Just looking into this and found that the 12+ shock spring is 12kg/mm and according to racetech calculator i need roughly 11kg/mm. What does this relate to when looking for a spring which seem to be rated 90 95 100 105 etc Then to top if off the likes of ktech use N as the measurement as opposed to kg. They dont half make it difficult!
Mate, a mass of 1kg exerts under gravity a force of 9.81N (for practical purposes, call it '10'). So to convert spring stiffness from kg/mm to N/mm just multiply by 10 (I mean, you can multiply by 9.81 if you want, but I imagine it wouldn't make much difference). So springs you're talking about that are rated as "90, 95, 100, 105 etc" will be having their stiffnesses quoted in N/mm. For example, a spring of 105N/mm is the same stiffness as 10.5kg/mm. If you're looking for a spring stiffness of 11kg/mm, that that would be equivalent to a stiffness of 110N/mm. Hope this helps!
Just give them a phone mate. They'll be able to recommend a spring rate for you based on you're details.
Thanks abz much appreciated. So im guessing riders of a similar weight to me (75kg) are using around about 105 or 110 rate springs? Just trying to confirm the calculation i made on racetechs website.
Been trying this morning but no luck. Im more curious at this stage than anything. If im on the phone too long i will end up a few grand lighter!
Yeah I know what you mean mate. I am saving a bit of cash at the moment to sort the rear out. Just not sure what to go for Nitron or K-Tech. There's not much difference price wise in their top end shocks.
Is that for racing tuktuk ? if not those spring rates seem a bit high for a 75kg rider on a sports bike, I had a 105 in my R1 but i'm 110 kg The 105 was recommended by ktech and I could get static and rider sag spot on with it, for track use.
Just road riding with occasional track day. This is what comes through racetechs calculator. Is 12kg/mm the correct figure for 2012 showa rear shock? I dont know why there cant be some sort of chart available to give some indication All very confusing to me!
If you're struggling still, call JHS Racing and they will give you some great advice/recommendations. Sent my Ohlins TTX for a rebuild there recently and they have been absolutely fantastic over the phone and via email. Getting it resprung with the correct weight spring as well.
Just tried that calculator with my weight on the R1 and it agreed with the Ktech recommendation. But to make sure I'd do what TW4T50N suggests and speak to a suspension company like JHS or MCT
I'm rocking 83kg and using 105 spring in the Ohlins TTX.... got the sags spot on after a few turns of preload. Be careful as I was warned about different linkages and how they operate at different ratios, James Hillier uses a 85/90 in his K Tech DDS and not far off the same weight, purely because the linkage compresses the spring at a different rate. I looked into the 105 specs from Ohlins and stated 16 stone rider and I'm far from that! Also weight yourself fully kitted your be surprised how much more with your gear on, I'm currently running a Dainese DAir suit that's quite a bit heavier then your normal average suit, so bare all that in mind.
Cheers for all the help guys. Dave is that 83kg kitted up as im probably not far off that with gear on?
I agree Dave the linkages make a difference I am 16 Stone so would need a much stiffer spring on the Honda compared to the R1 I had a 105 on an Ohlins shock on the R1 but would need 130 on the Honda
Yeh I wish!..... 83 without gear, but just with jeans tee shirt etc, I did do the weights last year with an Alpinestars suit Supertech boots and GP pro gloves, NXR Lid and was surprised how much more it was.... will have to try with the Dainese suit on, the Dainese Axial Pro inner boots are super light but like I said the D/air suits weighs considerably more than the Alpinestars Atem I was running at the time, Putting this down to the fact it's 2mm suit. Even the Xspirt lid weighs more, just a few more grams, it all adds up..... time for some dieting
Heard back from ktech Hi Thomas The spring supplied on the shock is 105N, you may want to go down to a 100N spring depending on what you are using the bike for. So its there or thereabouts which is good to know!
I think your be bang on the money with that if your not too far off my weight.... the only flaw with the K Tech DDS lite is once it's fitted in the bike you can't adjust the spring preload! So you could be taking it on and off to make the spring preload adjustments till its right.... you have to buy the DDS Pro to get the remote adjuster..... I know once it's set it's set.... but couldn't be doing with the hassle... plus I know a few people that have had some damping issues with brand new shocks! Pretty isolated...... James spat its dummy out causing that situation at ballascary
