coil shock what spr...
 

  You don't need to be an 'investor' to invest in Singletrack: 6 days left: 95% of target - Find out more

coil shock what spring weight ? trek slash

11 Posts
8 Users
0 Reactions
2,888 Views
Posts: 3072
Free Member
Topic starter
 

hi

i've been considering a coil shock for a while now and merlin have the right size at a good price. DHX2 (230x62.5) in various spring weights to fit my Large trek slash 9.7 2023 (gen 5).

spring are 2.8" and 400/450/500/550 lbs weights

i've plumbed the numbers into ride fox calculator and for my rider kitted out weight 89kg + 6kg , I'm a 400lb spring or 450 spring (if carrying a bag etc) , it seems everyone on line are using heavier (or in some cases shorter springs), even on the slash fb group i'm getting little response.

can anyone advise, give us useful info , this guys video makes alot of sense (until he says he's using a 500lb spring, when he's 10kg lighter)

hardware wise i'm coming of a float x2 so likely same fittings, but i'll order new bushings.

i want a good ballpark, so can then buy a lighter or heavier spring,

TIA


 
Posted : 09/08/2024 11:24 am
Posts: 271
Free Member
 

Plugged your figures into the Ohlins spring calculator as a comparison - gives 502lbs at 30% shock sag

I'd go for 500lbs weight.


 
Posted : 09/08/2024 11:34 am
Posts: 30093
Full Member
 

Do you want stuck to the ground grip, or are you a jumpy type?


 
Posted : 09/08/2024 11:47 am
Posts: 40225
Free Member
 

TF Tuned calculator puts you on 480lbs-514lbs depending on sag. So 500lbs is closest.

How is the Fox calculator so much lower? Does it differentiate by suspension layout?


 
Posted : 09/08/2024 11:48 am
Posts: 271
Free Member
 

Also....what are you wearing/carrying that you have an additional 6kg of weight??


 
Posted : 09/08/2024 11:49 am
Posts: 147
Full Member
 

Hi,

I've the same size shock on my Kenevo and have 550 and 600lb springs spare, let me know if you want to borrow one.


 
Posted : 09/08/2024 11:54 am
Posts: 13771
Free Member
 

Spring rate is tricky, two riders the same weight can prefer different springs, depends on riding style, bike, and lots of other factors

500 sounds like a good start point for you


 
Posted : 09/08/2024 12:18 pm
Posts: 3072
Free Member
Topic starter
 

thanks all, i'll go for a heavier spring,

6kg of weight? two water bottles, tools, spare tube helmet kneepads shoes, etc.  i maybe overestimating :0)

details entered as below

https://tech.ridefox.com/bike/general-info/672/sls-and-standard-steel-rear-shock-spring-information

Input Parameters (last two wasnt sure so left as is)

Measurement Units Standard    Metric

Total Riding Weight (kg)  93

Rear Weight Bias (%)   60

Rear Wheel Travel (mm) 160

Shock Stroke (mm) 62.5

Shock Sag (%) 32

Preload Adjuster (n.n) 1

End Coil Effect (%) 60


 
Posted : 09/08/2024 1:05 pm
Posts: 40225
Free Member
 

Yeah I'd start with the 500 and perhaps look for a compatible 475 spring later if need be.

That's what I have on my trail bike (EXT spring though).


 
Posted : 09/08/2024 1:33 pm
Posts: 10225
Free Member
 

Just a thought on coil shocks - if I could have my time again I’d buy a shock with a hydraulic bottom out. Based on cost it would probably be a super deluxe coil or that new vivid coil.

I found with my Sentinel that unless I ran quite a stiff spring it bottomed out too easily with my riding style / a Cane Creek Kitsuma coil shock. That was with the frame providing 24% progression. I tried a progressive coil but didn’t like the 2 obvious rate feel to that. In the end I stick a cascade link on to take it to 30% progression and it feels great now. I’d still like an hbo shock though.

https://www.bikeparts.co.uk/products/rockshox-rear-shock-vivid-coil-ultimate-rc2t-standard-standard-c1-230x62-5mm?currency=GBP&variant=45755923759261&utm_source=google&utm_medium=cpc&utm_campaign=Google%20Shopping&stkn=a894e8283159&gad_source=1&gbraid=0AAAAAC6PGhx_3toZi9ehc0yLD-6I3wgNb&gclid=EAIaIQobChMIwquDgIHohwMVt5dQBh2GgynkEAQYASABEgLxuvD_BwE


 
Posted : 09/08/2024 2:30 pm
Posts: 1594
Free Member
 

I've been running coil shocks on trail bikes for a long time and I've always found it better to run one spring rate higher than recommended.  It gives you back some of the pop/climbing ride height of an air shock, with minimal negative effects.


 
Posted : 09/08/2024 2:37 pm
Posts: 3072
Free Member
Topic starter
 

thanks all ordered the 500lbs, sounds like the ideal starting point.


 
Posted : 09/08/2024 4:09 pm

6 DAYS LEFT
We are currently at 95% of our target!