Suspension Tuning

[jestal]

Seems to me the majority are shouting for suspension upgrades for a smoother ride over bumps. Buy a goldwing.
Fine suspension adjustment is for the track. Expensive replacement shocks are for the track.

Uh...no. What "we" want is nice controlled ride quality over all bumps and under all conditions. Plush is nice but not at the expense of bottoming out over the next large bump and loosing control.

********. The more expensive shocks contain rate sensing damping and position sensiing damping that is even more important for street performance than track performance. That is why ALL the upper end performance cars are being equiped with very expensive dampers and using electronic control and intervention in the shock technology to make street cars with high performance levels that are also liveable on the street. Street cars have shock technology that is outlawed by most racing sanctioning bodies because of the cost. Once again....racing shocks are easy compared to street shocks. What works on the track is a very narrow spectrum of the street requirements. It takes a lot of (expensive) technology to make a street shock work under both conditions.

 

[rocket]

I will be brief and tell you how I improved my knowledge and understanding of suspension components and how to adjust a suspension. I purchased the DVD "Suspension for Mortals" by Max McAllister of Traxxion Dynamics. It provided me with straight forward information and cleared up the "black magic" of working on my own suspension. I knew, or thought I knew a lot about suspensions from reading and other peoples advice. Bull! Most of the advice was way off base and applying what I read was a little flustrating. The video showed me what I needed to know and how to work on my own stuff. There may be better videos out there but I know this one worked for me. If you have someone else dial in your suspension then you will be afraid to touch it. I think you need to learn how to do it yourself. First you get it in the ballpark and then tweak it in.

One of the most important things I have learned over time is this. Your basic motorcycle suspension comes set up for a rider of about 150 lbs. Therefore, for most American riders the suspension is "under sprung" the day you pick it up at the dealer. Depending on your weight, you may be able to dial in your preload front and rear without running out of adjustment. If not, then spring upgrades are needed for your weight on your specific bike.

I said I will be brief and so I will end this. Hope this is of some help. I know that tuning the suspension for your weight will vastly improve a bikes handling and a great handling bike is a fast bike.

 

[Cdogman]

Thanks........ I will see if I can get a copy. Good post

 

[HaulinAshe]

I adjusted the suspension as per Jeff Ashe and it was a marked improvement over the way I had it originally set.

Axeman or Jeff, what settings are you gents using? Im about 260lbs with my gear on, ride my 06 pretty hard on the lumpy backroads of New England.....looking for the best setup I can get out of my stock 06 suspension.....thanks.

GAPS,

Sorry I didn't respond quickly. I've been gone all weekend seeing how well an 07 slides on ice and gravel. :angry2:

To set/adjust suspension you must start with five tools; bathroom scales, service manual, pencil, notebook, screwdriver. I'll explain...

* Weigh yourself fully clothed, helmet, gloves, boots and all, on a set of digital bathroom scales. Write that number in your notebook and date it.

* Weigh the contents that you normally carry in your sidebags. If you also use a top bag, backpack etc., weigh them all and record that number in your notebook as one lump sum of "cargo".

* Sit down and read the service manual section on Tuning The Suspension so that you thoroughly understand where all the adjustments are and how to change them. It's not rocket science, just pick an evening when the SO wants to watch a chik flick and pretend you are interested.

* Write in your notebook what Yamaha says your factory default settings are for; Front preload (lines), Front compression (clicks), Front rebound (clicks) and Rear rebound (clicks).

* Now go turn all your clickers fully clockwise CAREFULLY counting the clicks as you go and record that set of numbers in your notebook with a date.

Are you set to stock? Many brand new bikes are not. If you've never run the stock setups (for real) then set them that way and go test ride.

At 260 lbs. of rider weight, my setups are probably not going to be ideal for you, but they may be close. Here's the linky to my now ancient thread. I hate to retype.

Haulin Ashe Suspension settings for 05

You might consider closing/counterclockwise the front compression by two(2) clicks.

I'm foggy tonight so I didn't catch the year of your bike. It it's an 05 or older, you definitely are overdue for fork service. Get some fresh 10 wt. shock fluid in those nasty-*** forks. You'll thank me later. If all else fails, try raising the oil level from 100mm (Yami default) to 90mm. Don't bother with anything higher because you should go elsewhere with your efforts.

I'll try to be blunt here, which should be really easy for me...

Write everything down before and after you touch anything. You have to know where you are at to have any idea where to go.

