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Front fork height on GL1500

This is complicated, please read the whole description.

91 gl1500. Daytona 2+2 car, ez steer.
This is new to me rig. Fixing leaking fork seal leaks which affected the braking and found that the front fork with no rider had almost 2 3/8 of sag.
The front fork springs were sacked providing hardly enough oomph to over come the stiction of the bushings etc. Push it down almost none or slight return.
I decided to upgrade to racetech springs and emulators which I use in most of our bikes because of the dirt road we travel to get home.
They are on their way.

Also I am removing the motorcycle tire and putting on a car tire which will drop the back of the bike about 1".

Now the questions. Right now this rig handles great. It is low to the ground in the front and never lifts under ordinary circumstances
(100lbs of ballast if empty or passenger) in right handers.

When I install the front fork springs and parts I can lower the front of the bike to where it is now by adding a longer top out spring on the damper rod before reinstalling it. The front fork will then sit almost as low as it does right now but it will work much better with the proper springs in it.
The car tire will still lower the back of the bike about an inch. This will change the angle of the ez steer trees a little and I am not sure how much that will affect
the effort to steer the bike. It will lower the center of gravity of the rig and should make it even less tippy than it is. Might steer a little harder? due to the change in rake angle??

Or I can bring not lower the front which will raise the fork about an inch or slightly more from where it is now. The car tire will still lower the back about an inch changing the rake noticeably. I have absolutely no idea what affect that has on the amount of pressure needed to steer the rig. This will also raise the center of gravity of the rig slightly I believe but I am not completely sure.

About us. Both of us drive. On our other rig which is a California 1 with a 88 HD evo tug we had to install Liberty trees because it was too hard to steer without them. Were old and our shoulders show it.

There are many other things to address while this bike has all the body panels off. It's got some miles on it and it is time for some maintenance. Doing the fork twice is almost more than I want to consider. Getting that right the first time would be great. They cover it up pretty good with all that plastic.

I understand the theory of raked trees like the Liberty and EZ steer. I am unsure how much the change in rake of the fork angle by raising the front 1" or slightly more, while lowering the back 1" actually affects the amount of force to steer a wing with a car. I also am having a bit of a problem trying to picture how these two scenarios will affect the center of gravity of the rig if at all. I don't want to make it noticeably less stable in right handers. Let me know what you think about how the two different setups will affect the handling and steering pressure required on the rig if you will.

Thanks in advance,
Joe

I would go with keeping the front lower, when you drop the back with the car tire it will increase you trail, not sure if you would notice it with the easysteer but it doesn't take much to change the ride

I am running double dark side on my 97 1500. after some trial and error and asking questions as well as reading all I could about rake and trail, I found that it handles best when I pump the rear shocks as high as they will go about 100 psi. I also installed progressive springs in my front and run no air
then I raised my fork tubes up about 1" in the trees to lower the front and shorten my trail. I found this made the turning much easier with no adverse effect at higher speeds
I don't have easy steer on mine. I did just add a steering damper and that took all the head shake out.

USCA # 8913

Thanks,
I had completely forgotten that I could raise the tubes in the fork this this bike. I'll have to see if the tubes still clear all the plastic with the ez steer. That would make it easier to lower again without
taking the fork apart. I am not sure how much the front fork will sag with the new springs and the car. I am going to try to measure every thing related to the alignment before I take it apart. That way if it handles worse after the changes I can move it closer to what it was before. I live on a washboard dirt road and it is really bad this year. Having the fork springs sacked and no fork travel because of it just wasn't working. Too tough on the car and plastic on the bike no matter how slow you drove.

fastjoe - 8/7/2015 12:28 PM
I understand the theory of raked trees like the Liberty and EZ steer. I am unsure how much the change in rake of the fork angle by raising the front 1" or slightly more,

I think you are wrong. Raked trees lower front end. At least it did on my bike. Make sure you check alignment of whole rig. I made mistake and did not do it after raked tree install and end up with rear tire eaten up in 500 miles.

I've raised the front forks with modified trees to level some bikes and not done so on others. I haven't noticed any significant difference in handling or tire wear either way.

Lonnie

VLAD - 8/11/2015 10:47 AM

fastjoe - 8/7/2015 12:28 PM
I understand the theory of raked trees like the Liberty and EZ steer. I am unsure how much the change in rake of the fork angle by raising the front 1" or slightly more,

I think you are wrong. Raked trees lower front end. At least it did on my bike. Make sure you check alignment of whole rig. I made mistake and did not do it after raked tree install and end up with rear tire eaten up in 500 miles.

Could be. I will definitely check everything before I start and after I am done.
It handles good right now so I would like to record where the alignment is now and try to duplicate it once the bike is in it's final heights.
I am not sure what to do about the tilt control so that I get apples and apples measurements but I think I saw something about where to set it in the directions.
I'll look at them again before I start. Thanks for the heads up.

Hack'n - 8/11/2015 1:01 PM

I've raised the front forks with modified trees to level some bikes and not done so on others. I haven't noticed any significant difference in handling or tire wear either way.

Lonnie

Good to hear. I am hoping that changing the rake a little doesn't affect the trail enough to make it steer hard. That would be bad.

I think as far as the tilt goes, if I understood what I was told you lower it almost or all the way down until the car is level and then you check everything. I am very happy with my setup but I'm going to be rechecking all my measurements again soon and plan on marking my actuator when I lower it to level the car, that way I can set it there every time and it be the same every time I need to check something if I make a change

USCA # 8913

I align with the actuator at the lowest position. No guesswork later, that way.

Lonnie