I think its time the mountain bike community should have a tuning framework for LSC. We have good frameworks for setting sag. But we should also have one for setting LSC.
Perhaps one already exists, if so, please share.
Currently, we have a language and framework for talking about and understanding sag. We know XC should have between 15% and 25% sag, AM 25% to 33%, FR/DH 30% - 40% etc
We say things like I used to run 30% sag, but when I tried 33% sag the bike felt more lively and everyone know what that means.
But when we talk about LSC, we hear things like I put the dial somewhere in the middle and I guess it feels okay. Which means nothing to anyone else, and usually very little to the person who said it.
LSC is a very important variable in how our bikes suspension performs, yet the average rider doesnt have a way to measure it, communicate it, or understand it meaningfully. I think this could change quite easily for the benefit of everyone.
Instead of only measuring sag (which is static), perhaps we should also be measuring dynamic sag or bounce sag. This would be defined as the percent your suspension compresses when youre bouncing on it as hard as you can in the parking lot.
Parking lot tune:
I know the parking lot tune gets a lot of flak from suspension geeks, and deservedly so because riders typically just look subjectively for what feels good to them, and what feels good in a parking lot may actually perform like dog crap on the trail and visa versa.
Further, I think its pretty common for a rider get their suspension to feel good to them in the parking lot, while not knowing that what feels good in the parking lot very well may under-perform on the trails, but they grow accustom to, and even fond of, their under-performing bike, and then a properly tuned bike that offers greater potential feels strange and undesirable to them. I either have done or am doing this myself. Im not suggesting a strict one size fits all, but I do think there are some tuning rules that maximize a bikes potential for everyone, even if it requires relearning what a your bike should feel like.
Moving on.
Im thinking the parking lot tune could be very useful if done correctly. Heres why: On the trail we have two pieces of equipment to absorb impacts: 1) our bike and 2) our body. How hard we can bounce the bike in the parking lot is indicative of our bodys ability to eccentrically absorb impact. Further, the bikes LSC should be tuned for a) the type of riding and 2) the individuals ability to absorb impact. Therefore, there exists a meaningful link between how a suspension will perform under a given rider and the percentage this rider can compress the suspension while bouncing in the parking lot (assuming proper spring and sag is already established).
For example, assuming you have the correct spring and sag, if you can blow through 95% of your travel by bouncing up and down in the parking lot, you have too little LSC. If you can use only 40% of your travel by bouncing up and down, then you clearly have too much LSC. But whats the correct/appropriate range of this bounce sag? (please dont say between 40% and 95%).
It seems like there could be some very good guide lines for tuning LSC according to this bounce sag. Maybe the guide lines are a little different for air vs coil (since air is progressive). Maybe the guide lines are a little different between DH, FR, AM, XC. Maybe the guide lines are a little different between platform and non-platform shocks. But it seems like some simple guide lines would easily help us get a starting point for setting LSC.
Just like proper spring sag settings, this is not intuitive or mathematically obvious. I dont think its as though an engineer sat down, opened a physics books and calculated that All Mountain riding would do best with 25% to 33% sag. Instead what happened was a bunch of pros and experts went riding over and over while trying a bunch of different spring settings and they just empirically figured out XC should have between 15% and 25% sag, AM 25% to 33%, FR/DH 30% - 40% etc. It seems to me the same type thing could/should happen with LSC; it just hasnt yet. Maybe its time for this happen and for LSC to get some proper love.
Unless youre an exceptionally experienced rider, its very difficult to notice things like your suspension sinking too much through a corner and therefore in need of additional LSC. But the pros and experts are out there tuning and optimizing their suspensions using a talent, experience, and feel that most of us just dont have. Personally, I would like to benefit from the experts experience just like we all have regarding spring sag. The good news is that the pros & experts LSC settings can be easily and objectively measured through bounce sag. But bounce sag has to first become a THING. Something we measure, talk about, compare, and review.
The best tuning advice Ive heard so far is 1) set sag 2) set maximum rebound without packing up 3) set just enough LSC to prevent mushy/wallowing feeling 4) increase HSC from min one click at a time to prevent bottom out as needed.
I still think the above is great tuning advice. (It makes far more sense than the overly literal approach minimum LSC setting for bump sensitivity and high HSC setting for big impact.)
However, I think mushing/wallowing is too vague and subjective. Perhaps LSC tuning should instead be expressed in terms of bounce sag as a percentage.
What do you all think? What's your bounce sag?
(Avy Rider, please chime in. I'd like to hear your thoughts).
