Dull but…

Currently on 5/8, (8 being max spacer/min volume). Sag set at 20%, a bit above recommended pressure. Travel set at 140mm, 3psi more in the neg chamber. Still bottomed on a small drop into a berm. So more spacer…

How much spacer is too much spacer? (9/8, obvs) Is 3/4 spacerage fairly standard, or sign that I’m doing something iffy somewhere else? Not riding anything supergranly – Surrey Hills and occasional Rogate, mainly.

Obviously the right answer is try it and see. Just curious as to what’s “normal”. Am I normal?

Define small drop…

If you’re bottoming on “small” drop you either need lower volume or higher pressure.

“ Still bottomed on a small drop into a berm”

Smooth transition or huck to flat? How small?

It’s probably 3-4 lip to landing, but you’re straight into a steep, tight, flat-ish catch berm. it’s pretty harsh, there’s plenty of bigger stuff, bigger jumps around but with much nicer landings. But that’s doesn’t really matter.

Point is, I bottomed out on something I don’t think I should be bottoming out on. Air is set to about where it should be, apparently, so spacers is next.

Is 3/4 of max spacers the kind of thing a lot of people end up doing? There aren’t a ton of reviews out there on the helm, most mention pressure settings, adjustment clicks made from open/closed, all mention the spacer adjust, most had a play, but no-one says where they ended up with the spacer thinger.

Just curious. and nowhere to go but STW*. I’m so ronery…

*and my shed, the toolbox, the forks and then the trails.

The 3psi extra in the -ve chamber will be making a lot of difference. Mine felt very wallowy when I tried similar.

27.5 or 29 and Helm 1 or 2?

As you shorten the fork travel, the negative chamber gets disproportionately bigger compared to the positive, so it’ll have more effect and make the fork linear. The Helm 2 comes with 2 different volume travel adjust spacers to try and compensate for some of this.

For me on a 160mm 29” H2, I’m running 50psi, second notch of volume from the top and minimal damping. The last 15mm of travel is usable, but it’s for the big stuff and saving mistakes!

50psi? Don’t they recommend your kg in psi or half your weight in pounds as a starting point?

Are you very light, or has the mk2 changed that much?

Mine’s a Mk1 29er.

Assumeme you mean 2nd notch from the to of the fork?

No idea what they recommend. I’m 64kg and that’s about 30% sag. Although that in itself is a pretty fluid target on a LLS bike. I find 2 or 3 psi can make a big difference in how the fork feels, but no measurable change in the sag.

2nd notch from the top, yes. A few of the lighter guys I ride with have removed the doo-dad altogether as they can’t bottom out otherwise. (less of an issue on the H2 as the damper oil is lighter)

I do find you need to rebalance the +ve and -ve chambers every ride, or they start to suck down which makes them more linear – and make sure you’re pushing the front wheel away from the crown while you’re pushing the air balance button on the bottom of the leg, or again it will suck down.

In terms of difference between H1 and H2 – there’s not much change in the air spring. The big difference is that the lower seal head on the 2 is held in with a circlip, rather than it screwing in to the stanchion. (apparently overtightening could flare the bottom of the stanchion, leading to a sticky fork). The other change was the large volume travel adjust spacers I mentioned in the original post.

Also consider adding some HSC – that’ll make it harder to use all the travel. To determine how far you go into the travel on bigger hits, more psi, more volume spacers and more HSC will increase the force needed to move the fork fast deep into the travel. Spacers will only affect the end stroke. Psi will stiffen the whole travel. HSC will only stiffen it under quick/big hits. It’s a juggling act!

Cheers guys, I’ll revisit the other bits before I go for more spacing, then. Never had a fork with this much adjustment before. I’m 70kgs, got 73psi and 76 in negative – on advice (2nd hand) from Cane Creek to keep the travel supple for the first third. The frame’s designed around 130mm, but I’ve bumped it to 140mm to off-set the suck-down from more -ve. Sag’s at 20%. Thought the idea was to go to volume spacers if you’re bottoming out when sag’s correct, which is why I’ve ended up where I have. I’ll try 75/76 or something.

