M. Wheel out of balance
N. Brake rotor bent
O. Worn out or lose steering head bearing – tighten to that they drag slightly
P. Anything that make the front end lower than the rear
Q. Death grip on the bars

10. Deflects on square edge bumps
A. Too much high speed compression damping
B. Spring rate too stiff
C. Too much Pre-Load
D. Too much low speed compression damping
E. Yeah sure see “Sticky”

11. Leaky Seals – Wheelies do not and will not cause seals to leak!
A. Nicks in the tubes
B. Bent tube
C. Worn bushings
D. Improper installation
E. Old Seals
F. Fork tube too smooth

More info:
http://www.2wf.com/articles/how_to/...AD39F35A8E9.asp

mamarina
24/08/2005, 20h28
I guess you don't have problems with your suspension..... :)

Mamarina

R1 Biker
24/08/2005, 23h49
I guess you don't have problems with your suspension..... :)

Mamarina

not yet :lol:
how u doing by the way ...hope all is good ... :)

mamarina
25/08/2005, 13h28
Can't complain. :D ....knowledge is very hard to teach.. :roll: .but eventually you'll all learn... :D :D :lol:
Power is nothing if u can't keep the bike down and have control....... :D :D

Hope u are doing well...Did u get your suspension done finally.... :)


Ride Safe...
Mamarina :D

R1 Biker
25/08/2005, 14h53
Can't complain. :D ....knowledge is very hard to teach.. :roll: .but eventually you'll all learn... :D :D :lol:
Power is nothing if u can't keep the bike down and have control....... :D :D

Hope u are doing well...Did u get your suspension done finally.... :)


Ride Safe...
Mamarina :D

My suspension are adjusted .. but for next year i might change them .. i'll keep you posted

mamarina
27/08/2005, 20h00
mamarina is noisy :roll: to know who adjusted your suspension.....do tell...... :?:

mamarina :D

R1 Biker
27/08/2005, 20h15
mamarina is noisy :roll: to know who adjusted your suspension.....do tell...... :?:

mamarina :D

picotte performance ( Paul ....Pascal Picotte Personal Mechanic) :D :D :D :D :D

Ghost Rider
06/02/2008, 09h26
Here is something I had found years ago. Not sure where I got it from, but I've used it ever since and it works. :)

Trouble Shooting Motorcycle Suspension Problems

Adjustment locations: Forks

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.


Lack of Rebound

Symptoms:

• Forks are plush, but increasing speed causes loss of control and traction

• The motorcycle wallows and tends to run wide 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.


Too Much Rebound

Symptoms:

• Front end feels locked up resulting in harsh ride.

• Suspension tucks in and fails to return, giving a harsh ride. Typically after the first bump, the bike will skip over subsequent bumps and want to tuck the front.

• 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.


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.


Too Much Compression

Symptom:

• Front end rides high through the corners, causing the bike to steer wide. It should maintain the pre-determined sag, which will allow the steering geometry to remain constant.

Solution: Decrease compression "gradually" until bike neither bottoms nor rides high.

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.

Symptom:

• Bumps and ripples are felt directly in the triple clamps and through the chassis. This causes the front wheel to bounce over bumps.

Solution: Decrease compression "gradually" until control is regained.

Symptom:

• Ride is generally hard, and gets even harder when braking or entering turns.

Solution: Decrease compression "gradually" until control is regained.


Adjustment Locations: Rear Shock

Rebound adjustment (if applicable) is located at the bottom of the shock. Compression adjustment (if applicable) is located on the reservoir. Spring prelude 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 in, 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: Decrease compression until harshness is gone. Decrease compression until sliding stops and traction is regained.