Please explain suspension basics to me.

[Hank]

I have read quite a bit about various suspensions, but rarely does anyone actually say what the riding difference is.
Does it bounce more? Less?
Is there a difference in cornering?
What is the difference when braking?
Is it just the amount of travel available? Or the ability to change settings?
I am 6'3", 205. I get that the bike is meant for someone shorter and lighter.
But what does that mean in practice?

 

[dduelin]

At the most basic level good suspension allows the wheels to run over bumps and dips without passing forces into the frame and handlebars. This is suspension movement both compliant and damped.

In corners good suspension soaks up bumps/dips without changing the rider's chosen line and it also allows the rider to change line after entry within limits of tires and ground clearance.

Spirited riding may heavy braking coming into a corner. If the bike's compressed forks from braking quickly pop up when the brakes are bled off the steering geometry changes forcing the rider to adjust line or run wide. Good suspension doesn't change chosen line when the brakes are trailed off or even quickly released.

Sometimes an unseen obstacle or change in surface traction in a curve forces the rider to let off the throttle exiting a corner. Good suspension won't collapse and upset the the bike.

 

[Hank]

Thanks, dduelin.

 

[ST13Fred]

I've read the average bike is set up for a 160# rider meaning very few give the perfect ride.
The ideal suspension has the tires following road irregularities well which give the best traction/smooth ride.
Motus with its high end adjustable suspension and light weight forged wheels is a very smooth ride......it is well suspended.

 

[Deleted member 1183]

I suppose there is no simple explanation to encapsulate "how to" with suspension. What is true though is that good replacement suspension makes a significant difference.

I remember some years ago when I owned a Varadero, I decided to update the suspension to an Ohlins Unit with all the bells and whistles. Shortly after I did the upgrade and even before I had the adjustment perfected, I was riding with a friend. We were riding briskly and one section of road included a small sharp humpback bridge that we always attacked with gusto. I launched off the bridge, nothing spectacular with a little air under the wheels, and landed without fuss. My friend was watching behind. When we stopped he noted how the bike landed smoothly and continued on under complete control. We both knew that such a smooth landing never happened with the OEM shock. With that unit in place the bike would have bottomed out and pogoed up the road before coming under control. The difference was immediately obvious both to me and my friend.

On a bike like the NC an aftermarket shock will make a very significant difference. I always get a shock with compression damping adjustment because too much compression damping can hurt and it is good to be able to adjust it to ones liking. Such suspension is expensive though. It is also critical to get the spring rate right. If the spring is too hard you can end up in the same position you started off with. When you get that right it is a matter of adjustment from a base setting, and that can take a little time. I always do it by the seat of the pants feeling. Others are more scientific.

Forks can be dealt with using emulators or replacement cartridges. I believe emulators are excellent when set up properly. I tried some very expensive Andreani Cartridges and never got them right. In the end they were a primary reason why I parted with my NC.

I do not profess to be an expert on suspension but I have some experience and generally get my bikes to handle to the point of comfort and confidence while riding. With new suspension this can take time until one finds a good overall setting to achieve a good feeling over a variety of surfaces. Sometimes a change of setting is required in transition between one type of road and another, such as metalled road and offroad. That is where ESA is an absolute boon but sadly is not available for NC's.

Just some thoughts.

 

[Hank]

Interesting. I am probably not a good enough rider to tell much difference now. It sounds like I should consider an adjustable rear first.

 

[ST13Fred]

In 1984 I bought a new 82 CB900F. On the ride home I was coming down a hill at about 50 MPH where the road made a L/H turn but was wash-boarded just before the turn.
I puckered up pretty badly thinking this may not end well. I'll never forget how well that bike turn those bumps. I was impressed. The tires stuck like glue to the irregularities and was smooth.
Motorcycles have a very small contact patch, are much safer with correct suspension and far less forgiving than a car regarding road grip.

 

[AsureDawn]

In 1984 I bought a new 82 CB900F. On the ride home I was coming down a hill at about 50 MPH where the road made a L/H turn but was wash-boarded just before the turn.
I puckered up pretty badly thinking this may not end well. I'll never forget how well that bike turn those bumps. I was impressed. The tires stuck like glue to the irregularities and was smooth.
Motorcycles have a very small contact patch, are much safer with correct suspension and far less forgiving than a car regarding road grip.