Cheers again!

If everything else feels perfect but you’re bottoming out too soon, add a volume spacer, don’t increase the psi. I’d definitely start there.

The shorter the travel, the more volume spacers you need (which is why a Pike or Lyrik at max travel comes from the factory with no spacers in but at minimum travel it comes from the factory with about 5 spacers in!)

The trick for keeping travel supple is to drop down to 2.5wt oil in the damper. (this was the biggest performance change between H1 & H2)

Don’t try running more air in the -ve chamber – especially with the fork reduced in travel as the -ve spring is already quite large proportionately.

(I spent a month last summer working at Cotic – they’ve sold a LOT of Helms and are on really good terms with Cane Creek so have a lot of knowledge. It was also the point where we were clearing out the H1 stock and getting the first few batches of H2 in, so could see the differences. I also ran a pair of ex-demo bike H1s for a couple of months until my H2s turned up.)

Running Helm 1 at 160mm on my Rocket. Also running significantly lower than the ‘recommended’ pressure – 78kg and 60psi for about 30% sag. Running minimal damping and maximum volume (minimum spacers). Same experience as JonEdwards (on a LLS bike) in that changing the pressure even 5psi each way has minimal impact on measurable sag, but a massive impact on feel. I tried the extra neg pressure and it does make it lovely and supple but too linear and blowing through travel on medium hits too much for me. Would also echo the points about re-equalising the pressure regularly, with a good pull to extend the fork while you’re doing (helps to do it with someone else).

Ha! Brilliant, thank you, Jon!

I’d seen Cotic had specced them a lot, and I’d been thinking about getting in touch. Got the chambers level at 80psi now, that gets me to 35% sag with my arms locked over the bars and toes dangling. – as per some chap on the internet:https://www.youtube.com/watch?v=4qunOrD9p-E

I thought I’d go looking for hardtail specific advice, as one person’s “standing on the pedals” is another person’s “attack position” is someone else’s “balanced over pedals and bars”

Seems odd that it’s so much higher than your two. Is that explained by my 5/8 on the volume reduction? I’d have that it would be the other way round, with lower volume ramping up quicker?

2.5wt oil in the damper

Do you mean 2.5wt oil in the damper lower, or in the cartridge itself?

with a good pull to extend the fork while you’re doing

Yup, doing this. ta!

“ Got the chambers level at 80psi now, that gets me to 35% sag with my arms locked over the bars and toes dangling.”

This is a really weird way to set sag. Totally ignores weight distribution due to wheelbase and front/rear centre.

“I thought I’d go looking for hardtail specific advice, as one person’s “standing on the pedals” is another person’s “attack position” is someone else’s “balanced over pedals and bars””

Weightless bars, standing with all your weight on the pedals, elbow against/near a wall so you don’t fall over, weight the bars a bit and bounce a few times, unweight the bars, let it settle, push the o-ring down. Then sit on the dropped saddle, step off gently and measure. Do it a few times and take the average because of friction/stiction. May be more complicated but it works.

But that way also ignores weight distribution. If I’ve got a really long hardtail, that method won’t be putting much weight through the fork at all. Plus, are your hands on the bars? Are your bars higher than mine?

I like that^ chaps method, because it takes all of those variables out of it. And if you’re riding steep and/or tech, a you’re going to be using the suspension most when most of your weight is going through it.

And anyway, it’s a starting point, not a hard rule to stick to for ever. I know I’ve started in the right place according to that method, and I’ll go from here.

“ But that way also ignores weight distribution. If I’ve got a really long hardtail, that method won’t be putting much weight through the fork at all.”

His method puts essentially all his weight through the fork. If you stand on your pedals and balance properly then the weight proportion through the fork is chainstay length / wheelbase and vice versa through the rear.

“Plus, are your hands on the bars? Are your bars higher than mine?””

It doesn’t matter where your bars are if you’re putting all your weight through the pedals and thus the BB.

