how can i find out the spring rate?

[toalco-kdx]

how can i find out the spring rate for my fork springs? im about 190# and i dont bottom the fork much so im pretty sure there not stock but i'd still like to know what they are. so how can i?

 

[fatty_k]

If they arn't stock, there should be a number etched into the bottom of the spring. My stock springs had no markings.

 

[toalco-kdx]

can i just take the top of the each fork tube off without anything happeneing? the spring isnt under much pressure is it, could it go flying when i take the top off? ive never done it before so dont know what to expect. thanks

 

[wibby]

If your bike is a stock Kawa and you think the springs are still stock go check out www.buykawasaki.com and look up your model, it should show the stock springs were and what optional weights came that year.

 

[canyncarvr]

re: 'can i just take the top of the each fork tube off without anything happeneing?'

Possibly so, possibly no.

Obviously, taking the caps off each tube with the weight of the bike still on the forks would be a problem. ;)

Support the bike so there is no weight pushing on the springs, and it won't be a problem. Note that with NO weight on the front (forks fully extended) their will be force pulling against the caps, not pushing against them.

Much easier to do with the forks out of the bike...but if you choose to not do it that way, be careful with the caps. Unthread it until you hear/feel the threads 'click', then with slight pressure on the cap, it will come out of the fork tube.

BTW..if you DO take the forks out of the bike, loosen the fork cap (after loosening the top clamp) before you remove them. That will keep you from struggling to hold the fork tube when you wrench on the cap. Sure..a vise is fine, but make sure you protect the tube!

Of course, taking the cap off won't get you a loose spring. You still have to loosen the cap from the rod nut. You can do that with a couple of wrenches. Fashion a piece of sheet metal with a slot in it to go a round the piston rod, but hold the spring under the jam nut. That will make it a lot easier to get to the nut/cap. You don't have to mess with holding the spring.

A wrench of the proper size can be used as a spring holder in lieu of a slot cut into a piece of sheet metal.

Anyway.......you can check any spring by measuring the force required for compression against its length change.

Right?

If you have a 470mm long spring to start with...put a 21lb. weight on it to compress it 1", you have a 21lb/inch spring.

Sure..you could put a .kilogram of something on it and measure a mm of compression. Have fun with that!

There are spring tools made for such measurement. You could use a bathroom scale and a known weight, too. Use a pre-cut piece of dowel (for example) as the measurement device.

You would be much better off taking them to a shop and asking them to check them for you.

Whew!! THAT would be much eaiser, 'eh?