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Re: Shocks and Springs (longish)



Thanks everyone for your suggestions.

I had my bike set up by a track junkie so after reading this 
particular e-mail I kind of figured out what was happening. My bike 
is set up for twisties so my everyday commute ride seems a little 
off. After thinking about what it was like before I had it adjusted I 
backed off the pre-load three clicks and my bike seems to be a lot better.

I probably need to figure out what the majority of my riding will be 
and set the bike up that way.


Thanks alot everyone for the advice.

gregory

PS: Marc, Can't make the event on Saturday see you at the breakfast 
ride on Sunday


At 12:07 PM 2/9/2006, you wrote:
>Gregory:
>
>In my experience, there are approximately three kinds of riders:
>
>The first is what I'll call the basic rider, (full touring and 
>cruiser riders sometimes fit into this catagory too) He or she rides 
>a motorcycle on the same roads and at the same speeds as a family 
>car, takes the interstate if he wants to go somewhere and doesn't 
>ride much over the limit unless he's riding in a straight 
>line.   This is the type of rider is always trying to get the last 
>mile out of his tires and doesn't really understand what the deal is 
>with shocks.   Some of these riders are high mileage guys, some are 
>just occasional riders.  Most Harley and Cruiser riders fit into 
>this catagory because ground clearance is so limited on this type of bike.
>
>Second is the BMW (And other Euro and some Japanese bike) 
>Touring/Sport Touring sort of rider.   This is the guy who takes a 
>lot of back roads, enjoys a road with good, tight, curvy "technical" 
>sections.  He may pack a weeks worth of gear on his bike, he may 
>camp, he may not.  He appreciates great handling on his bike and 
>knows what a bike feels like with a working suspension and good tires.
>
>Third is the racer/Track Day junkie.   This guy is looking for lap 
>times, brake points, apexes and lean angles.  His bike may be 
>trailered to the track and used for that purpose only.   He's not 
>concerned about road-worthy comfort because he's not riding very 
>far.  He changes tires often, uses low track inflation pressures and 
>makes a science out of setting up his bike.
>
>The seminar recommended on the link in the last digest seems to be 
>oriented toward the third type of rider.
>
>I have done track schools and even have a sport bike, but I'm 
>definitely in the second group as far as the riding I do the most 
>and like the most. I've talked with a lot of guys in the #3 catagory 
>and I don't generally agree with them about suspensions and how to 
>set them because I'm looking for a different sort of balance between 
>ride and road dynamics than they are, so take what I say with a grain of salt.
>
>If you are a #1 rider, chances are that you won't really care much 
>one way or the other about your shocks.   If you're happy with your 
>bike the way it is, don't spend any more money on it.  Just ride.
>
>If you have a BMW Oilhead suspension with more than 30K miles, 
>you  ought to have a look at the rear shock damping 
>setting.  Chances are, you're getting almost zero rebound 
>damping.   Look on the bottom of the rear shock on the right side of 
>the bike.   There is an adjustment screw there.  Clockwise is more 
>damping, CCW is less.   Turn this screw clockwise until it's snug. 
>Don't overtighten.   Ride your bike around.   Does it feel 
>better?   Is it harsh?
>
>If it feels better, as in more controlled, you've got some rebound 
>damping left and it's not so much that it's overpowering the 
>spring.  That's good.
>
>If the ride suddenly gets very bumpy, try increasing the rear spring 
>preload one full turn and see if things get a little better.  If you 
>notice improvement, keep tightening in increments until something 
>bad happens, then back off half a turn.   This is probably as good 
>as it's gonna get for you without buying new shocks.
>
>The front end is not adjustable on RTs or Rs.  I think you can 
>adjust the GS front end rebound damping, but I'm not sure.
>
>Some symptoms I've had of really bad shocks are harshness on bumps, 
>a feeling that the bike is out of control on bumps, especially in 
>turns and finally, the bike seems to sort of porpose up and down in 
>the back when you hit a dip.   Kind of like an old Buick, if you 
>know what I mean.  Many people own old Buicks and are perfectly 
>happy with the 130,000 mile shocks on them that were too soft when 
>they were new.   I say, let them drive slow and be happy with their 
>motion sickness.   I am not among them.
>
>When I bought my set of Ohlins, I noticed 1. That the ride was more 
>plush. The bike floated over small bumps.  It was never harsh even 
>over bigger bumps.   I used to count on getting at least one 
>compression "zing" in my back on every ride in spite of my efforts 
>to find expansion joints and stand up a little on the bike when I 
>ran over them...I'd always miss a bad one and get that dull aching 
>pain once or twice.   With the Ohlins, I could sit straight up on 
>the bike (an RT) over almost any bump without getting this. 2. The 
>tires stayed connected to the road better.   If I hit some little 
>bumps on a curve, the bike didn't move around.   After I became 
>accustomed to this new benefit, I found I was much more confident in 
>the curves.   I could keep my eye on the line and just go without 
>worrying so much about every little pavement undulation.   3.  The 
>rear of the bike would compress once and recover from a big dip in 
>the road.  It never porposed up and down...like the above mentioned old Buick.
>
>I've since changed from an 1100RT to and 1150, which has a 
>completely different suspension setup.   I found an Ohlins tech that 
>was able to order up some parts and convert my shocks/springs to the 
>1150 spec.   This was great as it saved me a lot of money and hassle 
>selling and then buying new ones.   Now I have a 1200RT...different 
>setup again.   I was not able to upgrade the Ohlins this time, so I 