Sorry, I think I misunderstood your method. The way you explained it made it sound like after resetting the o-ring, you set the sag by being sat on the saddle.

Still, almost everyone else recommends setting sag in a riding or descending position, so your method must mean you have to set sag at a lower level than the usual in order to arrive at a similar starting point?

Or are you saying most people run pressures too hard because they set sag with the bars partly weighted?

Well, I went for radge yesterday with the 80psi in, and it was pretty good. Definitely noticed it riding higher, which will take a little adjusting to. Pretty much bottomed out on something in definite bottom-out territory. Felt nice and supportive, too. Wasn’t on top riding form due to late decision involving gin the previous evening.

80psi = 35% sag according to that chap in the vid – all weight on bars
16% sag according to cheifgg – all weight on pedals
23% sag according to cane Creek – “normal descending ride position”. The 80psi is exactly the “half your weight in lbs” they suggest you start with. Don’t know why I was fixed with the idea that 72 was right to start with – duff advice from a shockwiz, or setting sag with not enough weight on the bars. No idea!

TLDR: Thanks for pointing me back to air pressure.

duff advice from a shockwiz, or setting sag with not enough weight on the bars. No idea!

That’s where you went wrong, shockwiz doesn’t work with the Helm fork. I thought about renting one to help understand mine when it was new and it specifically stated in the website it wouldn’t work with any fork you can manually adjust the negative chamber, wouldn’t fit on my IL shock either!

FYI I’m running the same as Jonathan, 160mm fork on a Rocket. I weigh 79kg and have 60psi positive and 62 negative, one click of slow compression and fully open high. Rebound is 4 clicks from fastest with the volume spacer at maximum but the adjuster still in there. Buttery smooth and can soak up 4-6ft drops using all the travel with no harshness whatsoever. I like my forks active and it’s great at that.

One thing to keep in mind is that mine was much more supple after a few rides then a lowers service, loosened it up lovely.

That’s where you went wrong, shockwiz doesn’t work with the Helm fork.

Ha! That’s not a surprise! The LBS lent me one for free, so I didn’t do much reading around. It only connected to my phone half the time, would disconnect most runs and tell me there’d been “no extreme travel events” when I’d bottomed out hard. I’m pretty sure I didn’t take any notice of it, to be honest!

Still a bit confused as to why I need so much more pressure than you guys, when I’m not as heavy? 72kgs in kit.

80psi, 2 HSC, 2 LSC, 3 rebound, 5/8 click taken up of the volume reduction. 140mm travel, just serviced lowers. But did that before found out about the 2.5wt oil on the damper side from Jon above!

Sounds like I’m setting up a different fork to the Jons and reluctantjumper?

Biggest difference is the travel with mine at 140mm, but less air volume would mean a greater ramp up for the same starting pressure wouldn’t it, as that’s the point of volume reducers.

“ Biggest difference is the travel with mine at 140mm, but less air volume would mean a greater ramp up for the same starting pressure wouldn’t it, as that’s the point of volume reducers.”

The spring curve on an air fork is like a j shape. Starts higher, drops lower, then starts ramping up more and more. When you swap to shorter travel on most modern forks you just cut off the later part of the j where the spring is ramping up more and more. I found it quite hard to get a Pike 27.5 feeling good at 130 but much easier at 150. I also found a Luftkappe (increased negative volume, decreased positive volume) worked well at 150 but ramped up too hard at 160.

When you swap to shorter travel on most modern forks you just cut off the later part of the j where the spring is ramping up more and more.

This is what I was trying to figure out. The travel reduction is in the damper side, so do you have the same volume air chamber for every travel option?

JonE suggests not above when he talks about the proportion of neg to positive changing with volume reduction. And the Helm is a 170mm fork that can be reduced to 100mm with spacers. Surely the fork set up at 100mm isn’t bottoming out at 10/17ths of the air volume? Can’t be right, can it? That would be rubbish!

The shock wiz would work fine on the Helm fork.