Educated people: Why - how - what do - "shocks"

[toaster404]

You people know everything, so I have a question.  This springs from my realization that my expensive only new bike I ever got amazing engine California 1400 touring has a suspension that doesn't really work very well.  My wife's $2750 2009 Versys suspension is much much much better.  Even my DL1000 suspension is better.  My rock-bottom Suzuki cruiser suspension was not that much worse. 

This seems unreasonable.

So I have this bike which has a modern engine and what feels like a primitive suspension, at least in the rear.  Undersprung and overdamped.

What is a cost effective way to deal with this thing?

Those Harley dudes have magic (might well be BS) such as http://www.motorcycle-superstore.com/40933/i/progressive-suspension-416-series-air-shock

So maybe I don't understand suspensions on motorcycles.  Or cars, for that matter.

My understanding is that when a force is applied to the wheel, which is always up, the spring compresses.  The way the spring behaves is important.  Fluid management systems slow the response of the spring upward.  Maybe these are speed/force dependent.  Sometimes the fluid is air.  Then there may be systems that provide a different response as the spring extends. Some of these systems are very fancy.

Meanwhile back at the engine, fuel management relies upon measurements of air pressure, humidity, feedback from oxygen sensors, moon phase, and the current testosterone level of the rider. 

Why isn't the suspension electronically controlled?  I can make up several cumbersome and silly systems with a pencil and a few beers.  Sensors aren't a problem.  Servos work reliably and quickly.  The amount of equipment necessary to modify the impedance of a fluid system shouldn't be difficult.  A mechanical spring could be effectively stiffened by locking up thingies between varying numbers of coils.

OK.  Given that electronic systems aren't going to be available to bolt onto my bike, what distinguishes all these aftermarket systems?  That is, what makes them better? 

Springs.  I know different springs are available.  Some claim a progressively increasing spring rate.  Until coils touch, I would think that Hooke's law would apply and the rate would be effectively constant until coils touch, which shorten the spring and change the rate.  I can buy progressive springs working.  But suspensions are moving so little under normal use.  I've tried to see how much the bike's rear end compresses hitting a bump on the Interstate, maybe 1/2" - it doesn't react because of the damping.  Let's say I normally use 2" of travel - can a progressive spring really accommodate this? 

Damping.  I can see how different compression v. extension rates can be achieved.  Also, how more complex valving can allow easy movement for relatively small movements of the suspension, but stiffen up for larger.  Just a hole does that.  I've looked at other fancy systems, but pictures don't tell me exactly how they work and what would be best.

[redrider]

Check the Gostar racing website for suspension set-up. Very informative and you do not need a racetrack. If your spring rate is not right for your weight, the other settings will only mask the problem.

[toaster404]

Check the Gostar racing website for suspension set-up. Very informative and you do not need a racetrack. If your spring rate is not right for your weight, the other settings will only mask the problem.

Adjustments on the front are nothing. 
I can adjust ride height on the rear.  That's it.  I have the ride height set stock, with the sag being appropriate.  No other adjustment.

So I don't see adjustment as a solution.

Softer at low rates without creating more wallow under cornering loads  Better overall feel.  That would be good, and isn't really a suspension setup thing.  To my understanding.

[John Ulrich]

First thing I change when a bike (motor or pedal) comes home is the seat & suspension.  After that it's all good.

[rtbickel]

Matris makes an adjustable cartridge kit for the front, Ikons or Progressive shocks for the rear.  A bit pricey, but well worth it

[toaster404]

Rear end: Ikons I can afford.  I had a recommendation of Wilbers for $929.  Am really wondering whether they are actually any better in real life moderately laid back use than ikon 7610, which look to have lots of wire wound dual rate.   I could match up something from Progressive, I'm sure: http://www.progressivesuspension.com/pdfs/7100-105.pdf  I found this:  http://www.guzzitech.com/forums/threads/cal-1400-suspension-thread.13359/ but suspect that either intentionally or just from enthusiastic seller bias that it might not be entirely objective. 

