Is a spring rate change from 0.42kg to 0.40kg enough to really notice?

[211]

New bike, new suspension (Beta 200 Race KYB).
Race Tech's spring calculator suggests I run a 0.40kg/mm spring rate. Stock rate is 0.42kg; so 0.02kg lighter. 

I'm not a professional, and 0.02kg/mm doesn't seem like enough to notice. In fact if I play with the calculator I can get it to spit out .42kg suggestion. I.e change my age  to "standard age- up to 29". 

 

175lb rider, fast B-class, woods and semi-hard enduro.

I'd rather use the money to go towards gold valves and the associated shim stack. 

[tom02cr250]

It is a noticeable difference. But do you think you need softer forks? I think you should stick with the .42 based on your weight and speed. Their spring rate calculator is a little on the soft side, plus it only factors in about 15 lbs of weight for all your gear. I would just open up your clickers if you wanted it softer vs a spring change. But those forks could use a revalve to make them more plush for you, if you feel they are too stiff, I'd put the money towards that. 

[211]

1 minute ago, tom02cr250 said:

It is a noticeable difference. But do you think you need softer forks? I think you should stick with the .42 based on your weight and speed. Their spring rate calculator is a little on the soft side, plus it only factors in about 15 lbs of weight for all your gear. I would just open up your clickers if you wanted it softer vs a spring change. But those forks could use a revalve to make them more plush for you, if you feel they are too stiff, I'd put the money towards that. 

Ultimately I'd like it a tad more compliant up top without sacrificing the aggressive handling that I enjoy with the KYB's. 
I do sit a bit high in the stroke but I think that's pretty normal for KYB. 

I didn't want to pull the trigger on a revalve if I could get similar results from a spring change. 

I don't think the .42 rate is wrong necessarily and I ride with way more than 15lbs of gear so I'll probably keep it as is.  

[tom02cr250]

I have revalved one of these bikes and rode it, along with lots of other kyb's, I'd recommend a revalve to make it more plush and softer. The softer spring would make them feel better but a revalve is better. 

[Fun Police]

as an owner of one of these things who weighs about the same, keep the stock springs or go up, not down

You'll get more compliant travel riding a tad higher up

going to a softer setup is going to put you in the hydrolock at bottom out sooner and they'll actually feel rougher

 

If it's a 2023 or 2024, don't touch the valving, go up a spring rate

I went up two on the rear just fyi

 

Similar terrain to cascadia just dryer. But just as rough and rockier

Edited April 26, 2024 by kidwoo

[Radek_Skylark]

On 4/25/2024 at 11:54 PM, 211 said:

Race Tech's spring calculator suggests I run a 0.40kg/mm spring rate. Stock rate is 0.42kg; so 0.02kg lighter. 

I'm not a professional, and 0.02kg/mm doesn't seem like enough to notice. In fact if I play with the calculator I can get it to spit out .42kg suggestion. I.e change my age  to "standard age- up to 29". 

Yeah, I'm also not sure about Race Tech calculator, it does seem to be on the "soft side" of guidance for the fork springs, shock springs seem to be somewhat in-line with at least WP recommendations. The funny thing is that the only other spring calculator I've used is K-Tech and theirs seems to be even more on the soft side for the forks. WP recommendations for forks is way stiffer (rate of two) than both RaceTech and K-Tech, it seems.

What do you guys think, at least for WP, that is, KTM group bikes that usually have guidance in their manuals, is it better to "baseline" spring rates based on the manual or Race Tech calculator? Which have you found to be "better"?

[Fun Police]

24 minutes ago, Radek_Skylark said:

Yeah, I'm also not sure about Race Tech calculator, it does seem to be on the "soft side" of guidance for the fork springs, shock springs seem to be somewhat in-line with at least WP recommendations. The funny thing is that the only other spring calculator I've used is K-Tech and theirs seems to be even more on the soft side for the forks. WP recommendations for forks is way stiffer (rate of two) than both RaceTech and K-Tech, it seems.

What do you guys think, at least for WP, that is, KTM group bikes that usually have guidance in their manuals, is it better to "baseline" spring rates based on the manual or Race Tech calculator? Which have you found to be "better"?

 

Racetech's calculator output varies widely depending on usage (type of riding) and the various 'prefers soft/hard/standard' and even the age input.

For 170lbs and 'singletrack/standard' I get at least two higher spring rates than what 211 is suggesting. For 'enduro', they tend to be biased high in the rear with light fork springs. The exact opposite for 'desert.'  All of these output stiffer spring suggestions for younger age.

 

So there's no right answer, it's just a product of their little program they've developed and which preset you think best matches what you do on your bike. That's why I give a side eye to anyone saying 'racetech's calculator is too stiff/soft'. It can be either.

[Radek_Skylark]

2 minutes ago, kidwoo said:

For 170lbs and 'singletrack/standard' I get at least two higher spring rates than what 211 is suggesting.

What is "211"? 🙂

To rephrase my question a bit - has anyone noticed trends with Race Tech calculators "guidance" with regards to suggestions for particular types of riding as compared to "real life experience" with customers/testing to conclude that some of the suggestions are "routinely" off?

