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Dammit reading that review of the Intend doesn't help curb the want for one.
Would love to buy the stripped down Essential and drop iny Ohlins 36 air cart and TTX18 damper. Best of both worlds.
Get it. The air spring is fine and so is the damper. I have no desire to replace either and I am coming off a $$$ Avalanche damper in a new 2023 36 chassis. I may tinker with the damper for the sake of adding moar shimz eventually, but the Essential just rides great in the factory configuration out of the box. And on top, you get some plush German TP as a bonus!
The PUSH Industries Nine.One
Specifications
150mm-170mm travel (10mm steps), 36mm stanchions, bushing overlap 145mm, coil sprung, 15mm floating axle, pneumatic bottom out control, weight 2960g,
Chassis
The 9.1 crown is large with massive overlap on the 44.5mm aluminum upper legs which are bonded in. Specialized developed a fully bonded alloy crown/stanchion system for the E160 fork around 2010 while I was a member of the engineering group. It is a great alternative to the traditional press fit assembly method for a fork CSU, and in some ways superior.
The moto inspiration for the 9.1 design is apparent, the fork lugs and axle are mini versions of what is found on a motocross bike. The drive side of the axle floats in the lug allowing for hub width discrepancies. The lugs are quite wide and each side uses qty2 M5 fasteners for pinch bolts.
One of the clever features of this fork is the “speed bleed” system. There are bleed ports in the upper legs positioned just above the lower bushings. They allow for injection of bath oil (with a syringe) after the fork has been assembled, as well as to replace the bath oil without dropping the legs. You can also inspect the oil to see how dirty it is and if the fork needs a full rebuild.
9.1 bushing overlap is 145mm which is 15mm less than the Intend Edge, 30mm less than the Fox Podium, and 20mm more than a non-inverted RS Lyrik (MY21 version).
Regarding bushings, I checked the bushing fit and chassis alignment on the 9.1 after roughly 4 hours of ride time and found the fit to be tight.
PUSH became aware of this video and got in contact as they wanted to get the fork back for inspection. The fork was sent back and they ended up changing both stanchions with the resulting bushing fit being much improved.
Spring
The 9.1 has a steel coil spring, with available rates from 30lb/in to 60 lb/in in 5lb/in steps (45 and 50in/lbs tested). Travel is adjustable between 150, 160, or 170mm by removing the spring plunger assembly and changing the internal length. The spring system is very quiet and does not have the top out clunk that is common with coil systems like the Vorsprung Smashpot or PUSH’s own ACS3. There is a pneumatic bottom out system that is adjustable between 5-50psi and acts in the final 20mm or so of travel.
Damper
The damper is a sealed unit with a spring backed IFP and is installed right side up in the fork with the damper rod attached to the bottom of the leg. It has adjustable high speed compression, low speed compression, and low speed rebound. There is not much information available regarding the details of the compression damping assembly, and I have not yet pulled it fully apart. The structure itself is similar to the PUSH HC97 which is a poppet valve design.
I have run the PUSH HC97 compression assembly for the Charger 2.1 damper, and found it to have a platform feeling that is typical of preloaded valve designs. No matter what I tried, the HC97 was on the harsh side in terms of compression damping. The 9.1 damper can be quite firm if closed off, but it seems to have a much larger tuning window and did not have the same harshness as felt with the HC97. It feels like it flows more oil and is less prone to choking at higher shaft speeds.
Rebound damping is a standard piston and shim stack. The rebound piston (mid valve) is impressive with large ports and a good amount of float for the check valve shim.
The factory HSR damping was a bit stiff for me, and I did soften the rebound stack from the stock tune. Bleeding the damper is simple if you have the PUSH bleed fitting (which is also used to inject bath oil into the fork).
Certification/Testing
Unknown apart from internal testing by PUSH.
Ride Dynamics
Initially the 9.1 felt more like an air fork, it did not have the supple feeling coil spring forks are known for. This improved after the stanchions were replaced. However, when I got the fork back from PUSH, it had a very minimal volume of bath lube which I was told is the current factory spec (the prior spec being 30ml per leg). The bath lube oil was also changed from Motorex 10wt to Motorex Supergliss which is what I typically run. After increasing the volume to 20ml of Supergliss per leg, the fork finally began to have the buttery coil spring feel.
