Titanium Springs?

[DugB]

Hello all,

I've posted before about how much I love the K2 4000 I picked up recently. It's a Way Big, so I'm trying to knock off the weight where ever I can. Right now I'm running all XTR M950/M952 components which certainly helped, as well as kevlar bead tires, and am now looking at those heavy shock springs...anyone know where I can find titanium springs to fit this bike? I'm sure anything marketed for this bike disappeared a long time ago, but also believe that there must be springs for more recent shocks that would work.

I've seen that one on eBay...I'm keeping it in mind but am not sure it will fit...I don't have my shock & spring measurements on me right now.

Many thanks in advance for any information you may provide!

- Doug :-)
Falls Church, VA, USA

[bike kid]

What kind of shock is it?

[shovelon]

Doug, I think the spring listed on Ebay is somewhere 425 to 450lbs. which puts it close. My Noleen had a 500lb. spring on it, and when i installed the Manitou Swinger coil, I purchased the 450lb spring and had to OD grind it to about 425.

So if it fits over the shaft, and you are not too heavy, I think the spring rating is OK.

[DugB]

Thanks for the responses! I think the rear on the 4000 was a Noleen NR4...I forget the spring rate. The front shock is currently the K2 SmartShock, which seems to have the same dimensions as a Noleen. The electronics aren't working on it, though, and I may end up either removing the excess weight from it, or replacing it altogether. It doesn't finction well even without the "smarts"...just wish it didn't have that little bit of dead (unsmart) weight.

I'm only thinking about cheaper springs that might come up on eBay...it's hard to believe that people would pay upwards of $200 or more retail for just a spring. Maybe I'll just wait for Callum to come out with some crazy upgrade kit ;-) I do bet he's a bit surprised by all the 856 owners crawling out of the woodwork looking for springs. Glad to see that he's still raking in the business.

- Doug :-)

[rapiddescent]

hmmm, the k2 4000 is a great XC bike with just the right amount of travel - why compromise that to save a 100 grams?  The Ti spring will pretty much lock out the shock.  I had a sneaky ride on Nora Roesche's (world XC K2 team rider, 1998) bike.  She must have only weighed about 60kg yet her Ti NR4 did not move at all when my fat ass sat on her bike (82kg)

callums top weight saving tips:

a) go for a crap (saves about 2lbs)
b) change the inners and tyres
c) then go for a ride and not worry about the weight !!!
 
:-)

callum

[orange]

on a similar theme - I heard that Henrik Djernis' world cup winning bike in 1996 had a solid rear end even though it appeared to have elastomers - the shaft down the inside was fixed so the rear didn't pivot. Is this true?

[dcarr1971]

callums top weight saving tips:

a) go for a crap (saves about 2lbs)
b) change the inners and tyres
c) then go for a ride and not worry about the weight !!!

  Nice, I might be able to save more than 2lbs on a)...not that I'll ever try to confirm that...

  I wreck my tubes too often for b) and just go with c) all the time.

   

[shovelon]

hmmm, the k2 4000 is a great XC bike with just the right amount of travel - why compromise that to save a 100 grams?  The Ti spring will pretty much lock out the shock.  I had a sneaky ride on Nora Roesche's (world XC K2 team rider, 1998) bike.  She must have only weighed about 60kg yet her Ti NR4 did not move at all when my fat ass sat on her bike (82kg)
callum

You lost me there. How does the Ti spring lock out the shock?

I have a 300lb ti spring/NR4 combo mounted on my 956LE, and it works just great. Much more linear than the Noleen spring. The 450lb spring on the 4000EVO should work great.

Were you thinking of the 3000 Strut bike?

Terry

[DugB]

The rear shock on my 4000 has a rate of 600, and the front something like 225. Together they average 400, which would be good for that eBay shock, right ;-)

Ah, if it were only that easy...

I'm almost tempted to see what that 450 rate spring would act like on the rear of my bike, with it preloaded a bit. Right now I run the 600 with almost no preloading (I weigh about 160 lbs and my bike is Way Big size).

I doubt I'll be able to find a replacement for the front, 225-rate spring, though, and wouldn't want to chance the "belt sander" method. Ideas?

As a weight weenie sidenote I swapped saddles last night and took off a noticeable amount of weight. I guess those thick gel a$$pads in my Selle MetroGel saddle were a little overkill, right? :-)

- Doug
p.s just setup that new 856 I got for my wife, and we went on the first ride a few days ago. She was surprised how well she liked it, and was certainly pumped by my repeated comments about how good she looked on it ;-) She's about 5' tall riding an 856 medium...yeah, a little large for her. Suddenly, a loud voice roared from the mountain: "Let the new hobby, and its seemingly unnecessary expenditures, be justified!" :-)

[shovelon]

The rear shock on my 4000 has a rate of 600, and the front something like 225. Together they average 400, which would be good for that eBay shock, right ;-)

Ah, if it were only that easy...

I'm almost tempted to see what that 450 rate spring would act like on the rear of my bike, with it preloaded a bit. Right now I run the 600 with almost no preloading (I weigh about 160 lbs and my bike is Way Big size).

