[Wa-Aw]

I got this spring for my 8.75x2.75 DHX, have a new bike that has a 9.5" stroke and I want to know if it will fit. It's about 1cm shorter than the stock shock.

I find this size odd in that the spring rating for the 9.5x3.0 on my current shock is 350x3.25. Why would fox make a .01 difference in length in spring?

I also hear rumors that 300x2.75 stroke springs were all miss labeled as having a length of 3.24. I have also never seen a spring in 300x2.75(or 2.8) either so there may be some truth to this. Can anyone confirm? Kind of urgent question.

 

[Sandwich]

I can't really make heads or tails of your post, but a 3.24" spring is appropriate for a 3.0" stroke shock. For whatever reason, fox labels their springs with their free length instead of their shock application. In other words (I think), a 3.24byXXX spring has 3.24" of length before it binds. You don't want a spring to bind before the shock bottoms out.

TL;DR your 3.24 spring works on your 3.0 shock.

 

[HAB]

What he said.

 

[TWeerts]

I also hear rumors that 300x2.75 stroke springs were all miss labeled as having a length of 3.24. I have also never seen a spring in 300x2.75(or 2.8) either so there may be some truth to this. Can anyone confirm? Kind of urgent question.

can anyone confirm this? my sx trail has a 9x2.75 shock with a 3.24" spring...

 

[Wa-Aw]

Sorry my first post was a bit rushed and is a bit confusing.

What I meant was that I think (or am pretty sure) that this 300x3.24 spring I have is actually a miss labeled 300x2.8 spring. I think this because 1) I read it somewhere on the internets and 2) because fox springs for 3.0" stroke shocks are labeled as having a 3.25" stroke. I'm not sure why on earth they would have a 3.24 stroke spring AND a 3.25 spring, hence the assumption that it is actually a 2.8 spring, especially since it was for a 2.8 stroke shock. I bought the spring aftermarket though.

What I want someone to tell me is that it really is a 3.24" stroke spring and I can use it, but I'd rather not make the mistake. My other option is to get a 300x3.75" spring since the 300x3.25 springs are sold out, would this fit on a 9.5" DHX?

Here is a pixtor of my scythe at bottom out with the supposed 3.24" spring. Should I be seeing gaps in those coils?

 

[IH8Rice]

can anyone confirm this? my sx trail has a 9x2.75 shock with a 3.24" spring...

they do make a 2.8" spring

 

[kidwoo]

Should I be seeing gaps in those coils?

No but you should be building landings.

 

[HAB]

they do make a 2.8" spring

Yeah but it's supposed to be used on 2.5" stroke shocks. I can pretty much guarantee that they don't have their tolerances on spring strokes down to .05", so using one of those on a 2.75" stroke shock could go kinda badly. As Sammich noted, Fox labels their spring with the absolute max they can compress before binding, unlike the shock stroke they're designed for, like everyone else does. You want to leave yourself a little wiggle room.


In answer to the OP's second post: I have no idea if Fox ever mislabeled some springs or not. Am I right in thinking from your first post that the shock on the new bike came with a spring that's not the right weight, so you want to use the one off your old bike? And that the stock spring from the new bike is 1cm longer in total than the one off the old bike? What's the weight on the stock spring from the new bike?

 

[IH8Rice]

Yeah but it's supposed to be used on 2.5" stroke shocks. I can pretty much guarantee that they don't have their tolerances on spring strokes down to .05", so using one of those on a 2.75" stroke shock could go kinda badly. As Sammich noted, Fox labels their spring with the absolute max they can compress before binding, unlike the shock stroke they're designed for, like everyone else does. You want to leave yourself a little wiggle room.

i thought that their 2.55" spring was for their 2.5" stroke shocks
http://www.jensonusa.com/store/product/RS286C01-Fox+Shox+Spring+Dhxvan+25-275+Stroke.aspx
http://www.cambriabike.com/shopexd.asp?id=94427&page=Fox+Dhx+Coil+Spring

 

[Wa-Aw]

Yeah but it's supposed to be used on 2.5" stroke shocks. I can pretty much guarantee that they don't have their tolerances on spring strokes down to .05", so using one of those on a 2.75" stroke shock could go kinda badly. As Sammich noted, Fox labels their spring with the absolute max they can compress before binding, unlike the shock stroke they're designed for, like everyone else does. You want to leave yourself a little wiggle room.


In answer to the OP's second post: I have no idea if Fox ever mislabeled some springs or not. Am I right in thinking from your first post that the shock on the new bike came with a spring that's not the right weight, so you want to use the one off your old bike? And that the stock spring from the new bike is 1cm longer in total than the one off the old bike? What's the weight on the stock spring from the new bike?

You are 100% correct good sir.

Old bike was a Scythe and new bike is an M9. I just can't get it to feel right with a 350 no matter the shock position, tried out a friend's 300 and it just came to life! A bit soft but i can mess around with the compression adjusters in that case.

Kidwoo, we were testing cameras in that shot.

 

[HAB]

A heavier spring will be a little longer. I bet you're fine, but don't have a great way to verify that.



IH8Rice: My memory was that they did a 2.35 for 2/2.25" stroke shocks, a 2.8 for 2.5 strokes, a ~3" for 2.75s, and a 3.25 for 3s. I could be wrong though, it's been a long time since I've run a Fox coil shock or spring on anything.

 

[Wa-Aw]

Thanks HAB, that's what I wanted to hear.

There's gotta be some way to measure how much travel a spring has by the lenth of the spring and the distance between the coils. Just to get a ball park figure. I heard spring binding in shocks can be pretty catastrophic.

 

[HAB]

There is, if you know material, number of winds, diameter of the wire it's wound from, overall length, and spacing between winds. Don't remember off the top of my head and don't have time to look it up now, but probably could later if you can get me accurate info on all the stuff I just mentioned.