Fork seals and forks on 1150

[skip]

my forks are pitted and i keep on going through seals. My parts bike has forks in better cond and the seals are not leaking yet. I want to Swap the forks and then install a set of new seals. How difficult is this? Any tips ?How much will this help the handling of my bike as the old seals leaked bad and I know the fork fluid cannot be the correct level.
I have the progressive susp kit in the forks and will change that to the other forks. What would be a good weight fork oil? Any help would be greatly appreaciated as it is freezing in my garage and the less time spent in there the better................skip

[Billy Ricks]

As for the handling it should help quite a bit. It's not a difficult job at all. Just take care to lay the parts out in order and in the correct orientation as you disassemble things. I have an '85 GS700, and though the forks are not the same the internals should be very similar. I could snail mail you a copy of the pages from my shop manual dealing with the job if you want.

One thing you need to be aware of is Suzuki recommends replacing the teflon coated bushings in the front end when rebuilding. There are two sets involved. One set is located at the bottom of the upper tubes and the other set at the top of the outer tubes. Since you have two complete sets to pick from you might find enough good ones to get by with what you have.

Before you start disassembling I would flush both sets of forks with kerosene several times to clean things up. Remove the springs only and fill the forks about halfway with kerosene and pump the forks up and down to clean up the damper tubes then flip the forks upside-down and right side up repeatedly to clean up the rest of the assembly.

One thing that the manual calls for and has been discussed in this forum a few times is a special wrench to remove the damper rods. When I rebuilt mine I didn't have one nor did I bother to adapt anything. I simply removed the socket head bolt from the bottom of the outer tube with an allen wrench and the damper rods came out.

10 weight oil is generally what is called for. PJ-1 makes a fork oil with seal swell in it to help the seals work better. You may try 15 weight if you feel the damping is too light. What you want in the way of damping is for the fork to soak up the bumps and go right back to its original length quickly without any pogo effect. To heavy of an oil will restrict the action of the fork and slow it down, too light will cause the pogo effect.

When you put the tubes back on the bike and tighten things up, start with the axle and work your way up to keep everything aligned.

[skip]

thanks. I got hold of a manual and I guess all my handling troulble can be linked to the bad seals. It used to pogo very bad in the corners. Do you think that was from low oil level or light weight oil or both? If the seals on the parts bike are not leaking now (although they sat for two years) and still hold air (after two years there was 5psi in them) should I skip the seal installation and just install the whole fork assembly?...............Thanks skip

[Billy Ricks]

That would be the best thing to do. Just install your Progressive springs in that front end. Most of the Progressive kits call for no air in the fork. When you are setting the preload you can vary the length of the spacer that you have to use with most of the kits. If you want a firm, aggressive setting shoot for 1" to 1 1/4" of sag. Sag is the difference between the bike on its centerstand with the wheel off the ground and the fork fully extended, and the bike on the ground with your weight on it. Measure the distance between the top of the lower tube and the bottom of the lower triple clamp fully extended. Then take another measurement with the bike on the ground with all of your weight on it. The difference in the two measurements is your sag figure. Adjust it using spacers of different lengths. The spacers can be made out of PVC tubing. Just make sure to use a fender washer close to the same size as the inner diameter of the top tube between the spring and the PVC spacer. I found that a PVC coupler for 3/4 inner diameter PVC is about the right size and is heavier guage than PVC tubing itself.

As for the pogo effect, it could be from not enough oil or too light of an oil. It could also be from just not using enough of your body weight hanging off when cornering. Start with the suggested oil then go from there. If you still feel it is pogoing then go up to the next weight oil. You don't want to go too far in the wrong direction with oil weight. You want the suspension to settle down as quickly as possible to be ready for the next road imperfection.