TranzX Dropper Seatpost - Review
TranzX is a house brand for JD Component Company, who have factories in Taiwan and China that produce a modest range of dropper seatposts. The TranzX model YSP12 reviewed here (which can also be found under the "BrandX" name at Chain Reaction Cycles), came into my hands while testing a series of affordable trail bikes this fall. The bike I was reviewing wasn't equipped with a dropper, so off to my local bike shop I went, where I discovered that I could purchase a 125-millimeter-stroke, internally-routed TranzX post for less than $150.
The TranzX dropper appears to be well made, with a highly-polished, hard-anodized black finish and a RockShox Reverb inspired saddle clamp. Side play was almost nonexistent, and the internals are powered by a replaceable cartridge, which can be pressurized via a Schrader valve hidden beneath the saddle clamp to fine tune its return speed. The TranzX post is machined from 7075 aluminum alloy and weighs 545 grams. Its cable-actuated mechanism is both simple to install and adjust, and two types of remote levers are available: a vertical lever that requires minimal space on the handlebar, and the more conventional paddle lever that you'll see in this review.
TranzX Details:
• Construction: High-strength 7075 aluminum, replaceable cartridge
• Cable-actuated with internal routing
• Stroke: 125 (reviewed), 120, 100, 80mm available
• Sizes: 30.9 and 31.6mm
• Air-adjustable return stroke
• No-set-back, 2-bolt saddle clamp
• Weight: 545 grams
• MSRP: $150 USD
The two-bolt clamp head is similar in function and design to the RockShox Reverb, which is a good thing.
Riding the TranzX Dropper
Before you can ride your new dropper, you'll have to install it. Fortunately, this is an easy proposition. Cable-actuation means that you can either work the cable or the housing through the inside of the frame, which ever is easier. The fixed end of the cable slides into the remote paddle, while the free end is fixed to the post's actuation mechanism by a set-screw-barrel. Set the barrel so there is no free play in the post's actuator lever, tighten the set screw, clip the excess cable, and the hard part is over. I discovered that the TranzX paddle remote lever was a better fit inboard of the brake lever perch and that's where I left it.
On trail, the TranzX post operates smoothly, with a slightly damped return and a similar feel when compressing it to the retracted position. That slow retraction took some getting used to. The Fox Transfer post I had been using previously snapped to its fully bottomed position so easily that the small amount of resistance the TranzX gave me seemed excessive for a couple of rides. Originally, I was going to add some air pressure to the return spring to speed up the post, but that would have increased the retraction effort as well, so I found a pressure that felt balanced in both directions and called it good. Now that I'm used to the sensation, however, I rarely give it a thought.
The TranzX remote paddle tucks inboard of the brake lever.
Tiny threads of the adjustment barrel seem vulnerable in a crash.
As mentioned, there was almost no side-play in the post when I installed it, and that's how it remains after giving it a good thrashing. I am impressed so far, and if the TranzX can survive through the winter season, I'll call it a win. Less impressive, however, is the remote lever. which feels cheaply made, both in its tactile feel and in the way it flexes during operation - but in its defense, it has been functionally reliable and has not required any adjustment or attention since initial setup.
Pinkbike's Take:
 | I am happy to report that the TranzX model YSP12 has not given me any trouble, and that alone elevates it to above-average status. I have no clue whether or not a replacement cartridge could be found if a customer needed one, but considering the post's 150-dollar asking price and quality construction, I'd say the TranzX is a low-risk purchase for a cash-strapped rider who needs a good dropper. |
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www.canecreek.com/products/suspension/accessories/dropt
The stock lever while nice isn't so friendly. The shape of the paddle means you will probably place it so it doesn't rub on your brakes which in turn means it wont be where you really want it.
Had to sort the one that comes with the cheaper Jeffsy for a friend, cable actuated, so finicky! (can't remember the brand).
The tension of the cable was a pain to get right and the length was a pain to adjust. Not to mention that the action isn't as smooth and the feel of the lever pulling the cable is well cheap...since it's half plastic.
www.chainreactioncycles.com/ca/en/brand-x-ascend-ii-dropper-seatpost/rp-prod159176
Modern 2-bolt zero offset seatposts were invented almost simultaneously in Canada and the USA. Interloc Racing Design stateside and Syncros in Canada. IRD filed for and were granted an essentially worthless US patent for them (worthless because it was pointed out in a magazine at the time that these were just re-invented and there were 2 bolt seatposts of this type a century ago). Syncros was smart enough not to waste filing for a patent for an existing invention, they improved on the design anyway.
THEY were also the ones who first started using a brass socket washer for the bolts, to eliminate creaking... NOT Thomson. Thomson posts copied every feature from the Syncros posts except the hole in the bottom to pass a lock thru, and the usage of a head pressed and bonded into the post shaft (Thomson went with a 1-piece machined head and shaft design). I have actually broken the head of a syncros post free and snapped the top of the shaft in the process.
