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Re: Shocks and Springs (longish)
- Subject: Re: Shocks and Springs (longish)
- From: Gregory Appling <gappling@xxxxxxxxxxxxxx>
- Date: Fri, 10 Feb 2006 09:40:37 -0800
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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