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Rear shock pre load

6.6K views 23 replies 10 participants last post by  rcoolbaugh  
#1 ·
Wife and I were going for a lunch ride today. I did my pre-flight and cranked the pre load on the Ohlins up all the way and then backed off about 5 turns. We got mounted and I noticed that the bike was tilted to the right (on the center stand). Strange, never had this happen before, but I don't believe that I ever cranked the pre load up that far. Next thing was that I had a very difficult time getting the bike off the center stand. Finally accomplished that and we took off. The shock action felt fine but maybe a little stiff.

Pulled into a gas pump, put the bike on the side stand and it went way over to the left, I mean way over. Gretchen stayed on the bike while I fueled. I remounted and found that I could not get the bike up right off the side stand. Just couldn't do it :( I finally got Gretchen to lean over to the right side and I managed to get the bike vertical. In the process of all this, I strained both hips and was in pain so we went back home.

I never paid a lot of attention to the pre load before. I am assuming the it must have raised the frame considerably :confused: . Any words of experience will be appreciated. Is there a figure for how many turns on the pre load related to how much height increase. I cranked it down before backing into the garage and that seemed OK.
 
#2 ·
Having Wilbers and just having to RE-SPRING at last rebuild due to what I was told TOO SOFT of spring rate for riding two up.
My best guess would be the radical difference being you too are sprung to soft as well.
Cranking down the preloader certainly will firm up the ride and change ride height a tad, but if your getting massive ride heigth changes your shocks sagging too much in the first place.

JMO ...

What I found with the higher ride height bike go's on and off the center stand far easier !!
But does lean over much further when using side stand. ( For that I carry a small piece of 1X4 in coat pocket )

Boatzo said:
Wife and I were going for a lunch ride today. I did my pre-flight and cranked the pre load on the Ohlins up all the way and then backed off about 5 turns. We got mounted and I noticed that the bike was tilted to the right (on the center stand). Strange, never had this happen before, but I don't believe that I ever cranked the pre load up that far. Next thing was that I had a very difficult time getting the bike off the center stand. Finally accomplished that and we took off. The shock action felt fine but maybe a little stiff.

Pulled into a gas pump, put the bike on the side stand and it went way over to the left, I mean way over. Gretchen stayed on the bike while I fueled. I remounted and found that I could not get the bike up right off the side stand. Just couldn't do it :( I finally got Gretchen to lean over to the right side and I managed to get the bike vertical. In the process of all this, I strained both hips and was in pain so we went back home.

I never paid a lot of attention to the pre load before. I am assuming the it must have raised the frame considerably :confused: . Any words of experience will be appreciated. Is there a figure for how many turns on the pre load related to how much height increase. I cranked it down before backing into the garage and that seemed OK.
 
#3 ·
Hi Bill, there must be something else wrong. Even if you increase the pre load of your shock all the way down there should be no difference in hight of the Bike. Your shock is going harder, is not that soft anymore. Is a very small amount of oil what you pump in to the shock if you turn it down.

Manfred
 
#4 ·
mreuter said:
Hi Bill, there must be something else wrong. Even if you increase the pre load of your shock all the way down there should be no difference in hight of the Bike. Your shock is going harder, is not that soft anymore. Is a very small amount of oil what you pump in to the shock if you turn it down.

Manfred
You're not putting oil into the shock - your putting it into the spring pre-load which does change the height quite a bit.
 
#5 ·
My pre load does change the height of the rear of the bike. In fact I use it to adust the height. When my Gretchen is on the back and I'm sitting on the bike holding it up. I put the kickstand down if it just clears the ground that's about where I want it. If I put it up too high the bike catches the cross winds more. Too low I scrape in the curves. Mine are Wilbers.
 
#6 ·
The whole purpose of an adjustable pre load on a shock is to allow you to place the static (you and pillion on the bike but not moving) loaded bike in the center of suspension travel. If you have a heavily loaded bike and light pre load the shock will bottom out. Like wise if you have a lightly loaded bike and heavy pre load the ride will be stiff since you are at the top of the suspention travel. How much you need to adjust depends on the original spring rate that was installed.
 