Fork:  While the custom etc may use the Tenneco-Marzocchi cartridge fork, I am not sure about the touring model.  Anyone know?  The suggested Matris fork kit is too much money right now.  If the Touring does not have the same fork guts and is simply an old school system, which the ride quality may suggest, then I can work on it. 

[rocker59]

Why isn't the suspension electronically controlled?   

$$$$

But I'm sure it will rear its ugly head soon enough...

[rocker59]

I had a recommendation of Wilbers for $929.  Am really wondering whether they are actually any better in real life moderately laid back use than ikon

In real life moderately laid back use, the stock suspension is perfectly adequate. 

You have an expensive motorcycle. Don't cheap-out on suspension upgrades, if you believe your bike needs them.

[rocker59]

Softer at low rates without creating more wallow under cornering loads  Better overall feel.  That would be good, and isn't really a suspension setup thing.  To my understanding.

If you had shocks with preload, compression damping, and rebound damping adjustments, you could get rid of any wallow you are experiencing during hard corning.

I've been lucky and most of the bikes I've owned over the past 20 years have had adjustable suspension, and none of them wallowed.

[pyoungbl]

DISCLAIMER:  I do not own a 1400 Guzzi

OTOH, I do have some suspension experience based on getting 3-4 other bikes to ride better.  First, there are only a few ways to build shocks.  You have springs and then some kind of dampening system.  The latter comes down to emulsion (least expensive) where the liquid is in direct contact with some gas, frequently nitrogen.  The liquid and gas can get all churned up during spirited use and cause a loss of dampening; next is some method of keeping the gas and liquid apart (gas piston or even rubber bellows); finally a remote gas reservoir that keeps the fluid/gas apart and also allows for cooling.  There will also be some kind of valve system to allow fluid to move in a controlled manner.  Inexpensive shocks might use just a couple holes, more expensive ones tend to use a series of very flexible washers that might be under spring pressure.  The expensive shocks tend to have better/more complex valves.  They are also re-buildable. 

Many OEM shocks have some adjustment for compression dampening.  Usually this is a small screw near the bottom of the shock.  This same adjustment frequently changes the rebound dampening too. High end shocks will have remote adjustment for preload, compression, and dampening.  If you are determined to break the bank Ohlins sells shocks that are adjustable on the fly.  Take a look at a Ducati Multistrada.  You can choose from about 20 different suspension combinations, all done electronically. 

Progressive Suspension has a good book all about suspension.  You can get it from Amazon and it's well worth owning. 
https://www.amazon.com/Techs-Motorcycle-Suspension-Motorbooks-Workshop-ebook/dp/B00FKYXJCM/ref=sr_1_1?s=books&ie=UTF8&qid=1466010412&sr=1-1&keywords=suspension+bible

Personally, I do not like progressive springs.  Most rear suspension has a built in progressive nature.  You will see that the shock moves a smaller distance than the rear axle and the rate changes as the axle moves up.  For the forks the same thing happens...as the forks compress they compress a gas (air) which offers more resistance the more it is compressed.  Using springs that vary their compression would seem to be doubling down on the spring rate.

[toaster404]

I found an aftermarket fork mod set designed to work with the existing cartridge fork guts:  http://www.carpimoto.it/EN/Engine/Motor-Oil/45085_FM109KS-Matris-Fork-Springs-Kit-for-Moto-Guzzi-California-1400.htm  Would be helpful to have:

Stock spring rate: XYZ, This spring rate ABC
Stock length etc. 

Fork oil for this bike is FUCHS TITAN SAF 1091 - I figured this out once and can't seem to come up with a cst on it now.  Fuchs makes  SILKOLENE 02 AND 05 SYNTHETIC RACING FORK FLUID they claim is 7.5 wt.  And apparently many other weights.

Anyway, Silkolene pro RSF 7.5 is 37 cSt.  Motorex 7.5 in the Matris kit is 35.9 cSt.   So I'm figuring that's about what the stock oil is, and that any difference in performance with that front end would be mainly in the spring.  Is this a reasonable view?

