BikeYoke REVIVE – dropper post with bleed button

What if there was a dropper post, that actually solves and not just improves reliability issues, saves cost and time, and let´s you not need to worry about service time anymore. Bike Yoke promises this package for their new REVIVE dropper. Find all information in the official press release below:

BikeYoke presents its new REVIVE dropper post, featuring one of the most brilliant design features in drop post design in many years. It will start with 125mm and 160mm of infinitely adjustable travel and in 30.9 and 31.6 diameters with a 34.9 version being in planned.

Status Quo

To understand the benefits over other posts, you have to know about the problems of many current designs first:

Many of the popular current seatpost designs are based on a hydraulic lockout-system, that relies on a perfectly sealing IFP (Internal Floating Piston), separating oil from air to prevent the seatpost from getting suspension feeling. There are a lot of difficulties to overcome when using an IFP, because an IFP has to be 100% sealed. If air can go to the oil side, your post will start becoming springy. This happens to a lot of posts in the market already and is the main issue why posts need to be serviced.

Just to mention a few of the issues an IFP design comes with:

High costs

An IFP design requires perfect surface finish of ID AND OD, of both, inner and outer tubes, of the hydraulic circuit. There is a high defective rate during production, and also it is very difficult to keep the quality stable. This means, those tubes are very expensive to produce.

Stick-Slip-Effect

An IFP is a dynamic seal with high preload/squeeze. This causes stick-slick effect on many posts, which you can feel, when your seatpost gets stuck and you need to break it loose manually, because only pushing the remote won´t make it start moving.

Wear

IFPs are usually kept as short as possible to safe build height. But this means, they can tilt inside the tube more easily and cause overly extensive wear and/or leakage. Long tubes and long travel will make it worse, because the IFP has to follow not a straight line inside the tube, but a bent curve, since longer seatposts will obviously have more flex.

REVIVE design

That´s why BikeYokes “REVIVE” features a NON-IFP design, because we think it is too difficult – if not impossible – to make a really reliable design using an IFP. REVIVE only requires 2 dynamic seals in the hydraulic circuit (RS Reverb and KS LEV and Fox transfer use 4 dynamic seals), with those two seals being the ones, that are known to cause the least problems in sealing application: The inner shaft sealing and the piston sealing for the lockout mechanism. The highly critical IFP has been removed, and with it the need of perfect concentricity and finish of the sealing surfaces of the tubes. The lack of an IFP also results in super smooth movement and breaking loose due to less friction.

REVIVE VALVE – Reset your post

The most important and groundbreaking feature of Revive is its “REVIVE-VALVE”.
Even REVIVE can get air somewhere where it does not belong. This can happen for example, when you actuate your seatpost for a few times, while its upside down. And here is where the RESET BUTTON comes into play: Press the “RESET-BUTTON and drop the seatpost by hand. This will automatically reset your hydraulic circuit to “new”. Whenever. Wherever. This is done just within a few seconds and only by the push of a button without even having to remove your drop post from your bike.

One piece lower

Next to creating a completetly resettable hydraulic system, REVIVE also features a one piece lower tube, whereas many posts have the upper bushing (which experiences the biggest load) installed on a separate top cap, which is then threaded on top of the lower tube. Installing the upper bushing directly into the lower tube does not only increase structural strength of the lower assembly, but also provides better load displacement, since the upper bushing can be designed longer without increasing the overall build height. Perfect concentricity with the lower tube and it´s keyways, that houses the 6 pins to eliminate rotational play, is also an attribute that come in hand with a one piece lower tube. Due to the extra wall thickness at the collar area, Revive is also less prone to be affected by too high seat-clamp squeeze.

Serviceability

So, now one might already understand that:

• No air will want go inside the post´s hydraulic circuit, since it is charged with pressure.
• No oil will not go out (or at least very very little oil over the curse of a long time), because of very stable sealing – external sealing has never been a real problem of current post design
• The hydraulic system can be reset to “new” via the unique “REVIVE-valving”

Bushings and keyway pins will wear over time. Usually, the pins wear first and you would want to replace them to reset your rotational play. Exchanging the pins and the lower bushing is simple and does not require any opening of the hydraulic system and can be done within less than 5 minutes.

Here is how you do:

1. Remove the post from your bike
2. Remove the bottom endcap of your post
3. Pull out the upper unit ( including the “stanchion”). The pins will contact the upper bushing and they will slide out of the stanchion´s keyways together with the lower bushing
4. Slide the stanchion back down into the lower tube.
5. Insert the new pins into the keyways and install lower bushing
6. Reinstall the bottom endcap

If you want to do a full service including replacement of dust wiper and upper bushing, then the procedure is the same, except for that you pull out the upper unit completely instead of just stopping after the pins fall out. Then you can remove the dust wiper and upper bushing and clean and lubricate the lower tube, before reassembly.

Specs, sizing, pricing, availability

Travel:
125mm Hub / 369mm length (30.9 and 31.6 diameter)
160mm Hub / 439mm length (30.9 and 31.6 diameter)

Remote:
1-by remote “Triggy”
2-by/3-by remote regular up/down push-button

Weight:
470g (125mm travel/30.9 diameter)(w/o remote) + 25g (Trigger style remote)

BikeYoke REVIVE will be available in January/February 2017.

PRE-ORDER-DEAL

BikeYoke will offer a pre-order deal on REVIVES which will start right after Eurobike for 31 days.
All pre-order customers will get some special goodies:

Price:
349€ (125mm including Triggy remote) (including 19% German VAT)
369€ (160mm including Triggy remote) (including 19% German VAT)

• Free shipping worldwide
• Titanium saddle clamp bolts (original: stainless steel)
• Free I-Spec B or I-Spec II adapter for Triggy remote or BikeYoke Shifty (choose 1 out of 3)

What makes Revive different:

REVIVE Valve

• “bleedless bleeding” – bleed the installed seatpost within seconds only by the push of a button
• REVIVE Valve is air valve and bleed-valve at the same time
• no more internal service needed, when the drop-post starts sagging
• even a full service does not require any external bleeding procedure

No IFP

• IFP requires extremely precise concentric tubes AND perfect “stanchion” inside surface AND perfect outside surface of inner tube – > very expensive and high defective rate during production
• IFP increases friction and noticeable stick slip effect
• IFP requires build length and make the post longer
• Uncritical oil fill: Revive works perfectly with up to +/- 10% oil fill status
• No more air ingestion from air to oil possible

One piece collar + outer tube

• Increased strength of lower tube
• Saves build space (no connecting threads needed) –> extra long critical upper bushing possible for increased load displacement.
• Perfect concentricity for upper and lower bushings -> low friction
• Integrated collar allows high wall thickness for increased seatclamp squeeze resistance at bushing area
• Easy assembly and disassembly

Adjustable side play

• only need to unscrew the bottom foot and sideplay can be adjusted via pins without disassembly of the whole post.

More information can be found on the BikeYoke website.

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Words & Photos: BikeYoke