Compared to the Intend Edge, the PUSH 9.1 has a more direct feel. There is increased feedback through the grips, and it seems to get hung up and deflect more. The chassis is quite a bit heavier than the Edge and likely stiffer. The 9.1 is by no means harsh or overly stiff, it just has a more connected feel with more feedback, where the Intend Edge is very muted and simply erases trail chatter. Being an inverted design, the 9.1 excels in rough conditions.
The 9.1 damper has a substantial tuning range. With the clickers open it is very free, but can develop a lot of compression damping if closed off.
Thoughts/Issues/Misc
Although ridden hard in a variety of terrain, there are not yet 20 hours of ride time on this fork and it is still relatively new.
In addition to the issues with initial bushing fit, the fork also weeps oil from the crown/upper leg interface on each side.
This only happens when riding, and occurs on every ride. Prior to sending it back for inspection, I sent pics of this weeping to PUSH and the response is below:
As for the seepage, that's not oil. It's moisture that forms between the crown and the upper tube where there are purposeful voids in the adhesive area. We've seen it with a handful of riders who pressure wash their bike, ride in wet conditions, or live in very humid areas.
When mixed with dust, it forms a sludge that appears like oil. Our engineers have recreated it in our test lab successfully, and it is of no concern.
This is confusing as I live at 7200’ where humidity is rarely above 40%, have never sprayed the fork down with water, nor has it been ridden in wet conditions. The seepage looks like bath oil, feels like bath oil, and smells like bath oil. I’m keeping a close eye on the crown/leg bond area, and hopefully the seeping will simply stop at some point. 🤔
Awesome work. 10/10
That seepage does not look good no mater what it is.
Funny how it always seems to be an user issue/different vendor issue with Push if there is something unsual with their product. I get some Steve Jobs "you are holding it wrong" vibes from that...
Thank you for these detailed reviews.
You might have sold me on an intend Hero or Edge to match the 140mm (current)-150mm(if I pull a travel spacer out of the rear shock) rear travel on my trail bike.
The statement from Push
"As for the seepage, that's not oil. It's moisture that forms between the crown and the upper tube where there are purposeful voids in the adhesive area. We've seen it with a handful of riders who pressure wash their bike, ride in wet conditions, or live in very humid areas.
When mixed with dust, it forms a sludge that appears like oil. Our engineers have recreated it in our test lab successfully, and it is of no concern."
This leads to an obvious question!
Why are there voids in the adhesive area that are open to the elements?
This seems to beg for long term corrosion as dust, dirt, and moisture get in those voids and abrade the anodizing on the aluminum parts as they flex.
My thoughts exactly, voids and porosity are typically the enemy of a bonded structure.
A uniform and consistent adhesive layer is the goal.
The "weeping" from the windows of the crown is not very common, and mostly traced to customers who pressure wash their bikes. They stopped pressure washing, and we stopped seeing a problem. As for this specific fork, it could be residue from assembly, or it could be other factors. In each case, it's a temporary factor that, if cleaned, goes away.
This is something we didn't experience in testing over the years, but it is something that we have seen in a handful of customer forks. We were able to recreate it here in our test lab via several experiments, and have an understanding of what is causing it.
As for the voids, I'm not able to go into much detail here without disclosing information regarding how the upper structure is assembled. As the only company that doesn't press-fit the crown assembly together (and a small company at that), we must protect our technology. We're also not talking about a very large area here, but rather a very small section near the window of the crown that has a clearance of approximately 0.001"-0.003". It's amazing how even a small amount of moisture mixed with a little dust/dirt can make such a mess. Even though this has only affected a small fraction of forks shipped, we are looking at ways of improving it, as cosmetically it's not awesome.
Darren
Thanks for the answer.
I have not watched many of the numerous Fox Podium reviews as I try to avoid the influencer type content, but came across this from JKW and it reminded me of something I noticed when first swapping from a traditional to inverted fork; the front brake seemed to work better.
Same brake, same wheel, same tire, same trails; it simply felt like there was more control and braking traction available with the inverted fork.