On the rear end, I have a difficult time matching the shock, which is about 13 3/8" E/E uncompressed with 4.3" range.  Progressive 444 looks appropriate, but I can't find the range of motion and I am attempting to brainstorm the rate. 

Oh well. 

[pyoungbl]

The Progressive tech site lists quite a few options for the 444 series:
http://www.progressivesuspension.com/pdfs/7100-105.pdf

It looks like the following might be what you are looking for:
444-4243B/C
444-4215B/C
444-4021B/C

You mention 4.3" range.  I guess that is the Guzzi spec for suspension travel.  The shock probably needs less range.  When I did my V7 I calculated the shock travel thusly:
measure center of swingarm to center of rear axle...in mm
measure center of swingarm to center of upper shock mount...in mm
measure center of lower shock mount to center of upper shock mount...in mm
measure distance from lower shock mount to rear axle...in mm

Lay out all these on a large piece of cardboard.  You will have a triangle. 
With a piece of string lay out the arc for the swingarm as the axle moves up and down.  You can then measure up that arc (in this case 4.3") and see exactly how much the shock has compressed.  I'm betting it's much less than 4.3".  Just for grins, please let me know what you determine.

As for the spring rates needed....I don't have a clue but I bet the tech at Progressive can give you a pretty good idea.  You might want to measure the diameter of your OEM spring wire.  Use a micrometer if possible.  That might tell the tech what you have now and adjust from there.  If you already have reasonable sag you might be smart to stick with that.

[stephenm]

I sent a rear shock from my 1400 Touring for testing.
My tech said the spring was suitable for the weight of the bike.
The compression damping was a fixed rate, regardless of how sharp the bumps were.
The setting for the compression damping was too strong for mild bumps, OK for medium
and too harsh for sharp bumps.
The rebound damping was too weak for the bigger bumps, allowing wallowing.

I replaced the Sachs units with Protech emulsion units with springs similar to stock,
compression damping which is not user adjustable but which varies according to
the sharpness of bumps, and rebound damping which is adjustable.

I ride two up most of the time. The bike is now wallow free under all conditions and
more comfortable when touring. The Protechs would be similar to Ikon in price.

Stephen

[toaster404]

I sent a rear shock from my 1400 Touring for testing.
My tech said the spring was suitable for the weight of the bike.
The compression damping was a fixed rate, regardless of how sharp the bumps were.
The setting for the compression damping was too strong for mild bumps, OK for medium
and too harsh for sharp bumps.
The rebound damping was too weak for the bigger bumps, allowing wallowing.

I replaced the Sachs units with Protech emulsion units with springs similar to stock,
compression damping which is not user adjustable but which varies according to
the sharpness of bumps, and rebound damping which is adjustable.

I ride two up most of the time. The bike is now wallow free under all conditions and
more comfortable when touring. The Protechs would be similar to Ikon in price.

Stephen

That is very useful.

I have spoken with Traxxion - they seem to have a very good idea how to proceed.

[Rox]

Ever consider getting it all rebuilt by Racetech?  I did both front and rear full revalve , spring oil and nitro charge for my v11 for about 1400 including labor , parts and set up. Brought the bike in to them in the morning and had it back by close of business. . It's night and day.

It would certainly be cheaper if you sent the parts to them.

[toaster404]

StephenM - that sounds exactly right, and what I need.  Moderate surfaces and speeds, just fine.  Big hard bumps and slow holes are horrible!!!  Would you have a model number for the Protech emulsion units you got, or were they made to spec?

I'll look into Racetech. 

[stephenm]

Looked up my emails...they are 'Promax,' not Protech.

I provided rider, passenger and luggage weights, typical usage etc.
The shocks were assembled to suit.
I fitted a nylon zip tie to a damper rod and went for a series of
rides over my 'test loop' solo, two up and loaded, recording
the shock stroke after each loop, static sag etc, and Walter, by email,
guided my adjustments until I had them dialled in.

Preload is adjusted by threaded collars, which requires removal of
the panniers.

I got them from Walter Preisig at YSS (Your Suspension Shop)
in South Australia.

They cost about US$600 at the time.

Stephen