[kootenaytallboy]

I've had an obtainium spring before, which was basically a 2.75" inch Ti spring in terms of free length that can nonetheless produce a 3" stroke because of the generous space between the coils.

I'm curious if other spring manufacturers' springs can do the same without over fatigue of the spring. The Diverse Suspension springs seem to work OK in this regard, but I'm curious if their 2.75" spring will get "worn out" due to flexing beyond its designed tolerances.

The reason I ask is that I have a buddy who had a 2.75" manitou that he had spring rate tested, and it measured at way less than the indicated rate (360 from 400). Not sure if it was always like this, as it was tested after several years of use.

Anyone have any thoughts/expertise on this?

 

[norbar]

Udi mentioned it's doable with RCS springs on FOX rc4's. I've had around 3 months of riding on my ti progressive spring that is also a size to small for my rc4 and so far so good. Though I got it really cheap so if something happens it wouldn't be that much of a problem.

 

[Gary]

I've been running a 2.5 on a 3" stroke shock for 2 years now. it's an older progressive spring with fewer coil winds than most and the free space between coils is far greater than 3". I'm sure it'll fail quicker than if fitted to a 2.5" stroke shock but I've had high end steel springs of the correct stroke fail (so not too fussed)
it's a 375 lb and def sits right inbetween the 350 and 400 steel springs in terms of sag and bottoming which is why I got it in the first place (couldn't find a 375x3.0 in steel or Ti at a decent price).

 

[Udi]

Like above, I've been doing it for years. First with a progressive (2.5 on 3) and now with a DSP (2.5 on 3).

It works fine as long as the spring has the physical ability to compress that far (preferably more to be on the safe side, for example the 2.5 DSP has an actual stroke of about 3.5, but you wouldn't want it on a 3.5 shock).

That said, you do it at your own risk, and it would just be unfair/stupid to try and claim warranty if it broke. Goes without saying, but I'm saying it anyway before anyone gets on my case.

 

[miuan]

Been running a 2.75" Progressive Ti spring on 3" shock for 3 years. No problems, but I prevent much preload and frequent bottoming. The theoretical stroke is huge due to few coils, but you can't compress it that far, just like any other element that's designed to bend some but breaks beyond a certain point.

 

[climbingbubba]

I had emailed DSP about it and they said in theory it would be fine but it would cause the coil to fatigue faster and of course it would void the warranty. I know of a few guys doing it though since it saves even more weight.

 

[kootenaytallboy]

I just got a response from DSP as well, and they said that it may or may not be possible with the 2.75 springs due to the slight variability in the space between the windings. They also said that they test their coils to full coil bind, and are very confident in the quality. Nonetheless, using a 2.75 coil on a 3" shock would void the coil's warranty.

Seems like you could measure spaces, but the best way would be to get the coil to a proper suspension shop to do a travel test.