Mechanics Quick Question Thread [Ask Questions Here]

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Mechanics Quick Question Thread [Ask Questions Here]
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Posted: Oct 1, 2022 at 16:45 Quote
Ah, yeah I see that. 46od and 12t

Posted: Oct 1, 2022 at 22:38 Quote
I am having some trouble calculating spring rate for a coil rear shock. I have tried out a bunch of different online calculators and I was getting anywhere from a 400 spring rate all the way up to 550. I weight about 140lbs kitted up. The bike that I may put a coil shock on Is my Evil Following. It has shorter travel and a fairly high leverage curve which I understand usually means running a bit higher sag closer to 30%. By far the MRP calculator was the most in-depth in the data it wanted you to enter and It gave me 550 for my recommended spring rate. That seems very high for my body weight. Can anyone here comment on what spring rate would be best for my weight and comment on what spring rate you are using for your body weight? Thanks!

Posted: Oct 2, 2022 at 2:18 Quote
Lion1 wrote:
I am having some trouble calculating spring rate for a coil rear shock. I have tried out a bunch of different online calculators and I was getting anywhere from a 400 spring rate all the way up to 550. I weight about 140lbs kitted up. The bike that I may put a coil shock on Is my Evil Following. It has shorter travel and a fairly high leverage curve which I understand usually means running a bit higher sag closer to 30%. By far the MRP calculator was the most in-depth in the data it wanted you to enter and It gave me 550 for my recommended spring rate. That seems very high for my body weight. Can anyone here comment on what spring rate would be best for my weight and comment on what spring rate you are using for your body weight? Thanks!

High average leverage doesn't really require more sag. It does mean you will need to run a harder than average spring to achieve the same sag as if your bike had a lower average leverage. The shock will also require harder damping settings to suit. Sag however should be treated normally. The following isn't particularly high leverage though, it is quite progressive though.

High progression leverage curves (the lever rate reduces throughout the stroke) do often work well with more sag, as the rate ramps up enough at the end to still provide good support even with larger sag numbers. This depends on the exact shape of the curve though. The earlier in the stroke that the rate drops off, the more sag you can get away with.

I had a 2 min google search and didnt see any graphs for the following. They do suggest running more sag, so I assume its quite progressive. I'd suggest a 500lb spring should give about 30% sag, but ive totally guessed at the amount of progression and the shape of the curve, so could be way off... i do think stuff down at the 400 end of the range probably will be too soft though.

This is the inherent problem with really interestingly shaped lever curves, theyre very hard to predict as small changes can have big effects. I'd suggest trying a 500, but be prepared for it to be wrong and having to be changed. Is there a local shop you can go to with your bike who might let you do a quick sag check after purchasing?

Posted: Oct 2, 2022 at 9:43 Quote
Any particular reason why adjustment clicks dissapears after a shock service?

Posted: Oct 2, 2022 at 14:00 Quote
Anyone had any experience with Fox40 Performance fork that is noisy? It seems like the bushings are too wide. Never heard about to loose on a rather new fork, only to tight bushings. But this one seems to have the lower rocking back and forth a tad.

It actually most noticeable when you got the bike upright like for putting in a lift and then bounce on the rear wheel or roll it of a step with the bike in that vertical position. It rattles similar like a loose coil. But that wasn't the source...

This is a '22 fork used about 12x a half-day (3 or 4hr liftpass) for DH, so prob less then 12 running hours.

O+
Posted: Oct 2, 2022 at 16:04 Quote
Noeserd wrote:
Any particular reason why adjustment clicks dissapears after a shock service?

They might have lost your tiny detent ball?

Posted: Oct 2, 2022 at 16:42 Quote
I would like some help with suspension recomendations. If you guys could please just throw numbers at me involving PSI for both front and rear, amount of volume reducers, and compression and rebound adjustments. Basically I feel like my suspension isn't great and I feel like I would like to restart by trying what some of you guys would recommend for my body weight and suspension. I weight about 140-145lbs with gear on and my suspension is a 130mm Pike Ultimate and my rear shock is a Rockshox Deluxe Ultimate. My current for setup for my fork is 48 Psi with either 2 or 3 volume reduces (I can't quite remember) and my compression settings is 2 clicks of HS and 4-5 clicks of LS. My rear shock setup is 159 psi running 2 of the 1T volume tokens and a gnar dog token which is 2.5 which combines is the max the rear shock can run. Any setups for me to try would be appreciated greatly!

Posted: Oct 2, 2022 at 16:54 Quote
Lion1 wrote:
Basically I feel like my suspension isn't great

Without specifics of what you find not great about it, any suggestions you get may be worthless.

Posted: Oct 2, 2022 at 16:55 Quote
hey I have a RockShox coil on a fox shock it has some slop.... is that ok to run?

Posted: Oct 2, 2022 at 16:57 Quote
Lion1 wrote:
I would like some help with suspension recomendations. If you guys could please just throw numbers at me involving PSI for both front and rear, amount of volume reducers, and compression and rebound adjustments. Basically I feel like my suspension isn't great and I feel like I would like to restart by trying what some of you guys would recommend for my body weight and suspension. I weight about 140-145lbs with gear on and my suspension is a 130mm Pike Ultimate and my rear shock is a Rockshox Deluxe Ultimate. My current for setup for my fork is 48 Psi with either 2 or 3 volume reduces (I can't quite remember) and my compression settings is 2 clicks of HS and 4-5 clicks of LS. My rear shock setup is 159 psi running 2 of the 1T volume tokens and a gnar dog token which is 2.5 which combines is the max the rear shock can run. Any setups for me to try would be appreciated greatly!

Watch these 2 videos, they will help tremendously to understand your suspension better, not the same brand but the concept is same more or less

https://youtu.be/GPQnjSe6rdw?t=316

https://www.youtube.com/watch?v=CM0lDN80miQ

also yeah some input on whats the thing feeling bad right now would be good

Posted: Oct 2, 2022 at 17:01 Quote
brady7brady wrote:
hey I have a RockShox coil on a fox shock it has some slop.... is that ok to run?

it doesn't seem to affect anything but I have no idea. if its just cosmetic that's fine but if the sags gunna mess up the shock id wanna know

Posted: Oct 2, 2022 at 19:15 Quote
barp wrote:
Lion1 wrote:
Basically I feel like my suspension isn't great

Without specifics of what you find not great about it, any suggestions you get may be worthless.

I feel like for the rear my rear shock skips across the ground more than absorbing the bumps. By running max volume tokens it prevents me from bottoming out on the bigger features but even with not super high air pressure I feel like I cannot adjust the compression enough to get it to feel supple. The rear shock only has a - + and neutral setting. Nearly the same thing applies to the fork. I run 3 volume tokens to make to fork feel progressive so I can compress the fork to pump and gain speed. I am running enough pressure so that I do not bottom out but even with compression nearly open on both the HS and LS I feel that the fork is too harsh. Both the rear shock and fork have been serviced recently.

Posted: Oct 2, 2022 at 19:22 Quote
What are your rebound damping settings? Sounds like you may be "packing down" under excess rebound damping.

Posted: Oct 2, 2022 at 20:38 Quote
I was running fairly slow rebound so I will change it to faster. I started trying educated guesses of compression, rebound, pressure etc and It seems very apparent that suspension does not feel anything like how it feels in the parking lot compared to on the trail. I seem to have gotten it better just by fiddling with it and it definitely feels stiff in the parking lot but feels pretty good on the trail

O+
Posted: Oct 2, 2022 at 20:58 Quote
https://trailhead.rockshox.com/en/search/

You can use the rockshox setup guide to help to get you back to a starting point and then experiment from there


 
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