BMW R1200R R1150R/T F800 K1200R R1100R/T R1250R RnineT Message Board

As most know, I recently upgraded my suspension to fully adjustable from OEM.

I rode it w/o any rebound changes for a day and it was much improved, especially at speed.

Then I added a couple clicks front and rear (20 clicks available) and OMG!! Absolute change of character. Bike felt like it was on rails in the twisties, nothing like I had ever experienced.

Then I added another for a total of 3 for front and rear and while it was even better, something wasn't optimum, so I backed off one click in the front and added another to the rear for a 2 click front and 4 click rear rebound setting.

My reasoning was for a faster acting front and a more plush rear. Appears to be good, but I have a question for the more seasoned among you.

Is this type of setting bias common? I know a different front and rear setting is common, but does one want a more damped rear and a more active front, or is the opposite better?

I can easily try changes as it's a simple thing to turn the adjustment wheels, but I'd like the guidance of those more knowledgeable to make this journey.

Thanks for any information.

Glad to hear your bike is starting to feel like it should.
Maybe Don's write-up can help you get the most out of it:

http://www.eilenberger.net/Suspension/suspension.htm

Joe's suggestion is great, no doubt. After reading Dons tutorial I would personally jump on the bike and go back to folks you bought the shocks from and have them help you set it up. After studying Don's info you will be armed with the knowledge you need to help you make an educated evaluation of what they are doing to your bike. I would think they would have set the thing up WITH you before they sent you home. But I'm kind of nutty that way.

Thanks for the thoughts, but it's set up correctly. It's the next step I'm looking for suggestions on - rebound.

Sag and preload are perfect.

How do you run your bike? more rebound on the front or rear?

Snapping Twig wrote: How do you run your bike? more rebound on the front or rear?

I think the moral of Don's write-up is if it doesn't feel right, you need to spend time getting what feels right for you, there's no magic setting that everyone uses I believe. If your sag and preload are fine then it's up to you to dial in what feels right if they didn't come setup to your liking. I would go back to the base-line factory settings, then follow Don'e instructions below, the important part is only change one thing at a time.
I have a nice course in the canyons I run a lot, after my recent shock rebuild all I needed to do to mine was increase 2 clicks compression in the rear. As long as my tires are fresh my bike feels perfect as is, sorry I can't help more with settings as I have not experimented with mine on the R much. I play with the settings with the WP suspension on my other bike more, but those settings won't help you here.

Good luck!







Suspension setup - final installment (I think..)
Since I covered all the terms, and how to setup your spring preload, I'll try to briefly cover setting the damping on shocks that allow this..

First - you need an afternoon, good weather, plenty of time. You need to check and adjust your tire pressure. Carry the load on the bike you normally carry. And you need a course. I have a loop that I use that has the following features:


Long straight section

Washboard section

Pavement cuts - poorly filled

Light traffic

Safe place to pull over to make adjustments


The loop is about 5 miles in length, and takes me about 8 minutes to do. It has a decent spot to pull off to the side where I can make adjustments without worrying about a car running into me, and it has little traffic usually.

I first start out making 2 loops of my route - just to get the feel of how the suspension now feels and determine what I think could be improved. I'm looking for:


High speed stability in the straight section - I can hit about 70 on the straight section, not terribly fast, but fast enough to feel if the bike feels "stable" and "planted" at speed

Comfortable ride - the washboard section and the pavement cut (badly filled - nice sharp edges about 2' apart) will tell me if the suspension is compliant. The washboard will tell me if the rebound damping is too high and "packing down", the sharp edges will tell me if the compression damping (especially on shocks with two compression adjustments - the high-speed adjustment) is correct.

The twisties section tells me if the control feels good - and control is really changed with rebound damping on twisties. Too much rebound and the bike feels wooden and starts to compress and run wide (rake increases), too little and the bike will have an unsettled feeling - not-planted feeling. Too much low-speed compression damping will result in the suspension jacking up, and the bike turning in quicker - again - not-planted feeling.


What do I do to make the adjustments?

IMPORTANT - only adjust one thing at a time. ONE THING. Making more than one adjustment will lead to rampant confusion, I know, I've done it.

First a note on how to make any adjustment:

Start out with a large adjustment so you can FEEL the effect the adjustment has. On compression adjustments, I usually turn the adjuster 3 or 4 clicks higher, which should make a very noticeable difference in feel. Once I make the adjustment, I circle the loop, as many times as needed to be sure I feel exactly what the adjustment did.

IF the adjustment made things feel better (in this case - high-speed compression might make the sharp edge of the pavement cutout feel less sharp) - then I continue making adjustments on that adjuster until things feel worse - and I make smaller (1-2 clicks) adjustments. Once the adjustment starts feeling worse - reverse direction and work back toward where it felt better. Continue in that direction until it feels worse - then reverse again and narrow it down to the single click position that feels "best"..

