From personal experience, having the same complaints and looking for the same qualities, I found the solution in the Vorsprung Smashpot coil conversion. Yes, you indicated you care more about weight than the final fork performance, but I'm telling you anyway. I had the same concerns but finally put comfort and performance ahead of bike weight. I would never go back.

 

The reason I don't want to go coil now is because my weight is changing as I'm working to drop another 5-10 lbs. Since rider weight determines spring weight I want something that will be adjustable for the time being. I may end up with a coil in the future once my weight is stabilized.
I'm not afraid of the weight of a coil.

 

I'd do the runt. Midstroke support is exceptional. I've got one in my 34 and 38 and have run one in a 36 as well. It's well worth the $200.

 

Vorsprung has several solutions. 2 add negative volume and 1 is a coil. Can’t say enough good things about their products.

 

I've been chasing around the performance of my fork. It's a fox 36 rhythm. Mainly I've been searching for a bit better small bump compliance trying to keep my hands from going numb. After a teardown and rebuild to make sure everything was lubed properly (it wasn't) I'm 95% satisfied.

The issue I'm chasing now is that with the setup I'm on now, the fork has a bit more dive under braking than I'd like.

I'm about 170 lbs with gear on.
I'm running 78psi with compression damping full open, rebound at 6 clicks from closed and no volume spacers.

I've tried one volume spacer at 78 psi, and that felt a little more harsh but had less dive.

I was down at 75 psi with one spacer before the rebuild, but once the fork was moving better after rebuilding that was way too soft.

I'm a little hesitant to increase the compression damping since it may compromise the small bump performance and also the grip damper doesn't have detents so fine adjustments are less repeatable than I'd like.

Any suggestions for tuning before I throw parts at it or replace the fork. I'm not interested in converting to a coil since I'm still working to get lose another 5 lbs so I'd like the ability to fine tune once I get down to my goal weight of 160 w/o gear.

I'm considering a DSD runt or a grip 2 damper to address the dive.

Thoughts?
Thanks in advance.

A few things to try before you start throwing parts at the fork:

1) Handlebars- What are you running? An overly stiff set of bars will cause hand numbness. I once spent two years and two forks trying to get a bike to stop making my hands go numb. Turns out it was the bars, an early set of Answer Protaper carbon bars that were super stiff. They were so bad, I threw them on a friend's bike that notices nothing and he came back complaining something was wrong on his bike. Gave them to someone else, they came back. Finally gave them to someone for a DJ bike. Personally, I find the Ibis carbon and Enve M6 bars to have a good ride quality.
2) Grips- Have you played with different grips? Different grips work better for different people. Hand size and grip size have no correlation, there are people with small hands that find large grips work well and vice versa.
3) Rebound- Have you tried taking 2 clicks of rebound out and seeing how it feels? Too much rebound will lead to the fork packing and being in the ramp up portion of the spring curve, which will cause harshness.
4) Air Pressure- Have you tried increasing the pressure 5 psi? It is counterintuitive, but this is the other side of the coin from too much rebound. Too low of a pressure will lead to the fork sitting in the sag at the point where the spring curve is steep and cause harshness. Fox forks seem more sensitive to this than other forks.

None of the above working, I would try the DSD Runt. I don't think a Grip2 is going to accomplish what you are after.

 

I'm running one up carbon bars and do feel like they helped out with my hands. I tried raceface carbon bars before these.

For grips I'm running ergon GA2 Fat grips. I tried PMW grips, and a couple others first.

Rebound I've gone back and forth between 6 and 8 clicks open. 8 feels like the front loses a little traction in bumps. I could probably run with either 6 or 7 clicks open. I think 6 feels a little easier on the hands and a little more balanced with the rear of the bike which is why I ended up there. I don't think the fork is packing down, but could be wrong.

With pressure, I started at 80 psi after the rebuild and dropped down to 78 after a few rides. 78psi gets me just over 20% sag.

 

A coil spring is the best solution for plush off the top and more support in the middle. Can't beat it.

5lbs of body weight won't make much difference. I fluctate by that much over a big day in the saddle.

