Fork suspension adjustment

[Lost Californian]

I have never had adjustable suspension before. Well, closest thing I had before was air over hydraulic on the cop bike (KZ1000P) and the Honda Magna, years ago. Just want to make sure I understand all these things right. Tried to put this in the NEPRT forum, but I can't post there yet.

Compression damping (adjustment on the bottom of the fork) - this controls the RATE and which the forks compress. The smaller the orifice (1 click out) the less oil can flow, slowing down everything.

Rebound damping (black adjustment knob on top of fork leg) - this controls the rate at which the forks return to normal. I am lost as to what effect this has on the bike.

Spring preload (nut on top of the forks) - this changes the the length of the fork spring by tightening a bolt thru the spring, making it harder/softer for the spring to start reacting, and it has a side effect of changing the height of the bike. Stiffer spring = stiffer ride/lower front end.

Do I have that all right? If not, could you please educate me....nicely. Or yell at me. Either works.

Thanks, y'all!

 

[fastpappy]

There is a long thread that discusses in depth the suspension and recommended settings by Mr. HaulinAshe our resident suspension and tire testing Guru (we are not worthy). I am not savvy enough to link you but search is your friend.

 

[ER RN]

Here' the link to a Google search My link You can search the forum thru Google just use "FJR forum:and your search term"

 

[Donal]

Click here for all to be revealed

Don

 

[phroenips]

At first glance, HaulinAshe's thread doesn't explain what effect rebound has

The OP is correct that the rebound damping effects the rate at which the suspension expands back out. This is important so that the tire remains in contact with the ground providing maximum traction over bumps, in turns, etc.

If rebound damping is too slow, you can "pack" the forks over rough road where they won't rebound fully enough before the next compression. In this case, the tire can remain in the air while the road drops down, leaving rubber not in contact with the road. Also, you're not utilizing the full range of the suspension and in a worst case scenario, you can bottom out the forks.

If rebound damping is too fast, it will almost feel like the bike is launching up over bumps, and in the extreme, it will lighten the loading of the tire on the road, also resulting in reduced traction.

Here's some more information: https://www.gostar-racing.com/information/motorcycle_suspension_set-up.htm

And also, after you get preload setup, here's a video showing what the suspension should do with proper rebound adjustment:

Forks:

https://www.youtube.com/watch?v=mJV-jhEtjz4&feature=relmfu

Rear shock:

https://www.youtube.com/watch?v=SXDL_jREhEE

 

[Lost Californian]

At first glance, HaulinAshe's thread doesn't explain what effect rebound has

The OP is correct that the rebound damping effects the rate at which the suspension expands back out. This is important so that the tire remains in contact with the ground providing maximum traction over bumps, in turns, etc.

If rebound damping is too slow, you can "pack" the forks over rough road where they won't rebound fully enough before the next compression. In this case, the tire can remain in the air while the road drops down, leaving rubber not in contact with the road. Also, you're not utilizing the full range of the suspension and in a worst case scenario, you can bottom out the forks.

If rebound damping is too fast, it will almost feel like the bike is launching up over bumps, and in the extreme, it will lighten the loading of the tire on the road, also resulting in reduced traction.

Thank you, phroenips. That was the information I was looking for. I had read a whole bunch on HOW and WHERE to set the suspension, but not so much on the WHY bit. That helps a lot. Thanks again.