Just ordered my firts dh bike with a coil shock, TF Tuned spring calculator says i need a 310lb spring. I can get either a 300 or 350 and not sure which one to get? How much adjustment do you get with a coil shock?

get a 300 and a 325. try both and see which you prefer.

Dont seem to be able to find a 325. Its a rockshox kage shock 240/76. Any idea where i can get a 325?

http://www.chainreactioncycles.com/nukeproof-rockshox-vivid-steel-spring-3-/rp-prod85628

You owe me a pint

Ah, cheers. I assumed they wouldnt fit as it says length is 166 or 165, but im guessing thats not the eye to eye length then? What does the 165 or 166 refer to?

165/6 refers to overall spring free length. 76 refers to shock stroke.

240 refers to eye to eye length but is somewhat irrelevant to choosing your spring as it’s possible to have differing eye to eye lengths but the same stroke length and vice versa.

last time I was facing that decision I gave TF a call, told them what bike, what shock and they advised which way to go and I bought the spring from them. Customer service at it’s best.

So does the 1mm difference beyween the 165/166 really make any difference? Im buying it for a bike which hasnt arrived yet so have nothing to measure. I rang TF who said to have a slightly higher rated spring for jumps/drops and a lower one for smoother stuff so i think it would be handy to have the two really, especially at the price on crc.

And seems a bit odd if you look on other shops at shock springs they dont have the spring free length options?

I’d go with the really helpful guys you spoke to at TF 😉 few quid more but they have given you free advice so far an will probably be able to sort you out.

Id be happy to go with tf but they only have an option of 300 or 400lb springs, ideally i would want a 325 if possible

I’d go with the 300 as you’ll need a little preload on it. 1mm of preload will give you that 310 lbs for the first inch and 610 for the second. That’s only 10 lbs less at the end of a two inch stroke than getting a non existant 310 spring. Besides, two “identical” springs would give you a bigger variance than that. I’ve got a 750 that’s softer than a 700. Don’t know which is off, just know which I like to ride when.

So then would the 166 length one give you an extra 1mm of preload over the 165? (before adjusting anything)

TF who said to have a slightly higher rated spring for jumps/drops and a lower one for smoother stuff

“really good advice from TF”? er.. No mikewsmith not this time 🙄 .
Why would anyone want a softer spring rate for smooth terrain? think about this for a minute, eh?
the difference between a 300 and 350 will be slightly more sag and slightly easier to bottom out. some riders like to run more sag than others. I do.. it’s entirely down to personal preference. a softer set up can offer more grip in really muddy/soft conditions as well as a lower BB for more stability. A stiffer spring will be better for pedalling (ie. smooth flat terrain)

that extra 1mm free length is irrelevant.. ideally you never want to run more than about 2 turns of pre-load on any coil spring.

spring rate tolerance/variance is an even bigger reason to have more springs to choose from, try and decide for yourself.

yeah know nothing idiots
http://www.ixsdownhillcup.com/en/-Tim-Flooks-is-SRAM-s-new-mechanic
My previous experience was really good, exceptionally knowledgeable and honest.

we all know you are the DH god but had some better sounder advice from those guys. Where you placing at Lourds?
Why would anyone spec a DH spring for smooth trail?
For most people getting within 100 on the scale will be good enough 😉

They are not talking about fireroads, they clearly mean that if you aren’t doing 5ft+ drops then there is no point setting up your suspension to do so, you are much better setting it up to absorb the activity of rattling through rock gardens.

I have the suspension setup on my downhill bike softer than most recommend because I don’t do big air and I prefer the control it gives me.

Tim Flooks is great at what he does.
This does not mean every piece of information relayed over his telephone is gold.
I lived local to the original TF workshop when he first opened and as he wasn’t crazy busy I spent an afternoon with him setting up my shock. He was brilliant and I left with pretty much everything I wanted done. Most riders don’t even know what they want, nevermind able to convey it in a short telephone call.

Don’t try to turn this into some personal gripe it only makes you look sad and bitter.

Only getting with in 100lb of your ideal rear shock spring weight means your fancy DH bike was probably a bit of a waste of money. Do you even realise how huge that is now that almost all DH frames run very low leverage ratios?

Do you even realise how huge that is now that almost all DH frames run very low leverage ratios?

So to say that going X or Y without knowing the frame or the rider etc is a bit of over reach.

There is a rider here. and he’s been already been quoted a 310lb spring by TFs calc for his 3″ stroke shock DH bike.

You can’t seriously be saying a 210lb or 410lb spring would be adequate unless you are either completely clueless or just looking for a pointless argument.

give it up, please.

Ive ordered a 165mm 300lb spring, they have 166mm 325 springs so ill get one of those if i dont get on with the 300lb one

What does the bike come fitted with?

Its either 400 or 450

To answer the OP’s questions

Either a 300 or a 325 will probably be OK, assuming the calculations you’ve done are correct. It doesn’t need to be absolutely perfect – Being 20-30lbs out probably won’t be a problem, and it depends on the terrain and your style of riding anyway.

Frustratingly, some manufacturer’s springs are softer than others’ for a given spring rate, so you never know quite what you’re getting until you try it. If you can find some used springs to try out before you buy, even better. You can always sell them on if they’re not right.

To a certain extent you can adjust sag with preload but it’s not advisable really. Ideally you want just enough preload to hold the spring snugly on the shock and not rattle. You may also be able to adjust compression damping depending on the model of shock you have (Kage R? Kage RC?) but again this is a bit of a hack and shouldn’t really be used to compensate for a wildly-incorrect spring.

The other option is to try it with the 400lbs spring. If you find you’re only using 50-60% of the travel then consider swapping for the 300lbs one. If you’re getting more like 70-80% then perhaps 350lbs would be better for you. Obviously this is just a very rough estimate, and bear in mind that brand new springs can soften slightly in use.

Cheers for the response. Its a Kage RC shock. Ill definatley be trying it out with the spring that comes on it as i wont have the lighter spring till a few days after the bike arrives and i dont think im going to be waiting that long to take the bike out!

Is Tim Flooks still at TF? I thought he sold it.

Flooks works there still but is not the owner now iirc.

http://stendecworks.com/springs/

… and just to confuse things even further, ‘budget’ springs can have manufacturing tolerances of +/- 15%, so that 300lb spring could be anywhere Btw 250-350lb!!

rocketman – Member
http://stendecworks.com/springs/

Hmm…. when I read about those on Vital, it was “lighter than titanium for half the price” – that reads more like “about the same weight as titanium for the same price”