I doubt I'll be able to find a replacement for the front, 225-rate spring, though, and wouldn't want to chance the "belt sander" method. Ideas?

As a weight weenie sidenote I swapped saddles last night and took off a noticeable amount of weight. I guess those thick gel a$$pads in my Selle MetroGel saddle were a little overkill, right? :-)

- Doug
p.s just setup that new 856 I got for my wife, and we went on the first ride a few days ago. She was surprised how well she liked it, and was certainly pumped by my repeated comments about how good she looked on it ;-) She's about 5' tall riding an 856 medium...yeah, a little large for her. Suddenly, a loud voice roared from the mountain: "Let the new hobby, and its seemingly unnecessary expenditures, be justified!" :-)

I think the 600lb spring would work nice for a Clydesdale rider. My Oz came with a 500 lb spring, and got only 1/4 inch sag. My Manitou shock would not budge with a 500 spring, and I weight like 190 lbs. I ended up swapping the 500 spring for a 450, and then fine tuned it for 1 inch of sag.

You and your wife have matching 856s?  My wife and I have matching 957s. She is also 5 foot.

[DugB]

It's funny...my K2 4000 actually works well with the 600 spring on the back...it's probably right, but maybe a bit on the stiff side given the lack of preloading I use. I may give one of these 450 rate springs a try, just to see. No clue where I'd find something to work on the front, though...450 is a big difference from 225! :-o

Went on my first true singletrack ride for this bike last night, and I must say it handled well. The tall frame was a tad squirly for me, so I wasn't able to immediately do a few of the narrow bridge crossings that occur immediately after sweeping left or right turns...I'll get the hang of it, though, as I've always used taller frames. The shocks were very responsive, as I could hear the occasional "woosh" on big hits, like the struts on a car. No leaking oil or anything like that either. I'm very happy with this old ProFlex/K2...now to get the 856 I'm building up back on the road...if Callum ever decides to sell those COR springs he's hording ;-) hehehe

Just kidding, of course...he should sell ad space on the RDS site, though, because I've been checking his "Products" page more often than CNN.com :-)

- Doug

[Colin]

hmmm, the k2 4000 is a great XC bike with just the right amount of travel - why compromise that to save a 100 grams?  The Ti spring will pretty much lock out the shock.  I had a sneaky ride on Nora Roesche's (world XC K2 team rider, 1998) bike.  She must have only weighed about 60kg yet her Ti NR4 did not move at all when my fat ass sat on her bike (82kg)

callum

Hi Callum,
I think that you’ve mentioned before that you don’t think much of Ti springs as suitable for our bikes?
Is it possible that the team bikes’ suspension were intentionally “locked out”??

I’ve refrained from commenting before ‘cos I’m sure that you must have done your research for your excellent COR retrofits, but here’s my experience……….

I have Ti springs fore and aft on both my 4000se and XP-X (856), I weigh 95kg (209lb) with kit.



4000se
Front: Rated 200lb, weight 78g (Steel = 114g) NR-5 Crosslink
Rear: Rated 550lb, weight 148g (Steel = 286g) NR-4

XP-X
Front: Rated 200lb, weight 71g (Steel = 213g) ODS Vector II
Rear: Rated 350lb, weight 78g (Steel = 234g) ODS

Now that’s not much of a weight saving (more obvious on the XP-X) but every little helps and on the plus side they don’t rust (and they “do sure look purdy”! <GRIN>)

From what you write, you seem to be saying that you don’t expect Ti springs to compress? (In a way I agree with you, I thought Ti was a “brittle” metal) but these coils work fine on my bikes (for the last 3 years), full travel compression and they feel linear and indeed maybe a little more sensitive to the small bumps in the first part of compression.

I’m a convert!

Col.

[orange]

Is it possible that the team bikes’ suspension were intentionally “locked out”??

I heard that Henrik Djernis' world cup winning bike in 1996 had a solid rear end even though it appeared to have elastomers - the shaft down the inside was fixed so the rear didn't pivot. Is this true?

<----- what I said earlier, though I heard it re elastomers rather than Ti springs

[shovelon]

<----- what I said earlier, though I heard it re elastomers rather than Ti springs

I too heard that  it was elastomers, but with a tube inside to lock it.

[rapiddescent]

funnily enough, I was at the factory today picking up the last of the COR springs.  I was chatting to the guys about Ti springs and their manufacturing process and whether they could make them.  Apparently, some racing cars are now using Ti springs and they had heard about mtb's using Ti springs - but the cost is very prohibitive.  We are talking around 400 UKP (US$800) per spring and anyway, they just didn't think that they'd be able to work with Ti satisfactorily.

I notice Colins  two coiled Ti spring.  frightening stuff.  I actually recognise that as a standard DIN square edge spring and will ask around my suppliers (apart from the spring factory).  Don't use the plastic washers.  get some CNC'd ones instead.  the plastic will break.  The only way to get that Ti spring to compress was to give it only a few coils...!!!

callum
rds