Easy question!! Front fork spring replacement

[tclark2020]

Hey guys, Was wondering if anyone can help with a small dilemma. I just bought new heavier springs for my 1988 kdx 200 and am not sure how to put them in..... They came with the springs and a piece of white pvc pipe the same diameter as the springs and about 8" long. Can anyone tell me how to put them in and what is the pvc pipe for??? Actually its not a question of can anyone tell me because I know I will get a lot of help, so thanks in advance for the help. Also, I am unable to get one of the caps loose on the fork tube, so any help there would be great so I don't damage anything (I tried a socket and it wants to chew up the top). Travis Clark

 

[jaguar]

I've got installation instructions from Freddette I can give you but I need to know your weight first.
You could first heat up the fork tube so that it will expand and make it easier to unscrew the stuck top cap.

 

[Matt90GT]

The PVC pipe is so you can cut it for preload spacers. Read up on any suspension companies website about front fork preload.

To get at them, you first have to support the frame of the bike. Then loosen the top tripple clamp bolts. if you do not, you will not be able to loosen the fork caps. Once those are loose, the caps should come off easily. With a cartridge fork, you will need to push the spring/spacer down to get at the cartridge rod where is screws into the cap. Seperate the cap from the rod, remove the springs. While you are in there, I would highly suggest a fluid flush and change!

 

[capt hookleg]

You should have about 10mm of preload on the fork spring when installed, cut the pvc to the proper length to accomplish this. The pvc goes on top of the spring and make sure that you have a steel washer between the spring and the pvc. To loosen the fork cap, put the fork back in the triple clamp and tighten the bottom clamp, and then us a six sided socket or end wrench to loosen the nut

 

[tclark2020]

I will work on the cap. My weight is 196 lbs. Thanks for all the help so far. Also, can anything be substituted for cartridge fork, or will I need to buy one?? Travis Clark

 

[Matt90GT]

subsitute a cartridge fork? You dont understand things here.

"Cartridge forks have the damping system enclosed in a separate cylinder (cartridge) within the fork tube to minimize the amount of air that can mix into the fork oil. Air mixed in the oil creates foaming which reduces the damping performance of the fork. Depending on the model application, cartridge forks may have a combination of compression/rebound damping adjustment and/or spring preload adjustment.

"

 

[jaguar]

For '89-'92 conventional forks Freddette says to remove the spring and compress the fork and then pour in the oil until it's 4.75 inches down from the top of the fork (for 200 lb riders. 5" for 150 lb riders). He says to mix 5 and 10 wt fork oils together for this.
Then extend the fork and put in the new spring and place the pvc on top of it. Mark the pvc where the top of the fork is. then remove the pvc and mark 1/2" farther down on the pvc and cut it there. That will give you 1/4" of preload.

 

[canyncarvr]

..but he says '88. Not the same as 'H' series kdx bikes for sure...don't know about '89-'92.

Buykawi's diagram for the '89 looks quite like the '88. Maybe jaguar's write up looks good 'cuz he MEANT to say '88-'92?

Note the oem collar length in the '88 (item 92143a on http://www.buykawasaki.com) is listed as 140. MM I presume. For the same preload on your new springs as your old springs (if they are the same LENGTH), that is the length of PVC you'd use.

Jaguar's write-up from FRP looks to be a method that would apply also to the '88...but make sure whatever method you use applies TO YOUR MODEL.

 

[tclark2020]

Ok, got the springs out, and everything seems to be fine. Jaguar, you say to cut the pipe 1/2 " farther down, do you mean make it longer or shorter?? Thanks guys, this is by far the best place for great information. One other thing, do I need a different washer in between the spring and PVC or will the spring seat work? Travis