 

Since it's cheap (potentially free) and easy to do, as well as easily reversible, why not add a stack of volume reducers and then fine tune your pressure accordingly?

 

The fork came with 3 volume reducers. I rode it that way for a while and never used more than 100mm of travel. And the fork always felt harsh and didn't smooth out small bumps well at all. after pulling it apart I'm sure the excess grease was not letting the negative chamber equalize properly. I dropped to 1 volume spacer before rebuilding the fork. After rebuilding the fork I have tried 0 and 1 with pressure between 77 and 80 psi.

I find the best overall feeling with 0 reducers at 78 psi but would like to limit the brake dive. 1 spacer at the same pressure limits dive a bit more but feels more harsh in my hands. I don't bottom out on either setup on most rides.

 

Under what conditions do your hands go numb?

 

Mainly on rolling technical terrain, lots of roots and rocks but not super steep big climbs or descents. Technical blue to moderate black trails. I'm quick enough to keep up with a couple of buddies on ebikes but I don't know how fast I really am at this point.
On longer climbs I change my hand position up and can keep it at bay.

I'm in GA and ride mainly at Allatoona Creek park (luckily right out my back door about 20 yards) and Blankets Creek.

 

Do you notice it on steep downs also? Or just on technical rolling terrain? What bike is it on? Have you had this issue before on other bikes? What bike were you riding before and did you have the issue.

I am wondering if some of it comes down to bike fit. i.e. Steeper seat tube angle puts more weight on your hands when sitting on rolling terrain. Steep SA work really well for straight up and down, but can be less ideal in rolling terrain depending on your body proportions.

 

Do you notice it on steep downs also? Or just on technical rolling terrain?

I don't notice it on steep downs. I don't feel like bigger compressions are the problem, but more of the repeated smaller hits that bother my hands. The brake dive I mainly notice on braking into switchbacks and tight turns.

 

I weight 175 and run mine at 85 psi with no tokens. Like someone said earlier it seems counterintuitive to add more psi but it actually made a big difference for me. Small bump is good, no brake dive and plenty of mid stroke support.

 

Can't hurt to try higher pressure out.

 

Brake dive can be fixed with more pressure or with low speed compression. My fox 34 grip2s seem to run better with more pressure. With my Mezzer I was able to dial in low speed to help with brake dive.

I don't think it's only the fork, I think it's also your riding position. I would try messing with spacers under the stem and saddle setback (i.e. slide the seat away from the handlebars on the rails). Those changes have been key to keeping my hands happy on rolling technical terrain.

 

I dropped the stem down one spacer (5mm iirc) and have the seat back a bit already to get more comfortable on the bike.

 

I'm a little hesitant to increase the compression damping since it may compromise the small bump performance and also the grip damper doesn't have detents so fine adjustments are less repeatable than I'd like.

How do you know it will compromise small bump performance? Did you try it? Yes they don't have detents but you can at least test in 1/8 turns to get a proper feel for where the damping is at.

Depending on year, the shims are often free to flap around if the adjuster is too far open, so closing the adjuster enough to secure them again can make a world of difference

I'm considering a DSD runt or a grip 2 damper to address the dive.

Vorsprung Secus is a much better spring upgrade, and would be my top suggestion. Grip 2 will be a little better but I would do that second

You mentioned tyres, pressure looks ok, but have you tried lower? What width are they and what type of terrain do you ride? If it is especially rough, rocky or fast you may need a beefier casing with lower pressures

 

How do you know it will compromise small bump performance? Did you try it? Yes they don't have detents but you can at least test in 1/8 turns to get a proper feel for where the damping is at.

Depending on year, the shims are often free to flap around if the adjuster is too far open, so closing the adjuster enough to secure them again can make a world of difference


Vorsprung Secus is a much better spring upgrade, and would be my top suggestion. Grip 2 will be a little better but I would do that second

You mentioned tyres, pressure looks ok, but have you tried lower? What width are they and what type of terrain do you ride? If it is especially rough, rocky or fast you may need a beefier casing with lower pressures

I don't know that adding compression will compromise the sensitivity, but that's my concern. I dislike the imprecise nature of not having detents, but that's just me being a little ocd. If I give the compression adjuster a quarter turn it makes a big difference just in the garage.
Really I should try this out and see if I can dial it in.

