Front spring replacement

I have a '07 YZ250F. I am looking to change my front springs, but it being my first time, I need some help. It looks a little intimidating with all the parts in the forks and I don't want to screw anything up. I am looking at getting the spring from Race Tech and there calculator recommends for my weight (230lbs without gear and about 250 with, and 6'4" tall, I guess their calculator figures it in) "Recommended Fork Spring Rate: 0.506 kg/mm". So which would be best the .48kg or .50kg, or does it really matter? The only thing I ride is Motocross tracks, no trails or anything else.

Is there a simple way to just change the spring in the front instead of having to rip everything a part? I looked through my manual, and need some clarification and hopefully someone has some tricks they learned to make it a easier process. If someone could explain the procedure or better yet a video. All I can find are videos about changing the oil seal, unless that's what I have to do to get at the spring, than so be it. This is a big time newb question, but looking in the disassembly instructions in the manual it shows only one fork spring, and that is the one that is changed out for the new spring, correct? I thought that there would be a spring in each tube. Do I need any special tools to complete this process? Would I also need any spacers? (I think I saw that the new springs from race tech comes with them).

Edited by cyber649

Thanks in advance for any help.

if you watch the video It's the best way to see how to do it , but ignore the part about changing seals

I would use 0.47 and 5.8 rear

each leg has a spring

Remember in a previous post of mine, we decided on the 5.6 instead of the 5.8 for the rear because the 5.8 was to stiff?

I must be reading the manual wrong for the front forks. It shows the fork spring as qty 1, unless they are just showing the one fork in the picture.

Edited by cyber649

lol sorry each leg has a spring

lol sorry.... read 250 not 230..each leg has a spring

I am assuming Race Tech's calculator figures in the weight of the gear as the calculator only asks for your weight without gear. When I put in my specs for MX Tech for 250lbs, it gives the same results almost, being that the rear spring they suggest is the 5.6, and the front .49.

What video would you suggest if you have one in mind?

So here are the numbers on the springs/shocks that I am ordering:

Front springs - .48 (maybe up it to .50?)

Rear shock - 5.6 (This is already ordered)

I will wait to here from you in case I should change any of these before I order.

This suspension stuff is confusing :thumbsup:.

I don't feel to comfortable changing the fork springs myself, so I may get someone else to do them.

Edited by cyber649

I would not go any stiffer than 0.48 , forks get real stiff real fast with the wrong springs , 0.47 is plenty IMO

5wt oil is the only one to use

you so need to drain the old oil

on the videos have a search on here and you will find a few good ones , you will need a fork cap spanner

Race Tech doesn't have a .47, so I will get the .48 instead.

Thanks for all your help!

try 4.6 then. I have read a lot of people having good results with EITHER what mog or Dwight have said based on their riding. If mog says 4.8 is too stiff, I'd go .46.

OR....and I know this is crazy, get 1 .46 and 1 .48 then you'll have .47. Unfortunately most places won't sell you 2 different springs but it NEVER hurts to ask!

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