Rated: WP Xplor Fork Cap Preload Adjusters

A product the Transmoto team has tried, tested and would recommend to a mate.

WHAT IS IT?

WP Suspension’s Xplor Fork Cap Preload Adjusters are an aftermarket part (available through the KTM PowerParts or Husqvarna Accessories catalogues) that replaces the entire cap on WP’s 48mm forks, and allows you to alter each fork leg’s spring preload settings by up to 6mm by hand. You simply take the weight off the bike’s front wheel and turn the large, wingnut-style adjuster to your desired setting.
These tool-free preload adjusters were first released in conjunction with WP’s 48mm Xplor fork (which arrived on the 2017 KTM and Husqvarna enduro ranges), but it is also possible to retro-fit them to WP’s 48mm open-cartridge fork (which is used on all pre-2017 KTM EXC/EXC-F models).
For the past year, we’ve been using these tool-free adjusters on a few project bikes (as an aftermarket part on the KTMs, and as standard equipment on the Huskys), and here’s what we can tell you about them…

WHY WE RATE IT

PROS…

- Easy to Fit – Replacing the standard fork caps with WP’s Xplor Fork Cap Preload Adjusters is a simple process that takes all of about 10 minutes. You can even do it with the fork legs in the bike, though you’ll have to back the triple clamp pinch bolts off completely. Just note that it’s critical you fit the cap with the red rebound clicker adjuster on the right fork leg. Also, you do need a special tool (a WP fork cap wrench) to remove to Xplor fork’s standard fork caps, meaning you can either hit up a mate or a dealer, or purchase one for $45 from a aftermarket supplier such as Motion Pro.
- Tool-free adjustability – As WP’s Xplor fork runs both its compression and rebound clickers within easy reach on the fork caps (a la WP’s 4CS fork), it encourages you to experiment with the fork’s set-up and get it dialed to suit you and/or the terrain. And the preload adjusters allow you to take that adjustability a step further. A big step further. How so? Well, because changes to fork spring preload affects the entire geometry (and front-to-rear chassis balance) of your bike, they give you a much wider range of tunability. With less preload, the fork sits down into its stroke and helps the bike turn quicker in tight terrain. Or when you’re riding in sand or fast desert-style terrain, added preload will make the fork ride higher in its stroke for more high-speed stability.

‘Two-stage’ tuning – You’re much more inclined to perform a trail- or trackside spring preload adjustment when it doesn’t require tools, especially when you can couple those settings with the Xplor fork’s easy-to-reach clickers. In other words, the preload adjuster is like a ‘coarse’ tuning option, which can then be complemented and fine-tuned by clicker changes. Sure, WP’s previous open-cartridge fork comes with 10mm of preload adjustment. But with it, you need to grab a 24mm spanner from your bumbag or toolbox to make any changes (plus, with its compression clickers inconveniently positioned in the base of the fork legs, you can’t make on-the-fly changes to compression damping).
Versatility – If you’re like us and ride your enduro-model KTM or Husqvarna in a variety of soil types and conditions, out on the trail and/or on a motocross track, the preload adjusters really come in handy because they make your bike much more versatile. And when you share your bike at a pony express-style event with a mate who weighs a lot more or less than you do, the ability to change your bike’s fork spring preload is a godsend. In fact, it’s almost a necessity if both riders want to enjoy their ride/race.

CONS

Range of adjustment – WP’s open-cartridge fork comes with 10mm of external preload adjustment, so by making this new system tool-free, WP has had to sacrifice 4mm of adjustment. Having said that, very few riders dialled more than six turns (or 6mm) of preload into the open-cartridge fork. If they did, it was a sure-fire sign that they needed to fit firmer fork springs.
Adjustment increments – Preload adjustments on WP’s open-cartridge fork are generally made in one-turn (or 1mm) increments, so there’s been some criticism that 3mm increments offered by the tool-free preload adjuster are too large. This is somewhat misguided because the tool-free preload adjuster actually gives you five settings (0mm, +1.5mm, +3mm, +4.5mm and +6mm), which is achieved by ‘offsetting’ the left and right adjusters. For example, to get +1.5mm of preload, you would turn one preload adjuster to +3mm and leave the other at 0mm.
Durability – More moving parts always opens up the possibility of more failures. And a few suspension tuners have reported the odd issue with cracked adjuster components leading to leaks.
OEM fitment – It’d be nice if KTM followed Husqvarna’s lead by fitting these tool-free adjusters to their entire enduro model-range, rather than their Six Day models only.