Pretty much how I felt going around a turn a bit fast when I realized there was gravel across the road. Thankfully it wasn't much, and the front and rear tires both only slid a bit through the turn, at about the same rate.

 

[supertux1]

Here's three good reads everyone who rides should be familiar with, even if you're not on a sportbike or interested in track days:

Race Tech's Motorcycle Suspension Bible (Motorbooks Workshop), Paul Thede, Lee Parks, eBook - Amazon.com
Total Control: High Performance Street Riding Techniques, 2nd Edition, Lee Parks, Erik Buell, eBook - Amazon.com
Amazon.com: A Twist of the Wrist II: The Basics of High-Performance Motorcycle Riding eBook: Keith Code, Doug Chandler: Kindle Store

I have the Race Tech Gold Valve cartridge emulators in the front and a Nitron R2 shock in the back. Both sprung for my weight and adjustable. Lots of $$$.

What I notice now is that when the bike 'settles' or compresses the suspension in turns, the geometry is maintained.

When setting up for a turn, I brake to set my speed. This pitches the bike forwards as expected. Then off the brakes, the bike levels out and I begin the turn.
As I lean over, the suspension on both ends compresses at the same rate since they are sprung for the same weight and have similar low speed dampening tuning.

The bike geometry is maintained throughout the turn, the quality suspension does not increase or decrease the amount of trail, so fewer steering inputs are required to hold the line.
The stock shock would compress quite a bit under my 200 pounds + luggage, and if the turn was really aggressive I would have to push the steering more to the inside or risk running wide.
(If I screwed up the entry speed or position, that's another matter entirely and the worlds most expensive suspension and tires won't save me from myself.)

Consequently, I can take turns faster and with more lean angle without fear of losing traction. I can see now why those race guys spend a lot of time and money setting up suspensions!

 

[jjfonvillars]

For the first time in my 40 years of riding bike I have replaced the rear shock, at 12000 kms, and it changes a lot, first I tried to loosen or compress it the but it does'nt change the hard feeling of bumping on dirty roads, dont waste your time, the original rear shock is a bad piece on this bike.

 

[ST13Fred]

Riding on a smooth GA roadway on my new ST1300A I noticed the front suspension was nearly bottomed out feeling 'bouncy' (harsh).
I (am 220#) installed stiffer springs problem solved. An FJR13 owner and I swapped rides in N GA once. He said my ST13 had a 'Fleetwood' feel, soft.
After getting back on my bike it did have a softer feeling front end than the FJR. Also an FJR is more top heavy than an ST13 requiring more effort transitioning turns......OK back to the NC.

 

[DCTFAN]

I have read quite a bit about various suspensions, but rarely does anyone actually say what the riding difference is.
Does it bounce more? Less?
Is there a difference in cornering?
What is the difference when braking?
Is it just the amount of travel available? Or the ability to change settings?
I am 6'3", 205. I get that the bike is meant for someone shorter and lighter.
But what does that mean in practice?

I know something about how it should work and what is the 'best' setting,
but also consider the subject of 'suspension tuning' to be somewhat close to 'black art'.
.

We mostly get text book answers and commentary of how this and that works,
but proof in the pudding is, IMO, experienced individually.
.
As for my ride, stock suspension is fine as seen in the video I took below:
[video=youtube;bG4HTtUqmbM]https://www.youtube.com/watch?v=bG4HTtUqmbM[/video]

 

[dduelin]

I know something about how it should work and what is the 'best' setting,
but also consider the subject of 'suspension tuning' to be somewhat close to 'black art'.
.

We mostly get text book answers and commentary of how this and that works,
but proof in the pudding is, IMO, experienced individually.
.
As for my ride, stock suspension is fine as seen in the video I took below:
[video=youtube;bG4HTtUqmbM]https://www.youtube.com/watch?v=bG4HTtUqmbM[/video]

Also called the Potter Stewart method

 

[happy]

Preload = setting to match the weight of bike + person/s and should match the usage of the bike (motocross or road racing)
Damping = amount of hardness/softness in the shocks to slow/quicken the up/down movement
Travel = amount of up/down allowed
Rebound = how quick/slow the movement should be.

Based on the above 4 general areas and combined with weight and usage of the bike, multiple sets of settings can be set up.

Now I wait to be corrected / updated.
Cheers.