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Turnagain Cures Cold Weather Blues with new ETR Seal Kit for RockShox Bluto Fat Bike Forks

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Turnagain_ETR_Seal_Bluto_Release_P1

Having just finished our review on the RockShox Bluto suspension fork, Tim and I both agree that the fork is a good thing for fat bikes. Not so good though? The potential for issues when ridden below freezing. Officially, RockShox tells us that the fork will perform optimally from 0° C (32° F) to 38° C (100° F). Between 32° and 10° F, the fork’s performance will begin to degrade, and using the fork under 10° F is not recommended. Considering most of us tend to ride our fat bikes during the winter, this could be seen as a bit of an issue.

Coincidentally, just days after posting our review Turnagain Components has stepped up with an answer. After months of both lab and real world testing, Turnagain is revealing their new Extended Temperature Range (ETR) seal kit which seems to be the answer to our Bluto prayers. More than just a cold weather kit, the ETR seals are designed to work in a wider range of temperatures than the originals. That means even after the upgrade the fork should work just as well during the hottest summer months as the coldest in winter.

Available as standard equipment on their sister brand Borealis bikes, or as an aftermarket upgrade, Turnagain has Bluto’s back…

turnagain seals

According to Adam Miller of Borealis Bikes and Turnagain Components, the Bluto fork uses the same seals found in many other forks like the Reba 29. These seals apparently have a wide enough tolerance that some forks will work fine below their recommended temperature ranges, yet others will fail when air escapes the positive chamber into the negative chamber causing the fork to suck down and collapse.

Because of this, the Turnagain ETR kit consists of 3 o-rings for the air chamber of the fork that are made of a different material which is not affected by changes in temperature. Along with tighter tolerances and Slickoleum grease, the seals have proven to be effective well below zero as well as during the Colorado summer.

Interestingly, Adam tells us that the installation of the kit does not include changing to a different weight oil. They found that opening the rebound 2 clicks was more effective than changing the oil. Not to mention that keeping the stock oil allows the fork to function just as well during the Summer. Turnagain is currently working on an install video which should be available in about a week.

Turnagain rockshox bluto fat bike fork suspension cold weather seal kit ETR  (2)
Tyson Flaharty’s dog Pre (as in Steve Prefontaine) routinely tags along on fat bike expeditions, even in the bitter cold.

Testing extensively with a group of 12 riders out of Goldstream Sports in Fairbanks, Alaska, the team used multiple forks, seals, and oils to carry out blind testing of the ETR kit. In all of their testing, not a single rider was able to get an ETR equipped fork to fail even at temperatures around -20°F. The real world testing was carried out in conjunction with laboratory testing to ensure that different oils, greases, and dirt wouldn’t cause the seals to fail. While many seem to be considering the Bluto as the fork for the Summer months, the ETR kit makes it a favorite for riders like Goldstream Sports Manager Tyson Flaharty, who said, “It’s amazing how much more control and speed I have on my fat bike when I am riding through tussoks and other frozen obstacles in the trail.”

When Adam mentioned the price of the aftermarket kit at $55, you could tell he wished it could be lower. In fact, he even went as far as saying, ” This isn’t a product we’re going to make money on. Due to the amount of testing it took to verify their function, it’s something we are going to sell because it will help expand the world of fat bikes.” Indeed, $55 may sound a bit steep, but until there is a cheaper option it seems like it will be worth every penny to anyone who wants to ride a Bluto year ’round.

Turnagain rockshox bluto fat bike fork suspension cold weather seal kit ETR  (1)_1 Turnagain rockshox bluto fat bike fork suspension cold weather seal kit ETR  (1)

Starting immediately, ETR seal kits are available as a dealer ordered upgrade for any Bluto equipped Borealis fat bike. Aftermarket kits will be available as soon as the packaging is finished, or by the end of the year at the latest.

turnagaincomponents.com

 

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Sevo
Sevo
9 years ago

Love it!

ryan
9 years ago

great idea!

Brian
Brian
9 years ago

So pebax or hytrel elastomer then?

SB
SB
9 years ago

I’ve ridden RS forks at seriously low temperatures (-30º C), and the dampers start to suck long before the air spring threatens to burp. This was with previously-standard-issue 5 wt oil. Maybe the new “3 wt” stuff works a little better. Likewise, getting -30º stanchions to slide through any kind of wiper is a tall order – especially when your lubricating oil has turned almost solid (throw a bit of Float Fluid or similar in the freezer, and check the consistency in twenty minutes…it’s not very slippery).