>sold them.   I now have a set of Wilbers for the 1200.  This time, I 
>got the full setup with high and low speed compression damping and 
>ride height adjustment.   I'm very happy with the Wilbers although 
>it took me a while to get them set the way I like them.
>
>Being a rider who does long distance as well as back road carving on 
>many sorts of road surfaces, I found that the Sport Touring settings 
>that came with my Wilbers shocks were too strongly damped for 
>me.   I started by leaving the front at the stock settings and 
>setting the rear spring so it sagged about 2 inches or a little less 
>from full extension with me on the bike.  Then, I rode it with the 
>suspension fully soft, then I stiffened the rebound just enough to 
>take the porposing out of the ride.  I worked on the compression 
>damping last.  I moved both the low and high speed compression 
>screws together at first, just increasing two clicks at a time until 
>the ride started to feel stiff and backing it off two clicks from 
>there. Then, I went back to the rebound damping and tweaked it a 
>little more...one or two clicks.   I want the softest ride I can get 
>without chassis control. That's what I like best for a BMW.
>
>I rode it that way for quite a while, making spring adjustment and 
>maybe a two clicks of rebound adjustment only, for a loaded 
>bike.  One day I got tired of the front feeling so much stiffer than 
>the rear, so I backed off the rebound damping about 3 clicks and the 
>bike was transformed.  It now feels like the front and rear of the 
>bike work together.  It's very comfy and it has all the control I need.
>
>I then worked on increasing the low speed compression a bit more 
>than the high speed.  This gives the bike less squat on aceleration, 
>but it also deteriorates the ride a little bit.  More than 4 clicks 
>difference is probably a waste.  In fact, I think both are now 
>within 2 clicks of each other.   It's perfect for me.
>
>The trick is to remember the goal of keeping the bike as soft as 
>possible with controlled ride motions.   Always start with the 
>spring preload and get that set right first.   Next do the rebound, 
>next the compression.  Then look at the preload again and possibly 
>back it down a click or two...no more.
>
>There's an obvious point on each damping adjustment where the ride 
>starts to cross the line into "firm" as you increase damping.  When 
>you hit that, just back off a bit.
>
>Another interesting thing is that the spring rate affects how the 
>damping works.   A lot of people think tightening down on the spring 
>always makes the ride stiffer, but sometimes just the opposite happens.
>
>The most uncomfortable ride is when you have more shock damping than 
>spring strength.  If the ride feels harsh and you don't have a 
>damping adjustment, try tightening the spring preload a little and 
>see if the ride gets better or worse.   If rebound damping is too 
>strong, the supension hits a bump and compresses, the compression 
>damping doesn't allow it to recover.  You hit another series of 
>bumps and the suspension compresses a little more each time and each 
>time doesn't fully recover.   Pretty soon the suspension is riding 
>on the bottom of the stroke and you get VERY uncomfortable.  Tighten 
>the spring in this situation and the recovery is faster and the bike 
>will ride in the center of the suspension's travel where it's supposed to be.
>
>>My bike is a 2002 R1150R with 31K on it.
>
>>I've heard and read in different places that the factor shocks and
>>springs wear out around 30K. What would be the signs that your shocks
>>and springs are starting to go bad and need to be replaced?
>
>My '99 RT's shocks were shagged at about that mileage.   I think I 
>suffered for another 10K miles or so.  The bike wasn't horrible, 
>really.  I'd never ridden a bike with really great shocks on it, so 
>I didn't know what I was missing.  When I put on the Ohlins, well, 
>it's a whole different thing...better than new.
>
>If your bike isn't turning in correctly, it's more likely that 
>you've put too many straight-line miles on the tires, both front and 
>rear, but especially the rear, and they have changed shape.   The 
>rear, because it has to deal with engine torque against the street 
>as the bike moves down the road, is the most vulnerable.  The tire 
>gets flat in the middle with near square corners on the sides 
>instead of a smooth radius to the sidewalls. The front does the 
>braking, so front tires can get the same problem, but fronts usually 
>last longer unless you do a lot of stop and go.  When you ride 
>straight with squared off tires, you can let go of the handlebars 
>and the bike stays straight...kind of fun, really.   Lean the bike, 
>however, and it resists until you get over this sharp corner on the 
>edge of the tires, then the bike seems to fall into the turn.   When 
>you turn with these tires, you're either riding "uphill" onto the 
>square corner, on the square corner, which can be a very small 
>contact patch or "downhill" off the square corner, where the bike 
>feels like it's falling into the turn.  Handling is weird in any of 
>these scenarios and fighting it becomes a nuisance.
>
>Your bike can still be turned and the tires are still safe for most 
>things, but handling is a lot less intuitive and more of a 
>chore.  I've found that Metzler's have stiffer sidewalls than 
>Bridgestones and they are more disagreeable when they get this 
>squared condition.  Although Metz Z6s are about the stickiest and 
>best tires around for riding hard in the twisties, when they get 
>squared off on the interstates, they really don't work the same at 
>all.   Getting new shocks will not fix this.   Just get some new tires.
>
>If you're not ready for new tires, lowering air pressure down to 
>what BMW recommends helps the situation sometimes.
>
>For what it's worth,
>
>-TB


Gregory L Appling
Business Manager
Wetlands and Water Resources, Inc.
1010 B Street, Suite 425, San Rafael, CA  94901
(415) 457-0250 phone; (415) 457-0260 fax
gregory@xxxxxxxxxxxxxx    http://www.swampthing.org

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