D.2 ST-Ro – Dropper Parallelogram Seatpost

Product description – D.2 ST-Ro

The D.2 ST-Ro is both a mechanically controlled variable seat post for continuously varying the seat height and high safety at stops, as well as sensitive suspension post with 30 mm travel. Ambitious (E) city and trekking bikers experience with this first-class manufactured parallelogram seatpost on gravel or cobblestones in the urban environment highest ride comfort! This spring comfort can be optimized by means of the steel spring available in 4 spring stiffnesses exactly to the rider’s weight. This is how the D.2 ST-Ro works for riders weighing 45 to 130 kg. Via the ergonomic handlebar control lever, the rider playfully lowers this vario/spring support by 80 mm before descending, then benefits from a secure stand, e.g. when stopping at traffic lights, from the lower body center of gravity and best riding control. The external cable guide facilitates maintenance work.

Please note the installation requirements!

Technical data

D.2 ST-Ri:

• Material : Aluminum AL-6061-T6, AL-6066-T6
• Color : Black anodized
• Cable guide : external (Ro)
• Spring element : Length approx. 72mm
• Spring travel : Approx. 30mm
• Body height : Approx. 135mm
• Offset : Approx. 17mm
• Rider weight :
  Ø 30,9 / Ø 31,6 : 115 kg
  Ø 33,9 / Ø 34,9 : 130 kg
• Adjustment Range (Travel) : T80 = Approx. 80 mm
• Bearing / linear guide : IGUS polymer high performance plain bearing/ linear guide
• Diameter : Ø 30,9 | 31,6 | 33,9 | 34,9 mm
• Weight : Weight : approx. 940 g (for Ø 30.9; T80 incl. medium spring)
• Saddle clamp with fine adjustment and robust detent
• For saddle rails with Ø 7mm, optionally available for Ø 8 mm
• Scope of delivery : D.2 ST-Ri seatpost incl. neoprene protective cover and instruction manual incl. cable guide, cable and control lever for mounting on handlebars

D.2 ST-Ro remote lever:

• Material : aluminum AL-6061, black anodized;
  Stainless steel, clamp band, black, screws;
  Plastic components
• Clamp diameter : approx. 22.2 mm
• cable guide radius : approx. 7.5 mm
• Weight : approx. 55 g

The D.2 ST-Ro seatposts are supplied with remote levers matched to the model.
You can recognize the correct design by the laser print or lever radius on the underside.

Cable guide:
• Cable sheath: Jagwire approx. Ø 4.2 mm outside, L = approx.1700 mm.
• Shift cable / inner cable: Jagwire approx. Ø 1.2 mm, L = approx. 1800 mm

Gas spring:
• Maintenance-free by,schulz gas pressure spring

• Spring elements in 4 degrees of hardness for adaptation to rider
to the rider’s weight, easily exchangeable
• Saddle clamp with fine adjustment and robust detent
• For saddle rails with Ø 7 mm, optionally available for Ø 8 mm

Installation requirement

NOTE: Carefully plan the installation and the fixing points of the cable guide. You may be able to use existing attachment points and extend them with additional brackets from the accessories trade, or attach the outer casing along already laid cable guides using cable ties.
Make sure that the inner cable and the outer shell are long enough for the planned installation route on the frame!
Remove any existing burrs on the seat tube of the bike. All parts must be clean during installation! Check before installation that the diameter of the support fits the diameter of the seat tube!

1. by,schulz D.2 ST-Ro seat post provides for the routing of the cable routing outside the frame. As a rule, all bicycle frames / e-bike frames are suitable for the routing of external cable pulls.

The cable guide must not be bent or squeezed along its entire length!

Note: Due to the parallelogram mechanism of the suspension, the D.2 ST-Ro has a greater installation height than conventional dropper posts. Check these requirements with measurement on your bike as accurately as possible in advance.

You should still have a safe stand with the front foot on the ground when the seat post is fully lowered (dimension A) (regardless of the installation depth of the post)!

If the D.2 ST-Ro is fully inserted into the seat tube of the bike and this is not the case, we advise against the use of the support in combination with this bike frame.

Dimension A – Min. body height: approx. 135 mm
Dimension B – Body height extended: approx. 215 mm
Dimension C – Required installation depth: approx. 190 mm
Dimension D – Total length extended: approx. 405 mm

Also note that for the correct seating position, the individual height of your saddle must be added.

Dimensions A, C and D are referred to the center of the saddle clamp. Note that, depending on the frame, an additional approx. 50 mm of installation space is required below the D.2 ST-Ro for the bend of the cable routing!

3. the diameter of the seat tube of your bike / e-bike, should match that of the seat post. Any required reducing sleeves must have a minimum length of 100 mm and must always be fully inserted into the frame.

If the specifications of the frame manufacturer differ with regard to the sleeve length, these must also be taken into account. The higher value is then decisive!

Check whether the minimum insertion depth of the seat post of 100 mm can be maintained!