Years ago, I knew a guy who, as an exercise in proving how screwed up the patent office was, by creative wording, and filing the applications with all the FEES paid up front, was granted valid US patents for essentially what were "the wheel" and "fire". That's ultimately as far as the USPTO vets an application anymore and as far as they have for 20 years. Are the fees paid in full ? If the answer is yes, then grant the application even if its for a pre-existing invention they could have proven already existed JUST by searching their own database of existing patents.
That's how Specialized for example, got patents on inertia valve shocks, which they didn't actually invent the idea of, and by not disclosing their KNOWING there was prior patented art in existence. They KNEW the shock technology already existed, because they had licensed it, from its actual inventor, a fellow named Don Richardson. who unfortunately didn't specifically mention bicycles on his own patent application, among the other vehicles he did mention it being applicable towards. Perhaps other old people will remember that name, especially any in the motorcycle world.
Why ? Well this little japanese company tried stealing a previous invention from him... and he took that company to court and WON. The company ? Suzuki.
law.justia.com/cases/federal/appellate-courts/F2/868/1226/17438
@deeeight @Socket
If X-Fusion doesnt release the 150 Manic (and back the promise of a cheap cartridge) will probably pull the trigger on the 150 BrandX/TranzX.
Out of curiosity on bike-discount they have a 170mm in description but not available for selection.
Kona is putting these on their Process SE bikes now.
Same remote as Shimano...may speak to where Shimano has theirs made?
Look closely and you will see many of the same parts used in PNW also, but I believe the newest PNW posts have better internals....or so is my understanding.
WRT the PNW post having upgraded internals, how? the internal is one sealed gas strut... I don't think that can be upgraded because it either works or it doesn't. There are different Brand X/TransX/Raceface/PNW posts that are all the same OEM post but use 6061 vs 7075 alloys. The anodizing lasted much longer on the 7075 version but if you look up the reviews from all of these posts it seems most reviews give transX/Bx posts positive feedback but negative for the pnw/raceface posts that use this OEM.
Said no one
The one thing we all need to be aware of is all dropper posts will eventually fail. So why spend more than necessary. So far this post has been great. Works well and reliable. So why spend $300-400 for a dropper post that will eventually fail? I’ve been on mine for seven months now and it works exactly as did from day one.
Got me thinking though, how many frames with 27.2 seat tubes are internally routed.....?
www.mediafire.com/convkey/0e5e/98edfe48ehcscuwzg.jpg?size_id=7
www.mediafire.com/convkey/e471/qmh420l5jyx0w26zg.jpg?size_id=7
www.mediafire.com/convkey/6884/25169r72cod3begzg.jpg?size_id=7
Good product, but must to be open and grease before use...it's dry inside !
In this case, the bike came with a Charger 2.1 Pike...good! Super Deluxe shock with no lock-out... I can live with this as the bike has a fairly pregressive rear end. Outstanding wheel set (for the price). Full GX 52 tooth drive train and repsectable Sram G2 brakes... this last bit I was surprised with as I've heard bad things about the Guides and I've always been a Shimano man. Good things to say about the new G2s and the GX.
But I'm talking the dropper post.
Simple in appearance.
Likely a part that is solely specked on bikes from the manufacturer.
No way (that I can see) to add or subtract air.
And there's that mystery remote.
However, I could live with all of this (for a time) were it not for the fact that the post (periodically) locked up on me in the raised position.
I've taken a look at the actuator and had ruled in that it gives when I take a pair of pliars to it. Something is seizing. Either the cable within the housing... or the pin that slides into the bottom of the post... pressed up by a little swing arm of the actuator. Possible that the linkage of the actuator itself is seizing. Everything is greased nicely. I'll be replacing the cable and housing first.
It feels stout, has a nice clamp, and works well (so far). However, two complaints:
Lever action - mine is different than pictured, and it takes a real shove. I'll look into something better (gutted SRAM front derailleur shifter, or Wolftooth)
Zero-offset - at least mine is. It also has a really long clamp, so I found it hard to jam the seat all the way back. I went to a different seat with a long front rail, which helped. But it's weird, most mountain bikes / bikers used 20-25mm offset seatposts.
I'd like to see a long-term review to see how it holds out?
However, the Brand-X DOES NOT have a Schrader valve under the seat clamp. Just an M8 nyloc nut. I would assume that the internals are therefore equivalent to the under-praised Giant Contact post i.e. just a gas cartridge similar to what is in your average office chair.
The Trans-X had an air valve on it (I had to up the pressure to make the post return as out of the box it was something like 110psi in it). If you have a Schrader valve it is under the saddle clamp so you need to take off the parts. The cap is a rubber grommet which you can pry out with your fingernails or the hook end of a small allen key. If you take off the saddle clamp and all you see is a nut, then you have the same as me on my Brand-X post.
Funny thing was, even the instruction pamphlet said that the post would need pumping up to circa 220psi.
Thanks!