Jump to content

Spring length questions - '14 YZ450F

Recommended Posts

So bought this bike a while back, and replaced the springs with some the right size for me (prev owner was much larger).  Noticed the front end was still super stiff.  Didn't bother me too much on the track but in the woods it was miserable.  Seals were leaking, so today I pulled them apart to replace the seals, fluids, etc and to do some valving.  Noticed this time that there is quite a large spacer sitting above the spring perch....hmmmmm.  Don't have one of those in my other SSS forks and looked at the manual.  Not a stock spacer.  The spacer is 35 mm long...so quite big. Hmmm..

Got the springs I removed from the bike off the shelf and measured them... 462 mm more or less.  Free spring length spec is 497 mm, so the 35 mm spacer was obviously there to make up the difference.  The problem is my new springs are 489 mm free length, so with the spacer I've got a butt ton of preload.  No wonder the front end felt stiff in the woods....

So, here are my questions:

1.  Surely I should remove the 35MM spacers, correct?

2.  My springs free length is 489 mm, which is a little below the low end of the spec.  The springs should be 497 with a low side of 492 mm.  I have 4 of the washer type spacers that came with the springs.  If I put two together they measure around 3.5 mm, so if I add them to the forks I'll be at the low side of the spec but I will be in spec.  I should add them, yes??

3.  If I do add the washer type spacers, do I add them to the top of the springs up against the perch, or at the bottom?

I've always just thrown new springs in my forks and never really measured them.  I see now that was a bad idea!!  

Share this post


Link to post
Share on other sites

The std fork is preloaded a tad too much I seem to remember, 8mm std and most prefer 4-5mm , So I would run say 3mm less than std

Share this post


Link to post
Share on other sites
The std fork is preloaded a tad too much I seem to remember, 8mm std and most prefer 4-5mm , So I would run say 3mm less than std


Thanks Mog. Running the 2 washer spacers would pretty much put me there. They go between spring perch and spring or between spring and bottom of fork tube?

Share this post


Link to post
Share on other sites

Those large washers / spacers go at the bottom of the tube.

I've read somewhere that you shouldn't stack more than 2 high,

if more preload is necessary, better to address it from the perches.

Share this post


Link to post
Share on other sites
1 hour ago, mlatour said:

Those large washers / spacers go at the bottom of the tube.

I've read somewhere that you shouldn't stack more than 2 high,

if more preload is necessary, better to address it from the perches.

Thanks!  

I'm the king of putting stuff down and not being able to find it.  Could not locate the two washer/spacers that I measured yesterday, but still had the other two.  Looked all over the house and garage for them and couldn't find them.  Ended up just using 1 per leg since I could only find the 2.  Of course, as soon as I put the forks back on the bike I found the two missing ones, sitting right next to me.  

Figured I'll go ahead and try it like this, and if it dives too much or acts strange I'll open them back up and put in the additional washer on each side.  I've still got the large spacers I took out, so I can always cut them down to a shorter length if I find the 1 or 2 washers is not enough.

  • Like 1

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:


×