Budget front suspension mods

[BigBore]

My nephew has a '93 KDX200. The rear suspension works fine, but the front suspension is way too soft. Makes for an unbalanced ride.

The most obvious fix would be stiffer springs, but he doesn't want to sink much money into the bike, since he will most likely have a new one within a year.

I'm thinking of making some pre-load spacers for the fork springs, maybe playing with the oil level.

Any suggestions would be greatly appreciated.

Thanks!

 

[Canadian Dave]

Cheap fix would be to install a pair of stock springs out of a 1995 to 2006 KDX200/220. I'm confident they would be a direct fit. That would bump your fork spring rate from 0.3kg/mm to 0.35kg/mm, which would be a much better match with the stock 4.6kg/mm shock spring. Stock KDX fork springs aren't worth anything and I'm guessing if you ask nicely someone here will offer them up for next to nothing.

Anyone able to help BigBore out here?

David

 

[Sherby24501]

I have a set of stock 03 KDX220R fork springs - you can have them for the cost of packing and sending them

 

[glad2ride]

According to the MX-Tech spring rate calculator, he should be fine with the stock springs if his full weight in riding gear is between 30 and 42 pounds. If he doesn't want to lose that much weight, maybe he could just buy some new fork springs that are the correct rate (stiffness) for his weight in full riding gear. He could swap them back out with the stock springs before he sells the bike, then sell the used, stiffer springs on e-Bay.

You will coil bind the stock springs with a preload spacer before you ever get them close to the correct rate, so don't even waste your time.

Beyond that, there are compression adjsuters on the bottom of the fork. Lightly turn them all the way in. Please don't crank on them as they reach the full in position. Light clicks are all it takes.

Raise the oil level to the maximum. Besides that, try a heavier oil such as 7.5 weight oil.

Canadian Dave, nice to see you on here again. I have test fit some 1995 and newer springs in 1993 - 1994 KDX200 forks. They will not fit.

 

[paab]

What rate are the 220 springs? If they are .35s I'd like them for my 91 200 if they aren't taken. Or if anyone else has a set?

 

[Canadian Dave]

Gladtoride is it a length or diameter problem that prevents them from fitting? I've double checked by looking in my Eibach catalogue it’s telling me that they are a match? If they are too long any change you can make up for it by reducing the length of the preload spacer?

BigBore you could also stiffen them up by removing a couple of the active coils heating and rolling then end over and grinding them flat again. I couldn't tell you off the top of my head how many coils to remove though. That will depend on how many active coils the springs has now. Search the suspension forum, I'm sure you find more info there. You'll need to make up the difference in length by adding a longer preload spacer and can't go too much shorter or you will end up with coil bind.

 

[glad2ride]

Canadian Dave, as best I remember, the outer diameter is too large. What series springs does your catalog show?

There are no preload spacers in KDX USD forks, or for that matter, most (if not all) KX USD forks. The spring is engineered precisely to match up and there is no big gap to play with like on conventional forks.

The stock 1993 and 1994 KDX200 springs will run out of coil before they enter the (acceptable stiffness) zone. :-) That or you can run 7" of travel by way of travel spacers and pretend it is the good old days. :-)