I'll spend money on anything that makes a difference I CAN FEEL. If after adding/changing something from stock, I can't feel the difference immediately in the bike, then it comes off and gets sold. I believe strongly in working with the stock configurations as much as possible before blowing them off for aftermarket.

Having said that I will add that in the pre-06 bikes, the rear shock has an established history of being sub-standard for riders over 200 lbs. net weight. Remember, Japanese dudes that weigh over 200 lbs. don't typically ride Yami, they typically wrestle and Yami engineers are notorious for designing bikes for 5'8" tall, 165 lb. "Americans". Most of us have one ***-cheek that meets that standard.

Hope this helps. Did you get your notebook yet?

 

[GAPS]

I adjusted the suspension as per Jeff Ashe and it was a marked improvement over the way I had it originally set.

Axeman or Jeff, what settings are you gents using? Im about 260lbs with my gear on, ride my 06 pretty hard on the lumpy backroads of New England.....looking for the best setup I can get out of my stock 06 suspension.....thanks.

GAPS,

Sorry I didn't respond quickly. I've been gone all weekend seeing how well an 07 slides on ice and gravel. :angry2:

To set/adjust suspension you must start with five tools; bathroom scales, service manual, pencil, notebook, screwdriver. I'll explain...

* Weigh yourself fully clothed, helmet, gloves, boots and all, on a set of digital bathroom scales. Write that number in your notebook and date it.

* Weigh the contents that you normally carry in your sidebags. If you also use a top bag, backpack etc., weigh them all and record that number in your notebook as one lump sum of "cargo".

* Sit down and read the service manual section on Tuning The Suspension so that you thoroughly understand where all the adjustments are and how to change them. It's not rocket science, just pick an evening when the SO wants to watch a chik flick and pretend you are interested.

* Write in your notebook what Yamaha says your factory default settings are for; Front preload (lines), Front compression (clicks), Front rebound (clicks) and Rear rebound (clicks).

* Now go turn all your clickers fully clockwise CAREFULLY counting the clicks as you go and record that set of numbers in your notebook with a date.

Are you set to stock? Many brand new bikes are not. If you've never run the stock setups (for real) then set them that way and go test ride.

At 260 lbs. of rider weight, my setups are probably not going to be ideal for you, but they may be close. Here's the linky to my now ancient thread. I hate to retype.

Haulin Ashe Suspension settings for 05

You might consider closing/counterclockwise the front compression by two(2) clicks.

I'm foggy tonight so I didn't catch the year of your bike. It it's an 05 or older, you definitely are overdue for fork service. Get some fresh 10 wt. shock fluid in those nasty-*** forks. You'll thank me later. If all else fails, try raising the oil level from 100mm (Yami default) to 90mm. Don't bother with anything higher because you should go elsewhere with your efforts.

I'll try to be blunt here, which should be really easy for me...

Write everything down before and after you touch anything. You have to know where you are at to have any idea where to go.

I'll spend money on anything that makes a difference I CAN FEEL. If after adding/changing something from stock, I can't feel the difference immediately in the bike, then it comes off and gets sold. I believe strongly in working with the stock configurations as much as possible before blowing them off for aftermarket.

Having said that I will add that in the pre-06 bikes, the rear shock has an established history of being sub-standard for riders over 200 lbs. net weight. Remember, Japanese dudes that weigh over 200 lbs. don't typically ride Yami, they typically wrestle and Yami engineers are notorious for designing bikes for 5'8" tall, 165 lb. "Americans". Most of us have one ***-cheek that meets that standard.

Hope this helps. Did you get your notebook yet?

Jeff, thank you for the heap of info, judging by what you have here it seems I am close to getting it right. Axeman has sent me some info regarding his setup which he arrived at following your instruction, between the two Im sure to get this puppy dialed in. I plan to start over after recording my existing settings, BTW, Im on a 2006 so I do not plan to change fork oil till next season, by then Im hoping you will have a nice recipe for tweaking the stock 06-07 bits B)

Just for the record, I LOVE MY FJR and the people involved here at the forum are don't suck either.

 

[ducpilot]

I hope this helps ... This is information given out at a suspension clinic held at SportBike NW last month by Puget Sound Safety (they also offer the Lee Parks Total Control Advanced Riding clinic and a street course at Pacific Raceways)

www.pugetsoundsafety.com 253 531 4585

Start with the basics:

• Fork and shock sag should be set around 1/3 of its total travel ( 25-35 mm for most street bikes)

• Properly align the chain. If this is not correct the bike will corner improperly and sprocket wear will be increased.