This is located on the back of the seat post tube as a mark (STOP min. insert) below the extension scale. Above the scale you will find the production serial number.

If the minimum insertion depth specified by the frame manufacturer differs, this must also be taken into account. The higher value is decisive. Failure to observe the minimum insertion depth can lead to falls or damage to the seat post and / or the frame. 6.

The clamping force of the seat post clamp should be 5 – 6 Nm when fixing the post in the frame. If the clamping force values are exceeded, malfunctions such as reduced insertion or extension speed and damage to components of the D.2 ST-Ro may occur. 7.

The D.2 ST-Ro is equipped as standard with a saddle clamp for saddle frames with a diameter of 7 mm. If required, saddle clamps for 8 mm diameter are available. Never combine 7 mm clamps with an 8 mm diameter saddle rail, or vice versa.

Note: Saddles with oval saddle rails must not be installed in combination with this support!

Check that the width of the saddle rail is compatible with the head of the post. It must not be less than 35 mm on the inside. There are some saddles (e.g. core leather saddles) that converge too narrowly in the front part of the frame, and therefore cannot be combined with this post. Such use is not recommended, as it can permanently damage the saddle and the support.

Tech. Data

D.2 ST-Ri:

• Material : Aluminum AL-6061-T6, AL-6066-T6
• Color : Black anodized
• Cable guide : external (Ro)
• Spring element : Length approx. 72mm
• Spring travel : Approx. 30mm
• Body height : Approx. 135mm
• Offset : Approx. 17mm
• Rider weight :
  Ø 30,9 / Ø 31,6 : 115 kg
  Ø 33,9 / Ø 34,9 : 130 kg
• Adjustment Range (Travel) : T80 = Approx. 80 mm
• Bearing / linear guide : IGUS polymer high performance plain bearing/ linear guide
• Diameter : Ø 30,9 | 31,6 | 33,9 | 34,9 mm
• Weight : Weight : approx. 940 g (for Ø 30.9; T80 incl. medium spring)
• Saddle clamp with fine adjustment and robust detent
• For saddle rails with Ø 7mm, optionally available for Ø 8 mm
• Scope of delivery : D.2 ST-Ri seatpost incl. neoprene protective cover and instruction manual incl. cable guide, cable and control lever for mounting on handlebars

D.2 ST-Ro remote lever:

• Material : aluminum AL-6061, black anodized;
  Stainless steel, clamp band, black, screws;
  Plastic components
• Clamp diameter : approx. 22.2 mm
• cable guide radius : approx. 7.5 mm
• Weight : approx. 55 g

The D.2 ST-Ro seatposts are supplied with remote levers matched to the model.
You can recognize the correct design by the laser print or lever radius on the underside.

Cable guide:
• Cable sheath: Jagwire approx. Ø 4.2 mm outside, L = approx.1700 mm.
• Shift cable / inner cable: Jagwire approx. Ø 1.2 mm, L = approx. 1800 mm

Gas spring:
• Maintenance-free by,schulz gas pressure spring

• Spring elements in 4 degrees of hardness for adaptation to rider
to the rider’s weight, easily exchangeable
• Saddle clamp with fine adjustment and robust detent
• For saddle rails with Ø 7 mm, optionally available for Ø 8 mm

Function

The D.2 ST combines the advantages of the lowerable by,schulz D.1 seatpost, with the maximum ride comfort of the renowned G.2 parallelogram suspension seatpost.
The D.2 ST allows comfortable lowering and raising of the saddle position while riding and standing, by means of a remote lever mounted on the handlebars. This allows you to individually take a perfect driving position. The lowering or raising of the saddle is triggered by operating the remote lever.
To lower the saddle height while riding, or when stopping, for example, at a traffic light, stay with your weight on the saddle and operate the handlebar-mounted remote lever.
To activate the seat post extension, unload the saddle by lifting your body and operate the remote lever. The seat post will now extend to the maximum height or stop and remain at the current position when you release the lever,
The speed of this function can be controlled by the intensity of the pressure on the remote lever. Little pressure causes slow extension, strong pressure causes extension at maximum speed.
The parallelogram suspension of the D.2 ST is designed to be progressive, and reacts sensitively to light impacts, and with increasing spring resistance to hard impacts. The parallelogram suspension of the D.2 ST dips under load up to 18 mm to the rear, and about 22 mm downward. For optimum adaptation to the rider’s weight and riding style, there is a choice of easily interchangeable spring elements with 4 different degrees of hardness and damping.
Inside the lowerable D.1 / D.2 seatposts is a high-quality gas pressure spring installed. This allows you to vary the saddle height via a remote lever mounted on the handlebar! When actuating the remote lever, the valve on the gas spring is opened via an internal cable. Thereupon the saddle lowers under load by the body weight, or it extends further when relieved. When the lever is released, the valve closes and the saddle remains at the current height.

Assembly instruction

view here