With the overbuilt crown and large upper legs required to get the desired level of torsional stiffness comes an increased fore/aft stiffness which can be felt when using the front brake. The fork chassis has less tendency to flex and load/unload under braking, which results in an improved function and feel.
https://www.youtube.com/clip/Ugkx937dcDMr1vzN0CjEfTX_Sp3BoEuJvmc0
PUSH is kidding you, this is not a normal thing and demand a replacement of the defective part.
Awesome name 🤣. Perhaps SWS could apply trial by fire - if the fork tears burn, they aren't water (or stigmata).
I love the slow mo side-by-side comparison JKW did in that video, and I agree that on the Podium I'm testing the front brake feels instantly better than on the RSU fork it replaced. I find that I can use the front brake in more places without sliding and without harshness, and the ability to use my front brake more is a change that my rear brake pads are celebrating.
What a great read, thanks SWS. I have a 25 Intend Flash and damping sounds very similar to your Edge feedback, I’m a fan.
New game - one hub, two caps-s. Hadley XC front hub with standard 15mm endcaps vs properly executed torque caps. Will I be able to tell a difference in torque stiffness of my Intend fork?
can you thread those together like thread together bbs?
Yep, the two halves thread together to form a decently stiff "outer axle".
Mostly irrelevant, but interesting: I saw someone with a 2015 Rockshox RS1 this weekend, and just for funsies I asked if I could try twisting it "for science." Holy cow, it's so flexy when you do the wheel between the knees/handlebar twist test.
I rode an RS1 for a while. Was so flexy I downsized my front rotor because braking hard pulled the wheel to the left.
Looked cool though
Paper products from Germany can only mean one thing, new fork day!
This is the Intend Flash 35, it can be run from 160mm to 190mm.
Very similar to the Edge; but with a more robust crown, longer legs, and slightly different uppers.
After initial riding and then a full tear down and inspection, there will be some parallel testing with a 35mm Boxxer. Both forks will be run at 190mm of travel on a DH bike.
The capability of the 170mm inverted forks at Angel Fire was so impressive that a direct comparison of a longer travel version to a full dual crown DH fork should be interesting. There will be timed runs as well to verify perception vs reality in terms of performance.
welcome to the club
does it feel torsional stiffer than the edge when you try twisting it?
I'm waiting for them to release the Flash 38 for my Turbo Levo
I can understand, the "new" Flash with 38mm stanchions, 20mm axle, 2x pinch bolts per side (I believe?) looks pretty interesting.
Whats the current tax / tariff to get these in the US if not a secret?
No tax/tariff charges on this side, $140 in shipping/paypal/parcel fees from Intend and took 8 days to get from Germany to Colorado.
But you never know these days......
Another follow up. I have now had this fork on a few rides. I texted cornelius once again about the small bump sensitivity and i got a very quick reply again. This fork was laying around for quite a while and he advised me tho loosen up the screw on the top of the air side and move the stanchions. Apparently there was fairly much air traped and it neede to go. Ever since i did this, the fork has been flawless and got a very nice small bump performance.
Im very veryhappy with the purchase, lets just hope it will equally be set & forget as the coil fork it replaced. I dont have time to tinker around too much on my bikes.
Good timing. I just bought a Flash from Intend. The tariff info is helpful also.
As I've noted on this board several times, I have a lot of hand problems due to compressed nerves and damage in my elbows/hands. I took about a year off the bike and decided to try riding again, my bike came with a 36 Factory GRIP2 and it's absolutely beating me to death, no matter what I do with it. Previously the forks that mitigated my problems the best were the Mezzer (both stock and RRT forms), Ohlins RXF36 m.2 coil, and surprisingly the 38 Factory GRIPX2. I had hoped the 36 GRIP2 would work better for me this time, but something something definition of insanity and it's lighting my hands up no matter how I adjust it.
The challenge with me is my weight, I'm 220lbs, so balancing out a fork that is stiff enough, supportive, and compliant enough is really difficult. It doesn't help that the areas I ride are pretty rooty and eroded, which is the worst possible terrain for my issues.
Nothing I do on the bike is truly a 100% fix for my deeply rooted issues, but anything that mitigates it and reduces the number of times I have to stop to let my hands chill out is a win. I'll report in when I get a few rides on it.
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