• Ensure the tires/wheels are balanced, If the wheels are out of balance, you may experience a vertical vibration and headshake.

• Set tire pressure (start with the OEM recommendations not the Max sidewall pressure)

• Check steering head bearings and torque specifications (if too loose, there will be head shake at high speeds.)

THE MOST COMMON ISSUE IS THE RIDER! :dribble:

Fork Adjustments

Rebound adjustment is located near the top of the fork.

Compression adjustment is located near the bottom of the fork.

Spring preload adjustment is located at the top of the fork.

Shock Adjustment

Rebound adjustment is commonly located at the bottom of the shock

Compression adjustment is located near the top or on a remote reservoir

Spring preload is located on a ramp adjuster or double collar and thread at the top or bottom of the shock spring

Static Sag = L1 – [ (L2 + L3) / 2 ]

L1= suspension free length

L2= rider, gear & bike, suspension raised and settled gently

L3= rider, gear & bike, suspension compressed and settled gently

The answer is your sag (you want around 1/3rd of the total travel, if your adjustments are near max or minimum then you need a different spring rate)

Initial set-up

1. Set Static sag (25-35 mm) and check for free sag (front 5-10 mm, rear 1-5mm)

2. Check for excess stiction (Front <10 mm good, >20mm bad, rear should be near 0)

3. set rebound and compression settings to manufacture recommendations or to the middle of their adjustment range

4. Tune fork rebound

a. Front end should rebound and settle only a few mm, less for heavy rider, more for light riders (up to 15 mm)

b. For sport riding set as describe and then slowly tune out settling to 0mm

5. Tune fork compression (this is difficult to do static and needs to be done during test rides)

• Softer = comfort

• Harder = sport (excess = headshake on bad roads or high speeds)

6. Tune shock rebound

• Press down hard, bike should return to full ride height in less that 1 second with a visible delay at the end of its travel (too much rebound = BAD)

7. Tune shock compression (difficult to tune static… take it for a test ride)

a. Ad more for sport riding or heavy loads

b. Less for Touring comfort, rough roads, or light weight riders

Front Suspension Tuning (Forks)

Lack of Rebound

• 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 at 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.

Too Much Rebound

• Front end feels harsh.

• Suspension packs causing the bike to skip over subsequent bumps and wants to tuck the front.

• With acceleration, the front end will tank slap or shake violently due to lack of front wheel tire contact.

Lack of Compression

• 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 suspension is compressed a clunk is heard due to bottoming the fork travel.

Too Much Compression

• 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.

• Front end chatters or shakes entering turns. This is due to incorrect oil height and/or too much low speed compression damping.

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

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

Rear Suspension Tuning

L

ack of Rebound

• 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.

Too Much Rebound

• Ride is harsh, suspension control is limited and traction is lost.

• Rear end will pack, forcing the bike to run wide in corners due to rear squat. It will slow steer because front end is riding high.

• When chopping throttle, rear end will tend to skip or hop on entries.

Lack of Compression

• The bike will not want to turn in or feels heavy.

• Suspension may bottom causing a loss of control and traction.

• Excessive rear end squat, when accelerating out of corners, the bike will tend to steer wide.

Too Much Compression

• 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.

• Rear end will want to kick out when going over medium to large bumps.

Damping - Damping is how the speed of your suspension is controlled through the process of converting energy to heat. This is done by controlling the speed of oil through the suspension by using a series of holes or valves . Damping is speed sensitive not position sensitive.

Preload – This is the amount of load (compression) being applied to the spring in relation to its free-length (non-compressed state). A common misconception is that preload changes spring weight… it does not.

Rake – Angle of neck at normal chassis attitude

Sag / Static Sag- is how far the bike compresses between fully extended and how far it compresses with the rider onboard.

Free Sag – This is the amount the bike settles under its own weight with no rider on board.

Stiction – Amount of friction resistance there is to start suspension parts moving. Static + Friction = Stiction

Suspension Travel – Total movement from top to bottom of fork / rear shock

Trail/ Caster – Length made by a line from rake angle to vertical line measured from center of axle spacing in normal motorcycle attitude, this is the self-righting.

Always make small adjustments, more is not always better.

Keep notes. Suspension tuning is an art, be patient.

 

[TruWrecks]

Finally!!!!!!!1 Someone gets it right!

I did a tuning class with Fluid Suspensions last Spring. They gave us the same information. My FJR now handles like a true sport bike. I've been shredding tires in corners, and the bike felt completely stable.