Well it’s official – I now have cunning suspension!
First observation is that the shock absorbers and springs are a LOT cleaner than the rest of the car, but I’m working on fixing that…
So how did I get to this point?
I opted for the non-adjustable Bilstein suspension (AKA standard suspension) when I spec’d the car. I explained to the good people in Crewkerne that I will mostly be doing A and B roads, so the standard suspension was deemed a good fit.
And by and large, it was! It crashed a bit over potholes and speed bumps, but on tight twisty B roads, it did a much better job of keeping everything in check. My problem became one of not being able to adjust it for different scenarios. It was too firm when trying to get air over a speed bump and too soft when trying to keep up with Atoms on relatively smooth B Roads.
So after months of agonising, here I am with Fox’s solution.
Why Fox???
Well my main issue with the Bilstein (adjustable damping or not) was the tightly wound tender spring. Under fast compression, they slapped together quite violently (my Nomad is probably heavier than most) which was not only annoying, but also sent jolts through the steering. From looking at pictures, the Ohlin tender spring is not as tightly wound, but to me, appear ‘more tender’. I had heard reports from others going off-road that the Ohlin suspension can be ‘crashy’. Oh, and it was very expensive.
- Tender spring comparison.jpg (295.93 KiB) Viewed 2368 times
The issue with Fox though was that they were designed primarily for off-road and didn’t have the ability to be ‘firmed right up’ if needed to be. Then, a new Fox solution was introduced by Crewkerne earlier this year. A newer shock absorber that can be ‘wound right up’ if need be. In fact, I was told that the newer Fox set-up could be considered for track use. This seemed to be an option that could span off-roading or chasing Atoms (with adjustment), as well as the spirited blast to Sainsbury’s when you’re running low on cous-cous and need an excuse to get out for an hour or two.
So what do I think???
Rubbish!
I did a 150-mile trek over fast A and twisty B roads on the day of collection and was quite unhappy. Don’t get me wrong, the rears were great. I immediately felt better traction being put down and when the back did go, it felt a lot more predictable. The fronts though… Jumpy and unsettled at 60MpH+ and hard braking and sharp cornering caused all sorts of metallic crunching through the steering. It was as if the springs were not seated properly and any movement caused them to twerk about looking for somewhere to settle in the mounts. So after another 120 mile trip home on Sunday morning, I brewed up and did some tinkering.
First off… The main and tender spring are coupled together in a ‘floating seat’. By this, I mean they are not locked in position on the damper, but can travel together as a single unit until the tender spring starts to force the main spring to start compressing. All well and good, but… There is also a lockout ring that will retard the travel of the tender spring and force the main spring to kick in. That travel is set to 5mm by the factory for road use. 5mm of travel is not a lot. In fact, it may as well be a fixed spring set up. At least in a fixed spring set-up, the tender spring doesn’t ‘bottom out’ just as momentum is starting to build.
I noted that the advice from Crewkerne for off-road settings is to essentially ‘get rid’ of the tender spring lockout ring by winding it right up and allow full travel of the dual-spring set-up, so I did just that. No more sudden changes of compression rate, just progressive spring compression over a wider range of travel.
BEFORE AND AFTER
- Lockout ring - before and after.jpg (356.5 KiB) Viewed 2368 times
Next up was the compression and rebound settings. The Fox shock absorbers have 3 settings: High Speed Compression; Low Speed Compression; Rebound. They also feature a hydraulic bump stop promising it will never bottom out.
My understanding is:
- HIgh Speed Compression: Large bumps and dips in the surface / landing from jumps; needing softer settings and a fair amount of spring travel to absorb movement
- Low Speed Compression: Steering, acceleration, braking changes / smaller imperfections at speed; needing firmer settings to lessen spring travel to counteract movement
- Rebound: How quickly a shock absorber returns to a state ready to deal with the next compression cycle
So I took a look at the factory setting specification for Road / General use and saw 7s, 10s, 11s and a 12. This meant nothing to me because I had no idea of what Min and Max were.
25.
25 is the number of clicks from taught to sloppy in all 3 adjustable settings, so now I had an idea of what a 7 and 12 actually meant: 28% and 48%. Except… that is 28% (7 clicks) from fully taught, so 18 clicks (72%) of firmness from fully sloppy. I won’t lie, at this point I threw away my cold tea and poured a glass of red. Things became a bit clearer.
So now I had 3 challenges on the shock absorber settings:
- Having ‘removed’ the tender spring lockout ring, the springs are going to compress more which means more travel for the shock absorber. I wanted to make the High Speed Compression softer to soak up the bigger hits and do away with any ‘sudden’ changes in dynamics
- A side challenge of removing the tender spring lockout ring is that I need firmer settings for Low Speed Compression to keep everything in check in corners and when accelerating / braking as well as handling the smaller bumps at speed
- Rebound settings. Well I left this for now. Let’s see how changing 1 or 2 parameters fare before getting completely lost in all of this…
I changed the rear by only 1 or 2 clicks (4% / 8%) as they were already doing a good job and there is much less travel from those firmer springs in any event. I softened the front High Speed Compression from 48% firmness to 32% firmness and stiffened the Low Speed Compression from 72% to 80% firmness.
After a brief 1 hour round trip to fetch the paper this morning, I returned home grinning from ear to ear. The Fox suspension is everything I had hoped for. It may not be 100% to my personal liking right now (after day 1), but at least I have options to research and experiment with.
So changing firmness settings stopped the ‘metallic twerking’ at the front?
Well not quite. There is still some ‘clunking’ up front under hard braking and cornering, but I suspect this is the ‘floating seat’ travelling up and down the threaded shock absorber. There is only about 1mm gap between the outside of the shock body and the inside of the floating seat. If the shocks were perpendicular to the ground, I can imagine they’d glide quite nicely. Because of the estimated 45-degree angle of the shock absorbers on the Nomad, I can see how the floating seat on a 40cm spring set will grate over the shock threads under extreme forces. I’m not worried that springs will start working loose from their seat or interfere with steering or braking. It’s just… different. Ideally, I'd probably look for a seat with longer guides top and bottom to reduce lateral movement. Anyway...
Overall – I’m chuffed!
Thanks for reading this far. Please note that I am NOT a suspension expert. I am a complete novice who enjoys trying to figure things out. I am sharing this purely as my personal experience and to – hopefully – offer assistance to others, even if it is a guide in what NOT to do. That said, if you’re reading this and have any advice / experiences, please do let me know! As much as trial and error is fun, I’m also quite lazy and would welcome any advice.
When I put a deposit down on a Nomad 2, I’ll be putting Fox suspension at the top of my list. The cup holder will just have to wait…
Cheers all.