[Fun Police]

4 minutes ago, Radek_Skylark said:

What is "211"? 🙂
 

 

 

 

[tom02cr250]

46 minutes ago, Radek_Skylark said:

What is "211"? 🙂

To rephrase my question a bit - has anyone noticed trends with Race Tech calculators "guidance" with regards to suggestions for particular types of riding as compared to "real life experience" with customers/testing to conclude that some of the suggestions are "routinely" off?

For KTM air fork spring conversions it seems they are on the stiff side for spring recommendations for a few of my buddies that I installed them for. For me they are on the soft side, but it all depends on what you select, and what you prefer. Have to use it as a suggestion, not the gospel, and try and test for yourself. 

[CaptainKnobby]

Just like Tom02cr250 stated. To me RT spring calculator seemed to soft for me. I tried a one rate higher and love it. I like a little firmer feel from the spring.

[Community Patrols-Manager]

The racetech calculator can be correct and can be misleading, it suggests for my weight and skill and terrain a 5.2, i have tested 5.3, 5.0, 4.8 and 4.6 all valved correctly and found 4.8 the best fit, that put the RT calculator off by 2 rates for me. Also note that as a rule lighter springs require more damping and stronger springs need less damping (compression) and the opposite for rebound (stored energy). There is also evidence that lighter springs with heavier damping produces the best result. Food for thought.

[211]

So I had an interesting experience my last ride out. 

My buddy with a '24 250 Beta Race just put springs in, front and rear. He's a bigger dude so he put in the heaviest springs Race Tech had to offer (iir, 5.4 or 5.8 in the front. not sure what the rear was, probably the heaviest they offer. he's ~250lb). 

At any rate, I rode it for a few trails on some pretty chundery loose rock singletrack and OMG it felt amazing.!

It felt like spreading warm butter over toast. So smooth!
 

Now...  at 175 street weight, I think those spring rates are too stiff for me, but I'm seriously considering going up in rates, by a lot. 
In fact I have in my cart a front .50kg and rear 5.8kg.

So ya, this confirmed what some of you were saying about heavier springs feeling better. It seems counter intuitive but I always thought you get your supple, high-speed compliance by staying deeper in the stroke; ie softer springs, or less preload. 

 

[Piney Woods]

Since the 70s I have always been told euros prefer soft springs/stiff valving and US guys prefer the opposite. That matches my preferred "feel".

[Fun Police]

1 hour ago, 211 said:

In fact I have in my cart a front .50kg and rear 5.8kg.

 

 

you may be overshooting a bit 😉

[211]

44 minutes ago, Fun Police said:

you may be overshooting a bit 😉

I thought the same thing this morning (after I bought them and selected next day shipping 🤦‍♂️).

But i'm about 200 with gear and these rates are right in there. If anything I could've gone one heavier if I was packing a lot of beers that day

 

Forks:

 

Shock

[Fun Police]

11 minutes ago, 211 said:

I thought the same thing this morning (after I bought them and selected next day shipping 🤦‍♂️).

But i'm about 200 with gear and these rates are right in there. If anything I could've gone one heavier if I was packing a lot of beers that day

 

Forks:

 

Shock

 

I don't ever feel bad about buying fork springs because you can always split them to get a lower rate between what you have and what you bought.

See what you think about the rear. With water bag etc, I'm probably pretty similar. Using a 5.3kg/5.2N on mine

Just measure check your sag. Going heavier on mine raised the bike enough that I ended up lowering it an inch.

[tom02cr250]

6 hours ago, 211 said:

So I had an interesting experience my last ride out. 

My buddy with a '24 250 Beta Race just put springs in, front and rear. He's a bigger dude so he put in the heaviest springs Race Tech had to offer (iir, 5.4 or 5.8 in the front. not sure what the rear was, probably the heaviest they offer. he's ~250lb). 

At any rate, I rode it for a few trails on some pretty chundery loose rock singletrack and OMG it felt amazing.!

It felt like spreading warm butter over toast. So smooth!
 

Now...  at 175 street weight, I think those spring rates are too stiff for me, but I'm seriously considering going up in rates, by a lot. 
In fact I have in my cart a front .50kg and rear 5.8kg.

So ya, this confirmed what some of you were saying about heavier springs feeling better. It seems counter intuitive but I always thought you get your supple, high-speed compliance by staying deeper in the stroke; ie softer springs, or less preload. 

 

I'm like 165 and often ride my buddies bikes and he's like 280-300 lbs and has obviously heavy springs. The front doesn't feel too too stiff for me, the rear usually feels decent, and I'm able to get comfortable on the bike and rip it good. They feel like they sit up real high to me cause of the stiff springs. And cause it's so much stiffer it allows me to hit stuff harder or faster. But all in all I prefer my bikes setup better, sprung and valved better for my weight. 

Edited May 7, 2024 by tom02cr250

[Community Patrols-Manager]

6 hours ago, 211 said:

I thought the same thing this morning (after I bought them and selected next day shipping 🤦‍♂️).

But i'm about 200 with gear and these rates are right in there. If anything I could've gone one heavier if I was packing a lot of beers that day

 

Forks:

 

Shock

The racetech calculator is one range to stiff for most people as they input themselves as B grade rider when they should enter novice so be aware of that mistake. I recently went from .50 to .48 in the fork and p65 to p60 in the shock and it is noticeable. With the lighter spring you can add a tad more damping in the shim stacks and gain better overall feel, especially highspeed 55mph+ 2-4" bump compliance. That has been my recent experience.