If you got this far, thanks for reading!
Perhaps one already exists, if so, please share.
Currently, we have a language and framework for talking about and understanding sag. We know XC should have between 15% and 25% sag, AM 25% to 33%, FR/DH 30% - 40% etc
We say things like I used to run 30% sag, but when I tried 33% sag the bike felt more lively and everyone know what that means.
But when we talk about LSC, we hear things like I put the dial somewhere in the middle and I guess it feels okay. Which means nothing to anyone else, and usually very little to the person who said it.
LSC is a very important variable in how our bikes suspension performs, yet the average rider doesnt have a way to measure it, communicate it, or understand it meaningfully. I think this could change quite easily for the benefit of everyone.
Instead of only measuring sag (which is static), perhaps we should also be measuring dynamic sag or bounce sag. This would be defined as the percent your suspension compresses when youre bouncing on it as hard as you can in the parking lot.
Parking lot tune:
I know the parking lot tune gets a lot of flak from suspension geeks, and deservedly so because riders typically just look subjectively for what feels good to them, and what feels good in a parking lot may actually perform like dog crap on the trail and visa versa.
Further, I think its pretty common for a rider get their suspension to feel good to them in the parking lot, while not knowing that what feels good in the parking lot very well may under-perform on the trails, but they grow accustom to, and even fond of, their under-performing bike, and then a properly tuned bike that offers greater potential feels strange and undesirable to them. I either have done or am doing this myself. Im not suggesting a strict one size fits all, but I do think there are some tuning rules that maximize a bikes potential for everyone, even if it requires relearning what a your bike should feel like.
Moving on.
Im thinking the parking lot tune could be very useful if done correctly. Heres why: On the trail we have two pieces of equipment to absorb impacts: 1) our bike and 2) our body. How hard we can bounce the bike in the parking lot is indicative of our bodys ability to eccentrically absorb impact. Further, the bikes LSC should be tuned for a) the type of riding and 2) the individuals ability to absorb impact. Therefore, there exists a meaningful link between how a suspension will perform under a given rider and the percentage this rider can compress the suspension while bouncing in the parking lot (assuming proper spring and sag is already established).
For example, assuming you have the correct spring and sag, if you can blow through 95% of your travel by bouncing up and down in the parking lot, you have too little LSC. If you can use only 40% of your travel by bouncing up and down, then you clearly have too much LSC. But whats the correct/appropriate range of this bounce sag? (please dont say between 40% and 95%).
It seems like there could be some very good guide lines for tuning LSC according to this bounce sag. Maybe the guide lines are a little different for air vs coil (since air is progressive). Maybe the guide lines are a little different between DH, FR, AM, XC. Maybe the guide lines are a little different between platform and non-platform shocks. But it seems like some simple guide lines would easily help us get a starting point for setting LSC.
Just like proper spring sag settings, this is not intuitive or mathematically obvious. I dont think its as though an engineer sat down, opened a physics books and calculated that All Mountain riding would do best with 25% to 33% sag. Instead what happened was a bunch of pros and experts went riding over and over while trying a bunch of different spring settings and they just empirically figured out XC should have between 15% and 25% sag, AM 25% to 33%, FR/DH 30% - 40% etc. It seems to me the same type thing could/should happen with LSC; it just hasnt yet. Maybe its time for this happen and for LSC to get some proper love.
Unless youre an exceptionally experienced rider, its very difficult to notice things like your suspension sinking too much through a corner and therefore in need of additional LSC. But the pros and experts are out there tuning and optimizing their suspensions using a talent, experience, and feel that most of us just dont have. Personally, I would like to benefit from the experts experience just like we all have regarding spring sag. The good news is that the pros & experts LSC settings can be easily and objectively measured through bounce sag. But bounce sag has to first become a THING. Something we measure, talk about, compare, and review.
The best tuning advice Ive heard so far is 1) set sag 2) set maximum rebound without packing up 3) set just enough LSC to prevent mushy/wallowing feeling 4) increase HSC from min one click at a time to prevent bottom out as needed.
I still think the above is great tuning advice. (It makes far more sense than the overly literal approach minimum LSC setting for bump sensitivity and high HSC setting for big impact.)
However, I think mushing/wallowing is too vague and subjective. Perhaps LSC tuning should instead be expressed in terms of bounce sag as a percentage.
What do you all think? What's your bounce sag?
(Avy Rider, please chime in. I'd like to hear your thoughts).
If you got this far, thanks for reading!