Tires are 2.5 front 2.4 rear. I have not tried lower than 20/23 psi. Primary terrain is rooty and rocky.

Why do you say the Secus is a better spring upgrade?

 

The problem is the damper. At fully open you've got no LSC and only some HSC from the base-valve and the mid-valve is trying to do everything.

I've had good results tuning these but they're very fiddly as they're very sensitive to stack preload. Like 0.05mm makes a big difference sensitive.

 

This was the thought process I had for upgrading to a grip2 damper. To gain separate high and low speed compression adjustability. That way I could add a touch of low speed compression damping more precisely.
Talking 0.05 mm is right in my world, that size variation will kill any part I deal with in my day job.

 

dang it, wrong button

 

Here are my thoughts so far based on everything.
1. Try more compression damping with my current settings, this is the easiest to try and easiest to change on the trail.
2. Try more pressure. Bump up pressure to 80psi, I've run 80 before and thought 78 felt better.

Those are the things to try out before throwing parts at it or replacing the shock.

 

You can always mark the LSC dial position on the fork upper using a marker, or marker on a piece of helicopter tape if you don't want to mark the fork itself.

Also, the main parameter affecting brake dive is the air spring. Compression slows the rate of the dive but often we're on the brakes long enough that the fork still compresses to around the same point. Adding compression is definitely worth a shot but view it as a fine tuning tool. Your main focus should probably be spring rate though.

 

Silver sharpie is the plan

 

Fwiw I have noticed the rhythm fork performs better at 15% sag and lsc dial 1/8-1/4 closed. I personally think you are starting too far into the travel at 30%. Again, I am 175 and I run 85 psi in mine with no tokens. Lower psi gave me the same kinda harsh feeling over consecutive small bumps.

 

This. On the Rhythm on my son’s bike I had it at 85 psi when I first rode it and it was harsh and dove a bit. 95psi and it was a different fork, much better.

@nothtatbrian I would try 85psi in the front, as everything else in your setup looks dialed in. Play with the higher pressure before for the compression.

 

I upped the pressure to 85 tonight to prep for a ride tomorrow. I'll see how it goes and post results tomorrow.

Thank you everyone for the input.

 

With regards to tires I'll likely play with pressures a little more once the leafs clear off of the trails a little. They really came down here in the last couple of weeks and it's making things a bit less predictable and more slick with the leaf cover. Everything feels a little squirmy right now.

My plan is to play with 1/8 turn of compression tomorrow on a few laps.

 

So after riding today,

85 psi in the fork is definitely going to be my new base setting. Everything else the same 0 volume reducers, rebound 6 clicks open, compression full open (I did play with 1/8 turn closed over a couple of sections).
I used 75% of the travel compared to 80% the last time I rode this route. Not surprising, this felt balanced front and rear and it's not a ride that should be bottoming out.

There is a little more chatter making it through to my hands but it wasn't harsh.
I still fought some tingling in my hands, but never full numbness. Pretty much similar to how my hands felt with 78 psi, certainly not worse.

The brake dive was much better and the front end doesn't drop under braking. Much better.

I did play with an 1/8 turn on the compression and can feel the difference on some sections. A little more sharpness to smaller bumps, I noticed it most definitively on a gravel section. It is less noticeable on rooty / rocky singletrack sections. I'll probably leave it open for most sections.

Thanks you everyone for the advice.

Happy Thanksgiving.

 

Step 1) Buy Marzocchi Bomber Z1 coil kit + coil
2) open up your fork
3) remove air shaft
4) insert coil

4) enjoy great small-bump sensitivity and mid-stroke support.

I've had the exact same problem on my 36 Rhythm : If I increased the air pressure or added compression to have mid -stroke support, it would feel harsh on brake bumps etc.
If I dropped the pressure and/or opened up the damper fully I would have the sensitivity I needed but not the mid-stroke support. Coil solved both of these problems

 

The Luft Fusion air spring provides all the sensitivity and support you can imagine and it's more adjustable and cheaper then coil.