I was looking for a suspension option for my Fatboy and came to the quick realization that there just aren’t that many choices out there when it comes to 150mm forks that can accommodate 5” tires. You really only have 3 choices; Bluto, Lauf or the Wren Sports fork. Everyone of these forks has worked on finding there niche in the fat bike world. The Bluto is known as the standard for fatties that need mid range travel while the Lauf is known for being lightweight but low travel. Then there is the Wren fork; which is building a following as a high travel, rigid and smooth fork. Being a suspension enthusiast, I quickly gravitated towards the Wren. Not only did I like the qualities I have seen with it, but its just plain cool looking also with the inverted design and carbon fork guards!
So I decided to reach out to Wren via email and got a response from Kevin the owner. Later on I called the contact information from their website (http://www.wrensports.com) and a gentlemen named Russ answered the phone. Little did I know at the time that Russ is the suspension guru for setups and teardowns at Wren. I chatted with Russ for a short time and he said that I would be hearing back from Kevin. Wow, seriously, the owner of the company will be calling me back. This just shows the type of customer service these guys give you!
It wasn’t that long after a conversation with Kevin that I had a beautiful 150mm hub fork with 110mm of travel sitting at my doorstep. Keep in mind that Wren does offer several different hub widths and travel lengths for other frames. Take a look at their website for more detailed information.
Lets start with the way the Wren was packaged. If this fork got damaged in shipping I’m thinking it would have had to been run over by the mail carriers semi. Double thick cardboard box encasing individually wrapped in plastic components with thick layers of bubble wrap around all of that. I don’t know what it is about good packaging that makes me happy, possibly it's the fact that my stuff arrives ready to rock.
So what’s in the box;
15mm Thru Axle
Carbon Fork Guards
Fork Guard Clamps
2 Hose Guides (hose routing)
2 Travel Clips (10mm and 20mm)
Wren Fork Manual
TwinAir System Explanation
So what are the specs of this fork;
Hub Spacing: 150mm
Tire/Wheel Size*: 26" x 5.0", 27.5" x 4.0", 29" x 3.0"
AC Length: 530mm (adjustable to 520mm, 510mm or 500mm)
Travel: 110mm (adjustable to 100mm, 90mm or 80mm)
Steerer: Tapered - 1.125" ~ 1.5"
Crown: AL6066T6 forged
Stanchions: AL7050 hard anodized, 36mm
Uppers: AL7050 hard anodized, 43mm
Axle: QR15 included
Brake: Post mount
First thing is first before the fork even sees my bike, I needed to check out the performance of it. The best way anyone can test the true fork performance is using a tool called a suspension dyno. The Wren was setup on the dyno and many runs were executed to learn about the properties of the fork. We looked at things like base adjustability, seal drag and other properties. These graphs can’t be shown here but I will say this much; I’ve yet to see another fork with the amount of user adjustability right out of the box as this one. It was quite incredible to see what you can do with this thing if you have a bit of knowledge of how the TwinAir system works in conjunction with the compression and rebound adjustment on the other leg. You can go from minimal amount of resistance to absolute lockout (our Dyno wasn’t too pleased with this setting) when adjusting the compression side and from snails pace to full blown cheetah return on the rebound side.
After seeing the performance on the dyno I was incredibly excited to get it on the Fatboy to check it out. Installation was a breeze. I did have to re-lace a new hub into the stock Fatboy wheel, I decided on a Hope, and throw on a headset crown race on and take a bit of the steerer tube off. Just something to remember if you are going to be converting a rigid Fatboy into a trail slaying machine equipped with the Wren. I left the fork with the 110mm travel for the initial installation which puts it at a AC length of 530mm. This can be adjusted using the travel clips that came with the fork.
Wow, what a sight once I got the fork on the bike. The travel felt incredibly smooth with absolutely zero stiction during the entire length of travel. This surprised me a bit as well because the fork really has not been broken in yet. I expect this only to improve with time which is incredible. I really have never felt a fork this smooth, even when comparing to the motocross stuff I’ve been around. The fork just fit. The looks, the scale, the whole package was exactly what I was looking for. I just couldn’t wait to get it out on the trails.
One thing I noticed was the AC length seemed a touch longer than what I original wanted. Huh, that's an easy change according to the instructions on Wrens YouTube site (https://www.youtube.com/watch?v=uvLdCPausWo). I simply needed to open up the left leg and put in a 10mm travel clip. This took all of about 10-15 mins and I never even pulled the fork off the bike. The process was incredibly easy for any at home bicycle mechanic. The only thing that standard bike mechanic may not have is a good 26mm 6 point socket to loosen the retaining nut on the left leg. Other than, standard tools apply. Just remember to bleed all air out of the TwinAir system before loosing the retaining nut!
So what is the effect if you change the travel length of the fork;
110 mm of Travel – 530 mm AC
100 mm of Travel – 520 mm AC
90 mm of Travel – 510 mm AC
80 mm of Travel – 500 mm AC
Now that I got the AC length to something I preferred, its onto the fork setup. I myself typically find I like a bit of a stiffer fork with as much rebound as I can control. I decided to keep the TwinAir system balanced so I pumped both sides to 70 psi with equal amounts of strokes from a shock pump. Then I set the compression to the middle adjustment and the rebound about 2/3 of the adjustment. Just feeling the fork travel out by hand in my shop and a few driveway test runs gave me some confidence that this will be a great starting point.
I had to wait a few days to get a decent riding day here in Michigan but wow was it worth it. We had a perfectly groomed 25F day and I took full advantage. First noticeable impressive was how the bike responded to all the little whoops and holes in the trail. They became unnoticeable to me which allowed a lot more focus to be placed on larger obstacles and turns. I also was concerned that I would notice the additional weight when compared to the carbon rigid fork but it turns out that became unnoticeable as well very quickly. Another noticeable difference was the stiffness. I have ridden a few Blutos myself and this fork is just far more compliant in hard turning. I don’t get that uneasy feeling of the fork legs flexing and then snapping back into place. I heard others complain about this with the Bluto and I really believe that the additional size to the stanchions along with the inverted design eliminates this on the Wren.
The fork was noticed by a lot of people out on the trail. It seemed people really gravitated towards the inverted design and the large stanchions. Every person that took it for a spin brought it back with a huge smile on their face and really liking it.
Overall, my general feeling is that if you are looking for a fork that can accommodate any riding condition you may throw at it rather it be roots, chunky rock, smooth singletrack, snow etc. this is the fork you need. You will not be disappointed with the smoothness and plushness it can provide to any type of riding. The ease of maintenance will be a huge plus for do-it-yourselfers as well and like I said earlier, it just looks cool.
But I know a lot of you will be thinking, what makes the Wren that much better than lets say a Bluto? For me it comes down to quite a few things. First and foremost for me is the inverted design with the huge keyed stanchions (36mm Stanchion that insert into 43mm Sliders ) providing excellent stiffness. Next up is the amount of adjustment you can get with the TwinAir setup and the compression and rebound adjusters. You just cannot get this type of range from a Bluto. Also, the ease of maintenance and ability to change the travel length simply is a huge plus. Lastly, it can accommodate a 5” tire.