#7 ·
Thanks all for the input. I am backing off on the pre load to get the height manageable. I didn't realize it had so much effect on height.

Michael, I am going to try your method using the side stand. (so you have a Gretchen too, great aren't they :D )

My big concern/question still is, why the bike was tilting to the right on the center stand with the pre load cranked all the way down (hard)/ Seems like something is not aligned correctly.

I am also going to take a gander at Ohlins web site to see if I can learn more about the set up on the shocks. I understand SAG, but don't know what to do about it.
 
#8 ·
Boatzo said:
My big concern/question still is, why the bike was tilting to the right on the center stand with the pre load cranked all the way down (hard)/ Seems like something is not aligned correctly.
You are correct, the shock preload should have no influence on how the centerstand functions other than how easy/difficult it is to raise the bike onto the centerstand.
 
#9 ·
Well, it is not the function of the center stand I am alluding to, it just happened that being on the center stand with the pre load cranked all the way down, the bike was tilted to the right as I was sitting on it .

With the pre load eased off, the bike is level on the center stand. Tells me somethin aint kosher? Nothing is moving around the center stand connections so I dunno :confused:
 
#12 ·
Thanks Loren, I always know I can depend on you for help and great advice, wish we didn't live on opposite coasts. ;)

Dave, I know that I am somewhat unbalanced, but not that far :D

I found some good info on Ohlins' site. I need to do some inspecting and first make sure nothing is loose or broken. Then study the manual more in-depth. One thing I learned is to shine the head light on the wall, mark the spot and then load the bike and adjust the shock to get to the same spot. If I am going to do a complete set up, front and back, that will have to wait for winter.

Thanks again to all. :cool:
 
#13 ·
Boatzo said:
Well, it is not the function of the center stand I am alluding to, it just happened that being on the center stand with the pre load cranked all the way down, the bike was tilted to the right as I was sitting on it .

With the pre load eased off, the bike is level on the center stand. Tells me somethin aint kosher? Nothing is moving around the center stand connections so I dunno :confused:
Do you mean side stand or center stand? On the center stand the rear wheel should be off the ground. On the side stand with the preload all the way loose the rear will sit lower and cause the bike to sit more upright. With the preload at max the rear will sit higher and the bike will lean more to the left. That would be normal. Is the rear wheel touching down on the center stand with the preload at max?
 
#14 ·
On the CENTER STAND with the rear wheel off the ground with the pre load cranked all the way down, I mount the bike and it is leaning to the RIGHT . With the pre load relaxed the bike does not have that tilt to the right on the center stand.
 
#16 ·
Boatzo said:
On the CENTER STAND with the rear wheel off the ground with the pre load cranked all the way down, I mount the bike and it is leaning to the RIGHT . With the pre load relaxed the bike does not have that tilt to the right on the center stand.
I don't see how the preload can effect the center stand while the rear wheel is off the ground ie center stand deployed and the bike resting on the front tire and the center stand legs. Something doesn't sound right. :confused:
 
#17 ·
Right Michael, somfin aint right. The rear wheel was off the ground same as always when on the CS. The seat was much higher than usual and sitting on the seat, the bike was tilted to the right. Very strange in deed, that is what is worrying me.
 
#19 ·
John, Yes I did fold down the PL knob. I'll try to get some pics.
 
#22 ·
Hi Craig,

I had that happen early in the year. I now have a centerstand beefed up with gussets. I inspected the C/S and all is well. Again, keep in mind the right tilt only happened when the pre load was cranked to the max. With the P/L eased off all is normal on the bike. It has been too hot here to do anything right now, but as soon as it cools a bit, I am going to get into it. I now know a lot more than I did before this happened so that will help.
 
#23 ·
If it's leaning to the right maybe you need to watch a little less Fox News