KX500 too TALL!!!

[kawdude]

All,
I'm contemplating how to lower the seat height on my 94 k5.  Basically, I'm too short for the bike but in no way do I want to switch to something else.  I've lower the forks in the clamps about an inch but what can be done with the rear?

Thanks!

[DrMojo]

Wow, one inch on your front forks That is a huge move.  I moved my tripple-tree down 1/4 inch and this really changed the bike's dynamics.  Normal setting for the shock tubes is nearly flush with the tops of the tree.  

I am 5'7" - 160lbs (see my pics on the bike's fit) and once I set the rear sag properly, the bike fit very well.  When I got the bike the shock was set for a much heavier rider (typical).  I had zero sag and the bike felt ten feet tall.  

Once the "sag factor" was dialed in, I can sit on the bike with the tips of my toes touching the ground.  This is near an ideal fit.  Starting the bike is not a problem either.  I have raced a few very technical Hare scrambles and big KX is a nice mount for someone my size.....not too big and not too smal.......just right (for the mildly insane)

So before you make radical shock link and fork tube changes, keep to basics and adjust the sag first.  There are a few very good posts on this site from, Rick I believe, that cover sag adjustment.

Good luck.

[rhinogrrrl]

I know all too well about not touching the ground! I need some extra rubber on my soles to make them higher...MX high-riser boots.   That way i won't be constantly doing the 'side to side' dance whenever I stop.  

Definitely set the sag first before doing anything radical. Those K5 seats are pretty plush...you could shave it down a bit?  

[teamgreen500]

You can shorten the sub-frame. This means you've got to relocate just about all the mounting tabs; Air box, side-panels , silencer...etc.;However, it can be done!

I believe Wardy and a few others had this mod on their MX Nat's bikes. Remember-'89-'91 KDX and '88(250-500) and all '89 sub-frames work. The KDX sub's also have tabs for an over-flow bottle which can be used for extra gas.

Another trick, using adjustable/different size "Link Rods" adjusts the ride height...but, the suspension curve also.

Best of luck,

Manny

[Rick]

Manny hit the nail on the head (assuming that the sag is properly set with the right spring for your weight).  The pull rods are pretty easy to make if you have access to a mill or a GOOD drill press with a milling vise.  I have used aluminum bar stock before, and while I don't have the brass inserts in the holes, or the fancy writing on the side, I have never had a problem with making my own pull rods.  The most important thing is that the holes must be in PERFECT alignment with one another.  The simple way is to weld the two pieces of bar stock together, drill the holes, then finish the pieces as a set, with the last step being removing the welds (If you can weld aluminum, or have a friend with that tallent and equipment).  A more difficult solution is the drill the first hole, bolt them together, drill the second hole, add another bolt, and finish the two pieces as a unit. Not as exact, but if you are carefull, it will work.

As I mentioned, I have made several sets of pull rods for my vertically challenged friends, all without any problems (except that one guy who forgot to tighten the bottom shock bolt, and when it backed out, it cut one of the pull rods in two   )

As a note, one of the local Kawi dealers sent an new KX500 owner my direction, as he was unable to get his suspension working.  It turned out the guy only weighed 135 pounds.  As one would expect, the 5.6 rear spring was a little    too big.  Since I have a few extra rear springs, we set the bike up with a 4.9 rear spring (yes folks, that's a 4.9 off a kx250), that brought his rear sag to 7/8 inch static at 4 inch race.  Just perfect.  He no longer rides while doing a hand stand on the bars.  Also, he can't be much more than 5'4", and with the right spring, has no interest in lowering the rear of the bike at all.

Good luck

Rick

[teamgreen500]

Thanks Rick! Great Idea!  You can locate the two pieces with a square/rectangular dowel and that might help with those who don't have the welder/equip handy. You can use shims to get them nice and straight.

Also, you can make your own brass bushings from brass rod stock. I'd drill a hole about.020-.030 small and ream to size. You'll have to make them for a press fit into the rods. You'll probably want to ream after pressing into place. Use the stockers as a guide to material sizing.

BTW, I'll be checking with you on this in the near future Rick. I want to make some Carbon-fiber rods and I'll talk to you about geometry/set-up.

Great thread! Have you put a KDX Sub on your kids bike? Extra gas for those "Long-runs"!

Manny

[kawdude]

All,
Thank you for all the excellent suggestions and information.  I will start with setting the sag correctly and "readjusting" the height of the front forks so that the bikes dynamics are not so screwed up.  If anyone has any other suggestions please let me know...

[NVR-FNSH]

Shave the seat foam.  And I just happen to have a couple of extra seat foams I looking to sell:)  One stock height, one 'tall' - both are from CEET.

Brian

[Adam]

I bought a KX 500 low profile seat from the factory, and i purchased a set of Koubalink dog bones. These two items lowered the bike about 1". This was expensive, but it worked well because the bike tracks better with the new linkage. I also lowered the fork tubes about 10mm.


Good luck, Adam