If your initial big adjustment immediately made it feel worse - go back to where you started - and go for a big adjustment in the other direction. Then work your way in to where it feels best.

Doing ONE adjustment at a time will teach you what adjustments change what feeling in the bike..

In general:

High speed compression - changes sharp shock response, the badly patched pavement-cut with a sharp edge. Too much will shock you, too little feels unstable.

Low speed compression - does the bike feel "planted" - especially in curves? If not - increase low speed compression until it does. Too much low speed compression can make the bike start to hike-up, with the rear suspension jacking upward over undulating pavement, or a series of curves. In that case the bike will start to turn sharper into turns as the rake on the front end is decreased by the rising rear suspension.

Rebound - the washboard section is usually good to adjust this - if the bike seems to "pack down" - compress the rear suspension over the washboard, it will become harsher as you travel through the washboard, it will also become slower to respond on curves (tend to run wide) since the rake is increasing with the lowered rear suspension. Rebound also can cause sharp impacts to feel harsher if the wheel isn't recovering (rebounding) fast enough due to too much rebound. Too little rebound can give a pogo sort of feeling, especially in the twisties section as the suspension loads and unloads.

That's the basics - and using a course, giving yourself plenty of time will give you a chance to learn how the adjustments change the bike. The adjustments DO interact to some degree.. you may find adding more rebound might mean you also need a bit less compression damping..

It's sorta fun to do if you attack it as a puzzle, and do it very methodically. Make ONE adjustment at a time is the biggest rule! Doing otherwise will lead to brain-fog. BTDT.

That's it folks.. if there are any comments or questions - feel free to email me!

Snapping Twig wrote:Thanks for the thoughts, but it's set up correctly. It's the next step I'm looking for suggestions on - rebound.

Sag and preload are perfect.

How do you know "Sag and preload are perfect"? Perfect for what? Based on what? Measurements are a start, but even the suggested dynamic sag setting as a proportion of travel changes depending on who you're talking to (and that is just the starting point for that adjustment..)

I tend to change my suspension settings depending on what I have on the bike as far as gear (luggage, bags, whatever) and even the type of riding I expect to do.. More weight requires more damping (and less = less.)

If I want to do a lot of tight twisties, I want a faster turn-in, and that means either raising the rear of the bike a smidge (easy to do with a remote hydraulic preload adjuster,) or lowering the front (not so easy to do - so I almost never change the front preload, especially since weight tends to get loaded on the rear.)

For a long highway tour, especially with truck wind-gusts, I want more stability going straight.. I may lower the rear suspension just a tiny bit. Once attuned to the change, the effect is VERY evident (actually went to the cheap cigar store today, and took the seat off on the street to change the rear preload from what I had it set to for the loaded up Canada trip.. It made a very nice difference. Once I reload - probably tomorrow, I'll put the preload back up.)

Don't take someone's word that they are "perfect" - just because they were measured. As I tried to point out in my writeup, (and Joe noted) there are NO hard and fast rules to setting up suspension.

Doing it right takes skill, knowledge and TIME RIDING THE BIKE to set it up correctly, and even then - what one person loves, another person may hate. If the person doing the setup didn't spend an hour or more riding and adjusting the shocks, they were not setup, and if the rider/adjuster was not the same weight as you are, chances are good they aren't correctly setup for you.

Dunno if you ever pit-crewed for any racers - Tom Cutter (a very well regarded WERA senior rider) is known to change suspension settings many times in practice laps setting up for a race.. and if the track conditions change, he's back to adjusting them. It really does make a difference.

How do you run your bike? more rebound on the front or rear?

I have no idea what you mean by that question.

What do you mean by "more rebound"? How are you measuring it?

The front shock and rear shocks are different. Different designs, different springs, different loads, different travel, etc. Using the same number of rebound clicks on the adjuster on each will NOT equal the same effect on the suspension. One size/adjustment does not fit all. That's why I suggest making ONE adjustment at a time, and seeing what the effect is. Make a small adjustment each time, then ride it until you can TELL what changed and if you like it better or not. If better - try even further with that adjustment until you stop feeling "better".

I think you might benefit by reading up a bit on suspension 101.. Wilbers used to have an excellent book on suspension setup. Expensive, but worth it. It went into the details needed to understand what the adjustments should achieve, and without that knowledge you'll be quite frustrated just tweaking things randomly.

Suggested book purchases:
http://www.wilbers.de/en/infomaterial.php
http://www.bikeland.org/story.php?storyID=56152
http://www.asr.com.au/motorcycle-suspen ... etail.html