I don’t really understand how all this was overlooked in favour of a possible air-spring burp. Seems like missing the forest for a single tree.

Fatrider
Fatrider
9 years ago

Does it void the warranty?

rick
rick
9 years ago

ok, so you get the piston head to seal but what about condensation/water building up internally- no big deal .. ?!? ..

brandon
brandon
9 years ago

Why not just lockout your fork when the temp dips below -10? At that point suspension performance is the least of your worries and if you can make it to your destination without destroying your blutos internals with a simple flick of the lock out switch then all is good! mission accomplished 🙂

Simon
Simon
9 years ago

Arlo Englund!!! He made the best upgrades for Judy and Manitou in the mid 90’s. Great to see he’s still around.

Ewain
Ewain
9 years ago

Seems to me that an seal upgrade that makes your fork work where it normally wouldn’t is d*mn cheap for only $55.

Especially if the main reason a lot of people get fat bikes is because of heavy winters, which also happens to be the main reason the forks don’t actually work…

Come on Fox, where’s your fat fork?! 😀

Denny
Denny
9 years ago

Do the turn Again make convertion to straight steerer, too, then?? That is the next project right! 😀

Denny
Denny
9 years ago

wait what! 55 dollars for seal kit!!And a product you dont make money on? ok pinnochio haha

JBikes
JBikes
9 years ago

Seems like Rockshox hired some NASA Challenger shuttle engineers…

liljoe
liljoe
9 years ago

@JBikes, you are on fire today!!

King County
King County
9 years ago

I like that last photo of the fork in action, with the rider up ahead.

cole
cole
9 years ago

Now maybe all the bluto needs is an oil heater so there’s at least some chance of maintaining a functional viscosity.

greg
greg
9 years ago

the guys in this small company sweated the details SRAM should have. good for them, bad for SRAM.
hey SRAM, how many marketing guys does it take to change a light bulb?

Mark
Mark
9 years ago

Ok this is all completely bogus. The fork will have some initial decrease in performance on a cold ride but it is still a friction mechanism. After a short time of constantly cycling the fork temperature will rapidly rise due to friction in both the seals, bushings, and oil, which converts the stored/induced energy to heat. Even if it’s just minimal trail chatter after about half a mle the fork will be many tens of degrees above the ambient temperature. This is a known phenomenon in World Cup racing. Any suspension tuner or company will tell you as much, and many race teams have research that obviously states this. Just ride a fork in any weather and then take temperature reading with a laser thermometer. Suspensions company’s wish his didn’t happen, lol.

Andre
Andre
9 years ago

This is a good idea, next they should make a seal kit for the damper, i have had two rock shox mission control dampers fail from being ridden in the cold. @ Mark, what you’re saying has merit, however in cold teperatures a fork will not warm up quickly and it is prior to warm up that the seals are damaged, I have ruined many forks and hydraulic disc brakes from riding in -15 to -30 C and it is even worse if your bike is stored in a cold garage as all the seals and oils are already frozen. It seems to me that you don’t ride in teperatures below -15 or you would have experienced such issues with your suspension. The best luck I have had with suspension forks in sub zero teperatures are open bath coil dampers, they don’t rely on seals to function, the oil is easily changed for different teperatures, and they are bombproof, I rode a Marzocchi 55 for three winter seasons with zero problems. Sure coil is a bit heavier, but with a ti spring a coil for can be made reasonably light, this is the way to go for fat bike forks, don’t know why they haven’t offered a coil version yet…

Ace Brown
Ace Brown
9 years ago

This should be a warrantee issue from Rockshox. They built a fork for bikes that they knew would be used below freezing. Now we learn that the fork could readily fail if ridden below freezing. Now I’m expected to pay for their error. No way.

Manny O
Manny O
9 years ago

I totally agree with Ace! Rockshox should be reaching out to customers such as car makers are doing when a component fails to their cars, guess what they do? Recall!!! They failed to consider this common usage of fat bikes during the winter season, so they need to make this remedee free for all bluto owners!!!

Jeffrey Hoops
Jeffrey Hoops
6 years ago

Brakes that don’t work in the heat and fat bike forks that don’t work in the cold, oh boy, what a company!

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