VERDICT

At $380, these WP Suspension Xplor Fork Cap Preload Adjusters are not cheap. But they’re an ingenious solution and we reckon they’re one of the best mods you can make to your KTM enduro bike for the simple reason that they not only add to the range of adjustment for a critical performance component; they also make it quick and easy to make those changes. In doing so, they encourage you to experiment with your suspension and chassis-balance settings. That helps you understand how your bike responds to changes, and how to optimise its ride for you. If your bike runs the older-style open-cartridge 48mm WP fork, it’s more difficult to justify spending $380 because that fork already comes with 10mm of external preload adjustment (albeit not tool-free). Plus, you’ll need to check on fork cap compatibility, as the Preload Adjusters changed from a left- to right-hand thread in 2018.

PRICE: $380 // www.ktm.com.au

KYE ANDERSON’S TAKE…

Seven-time Transmoto Enduro Event Ironman champ, Kye Anderson, has also been testing WP Suspension’s Xplor Fork Cap Preload Adjusters for the best part of a year. Here’s what one of Australia’s most successful endurance racers had to say about them:
“I for one have solely relied on my fork preload to make adjustments during cross-country races in the past. Once I have found a comfortable suspension set-up at the beginning of the season, I almost wouldn’t touch the clickers throughout the year.

For example, during cross-country styled events like Transmoto’s 6- 8- and 12-Hour enduro races, I never know exactly what the track has to offer until I’m in the thick of it racing solo. So when the track changes and breaks down as much as they tend to in these races, it’s really is difficult to have a perfect suspension set-up. That’s why at numerous stages during each Transmoto race – after dissecting the track in my mind to work out which sections the bike is working well and where it is not – I’d make a pit stop to make adjustments that I think will bridge the gap between the handling of the bike between sections. My mechanic would either take a turn off the fork preload or put another turn on – without touching the clickers – and nine times out of 10, this worked perfectly.

“Since then, with the introduction of the WP Xplor fork on the 2017 models, the standard package from KTM doesn’t allow for external/easily accessible adjustment of the fork springs’ preload. Yes, there are spacer kits available to place under the fork caps. These are fitted in between the inside of the caps and the top of the spring, and apply more preload on the springs. But each time you want to change the preload, you have to remove the handlebars and fork caps to do so. Which is not ideal.

“With the new Xplor Fork Cap Preload Adjusters, however, you don’t need any tools to adjust spring preload. You just take the weight off the front wheel (by placing it on a static stand or leaning it over on its sidestand) and then twist the preload adjuster clockwise on one fork cap at a time to add more preload on the spring in 1.5mm or 3mm increments, or anti-clockwise for less.

“I have tested these tool-free preload adjusters on my 2018 KTM 300EXC TPI at a number of Hard Enduro races in Europe and have found them extremely beneficial in dealing with the wide variety of terrain and types of races we have to cope with at an international level. On the one hand, you’ve got the ErzbergRodeo Hare Scramble prologue, which is an insanely fast and loose dirt road with sharp hairpin turns that make for some very hard braking situations. The ability to apply additional preload on the fork springs really helps keep the front-end from diving and makes the bike stable at high speed. Then on the other side of the spectrum, when I do some really long and gnarly trailriding, or at Transmoto’s Enduro Events, I like to run less preload (like +1.5mm to +3mm) to help the bike turn sharper and because I believe it makes the ride less taxing on the wrist, arms and entire body.

“These preload adjusters are also very effective if you’re mixing up your trailriding with a bit of motocross because using the adjusters to give you up to 6mm more preload stops the forks from soaking up all your speed on the upramp of jumps. In effect, it helps bridge the gap between an enduro bike and motocross bike for the average weekend ride. And if you come from a motocross background and don’t like the feel of ‘enduro-styled’ forks, this is an easy way to make the bike feel like your motocrosser.
“Overall I think the Xplor Fork Cap Preload Adjusters are an essential investment for any rider, ranging from weekend trailriders to serious racers, as you can never have too much adjustment.”