Meeting by appointment / Termine nach Vereinbarung

Tel. +49 (0)177 7820849 Mo-Fr 10-18 

Jan-Wellem-Str. 23 / D-51065 Köln-Mülheim / Germany


Energize Your Ride

We make lightweight bicycle-electric components 

with high technological and ecological benefits.

Smooth Running, Efficient, Durable. 

Specially developed for commuters, sportive and touring cyclists who need highly durable equipment.

Rim-Drive / Velospeeder E-Bike Motor

Rim-Dynamo / AC-Dynamo for AC-LED-Lights

On-Board Power Supply / Universal Power Source & 3-Phase Geno 

Attention! Velogical products are addictive

Philosophy Tandem Bike Construction

Tandem - Speed


A tandem bicycle glides seemingly effortlessly across the road and then passes easily each individual bike.

On a tandem 2 Pilots actually drive up to 41% faster -

at the same input of energy. The theoretical potential is, however, available on standard models in the market only partially, since important design aspects have been ignored.

With COMPACT tandem now there is an answer to unresolved issues in tandem constructions.


Smooth Running

Wheels of a tandem carry almost double the weight compared to the single bike. Therefore COMPACT tandem has adapted the features of the wheels to match the high downforce:

The 145mm rear hub allows symmetrical spoke structure with reinforced tandem spokes. Extra Width + super stiff rims support the distribution of forces and reduce the rolling resistance in conjunction with an oversized tire cross-section. The tires are optionally configurable for different priorities in road use.

The sports version uses selected brand tires with extremely low rolling resistance while the tour version takes into account the safety.



In the classic seating on the so-called tandem stoker works behind the safe shelter of the captain, who steers the tandem ride on the front seat. Unfortunately this ideal situation exists only as long as the wind is blowing exactly from the front. With the smallest crosswind, this advantage is gone. Therefore: the closer the two drivers sit one behind the other, the less the wind can swirl between them.

COMPACT tandem is very versatile here. Depending on the seat position, handlebar stems and seat geometry, the positions can be customized between speed (narrow, leaning in driving direction flat against the front wind) or comfort (upright, increased sitting distance).





Tandem - Comfort

Of course, a full-suspension bicycle provides a maximum of driving comfort. However, especially in tandem a special rear suspension creates problems related to stiffness and weight. Therefore COMPACT tandem trys to find the best compromise between maximum comfort and reasonably limited technical effort. The delicately appealing, oil-damped suspension fork absorbs effortlessly all the bumps in the road. The rear tire provides with its large air volume for smoother rotation. The rear shocks are absorbed by a saddle suspension of high quality. Although COMPACT tandem was designed more as a fast touring and road vehicle, it makes a good figure on unpaved dirt roads and forest roads, thanks to wider tires and suspension.


Tandem - Overview

short for tight turning circle (width of a park way)

safe in urban use, even on bike paths, ride comfort for two riders on cobble stone pavements and obstacles

solidly constructed lightweight touring bike even full equiped, the design of the drive is optimized designed lo low wear, based on components, that are aviable universally and hardened according tandem requirements,

good speed and hill performance, fits in the luggage space in a station wagon with off-hook quick release wheels - no fiddling with car-mounted carriers,

No disassembly of the frame and chain elements

Handlebar options:

straight front handlebar for sporty riding position

additional second, deeper grip position for rear handlebar


Tandem - Handling


Which tandem rider doesn´t remember it: a chicane, a hairpin or even a wrong turn and U-turn - every time the captain "the curve does not get" the journey is interrupted, the team is maneuvering, until the trip continues again. Blame the extremely large turning circle, driving on a tandem often feel like driving in a long bus. The reason is the large wheel base of actual standard tandem constructions. What do you expect, comparing the wheelbase of usually ca.180cm of standard tandems to a maximum wheelbase of 110cm with a single wheel?


A COMPACT tandem in itself is of course no guarantee of completely uninterrupted roles, but one thing is certain: every inch wheelbase shortened noticeably improved agility and maneuverability. With a wheelbase of 153.7cm COMPACT tandem approaches a technically reasonable lower limit. On a test drive the effect of 26 cm difference in wheelbase is noticable - hairpin curves and U-turns in narrow streets are taken sovereign and quickly forgotten.


During transport in train or car COMPACT tandem makes with 220cm Total length significantly less inconvenience than usual standard tandems with overall lengths of some about 250cm.


If both wheels and seat posts are removed, a COMPACT tandem (with the car´s rear seat folded) fits into any reasonably spacious station waggon. True to the motto "form follows function" using a COMPACT tandem is comfortable. Transport issues  accorrding assembling and disassemblingsof tandems for car transportation now belong to the past.


Weight - Stability - Strength

Image description

These 3 factors contradict each other in frame construction - usually.


COMPACT tandem combines the conflicting requirements in an ideal way. The short tube lengths of a double-butted tube set make the frame "natural stiff". For this purpose the frame is under 4kg and still a lightweight. An elegant strong fork from the trial segment (32mm stanchion diameter) and an extended head tube give the front a solid steering with sufficient safety reserves - even under extreme loads. Stability requirements on a tandem chassis are higher than with suspension forks for standard mountain bikes and trekking bikes. COMPACT tandem is speed compatible, because the effective per weight of the tandem is 18.8kg divided per 2 drivers = 9.4kg - almost the level of classic racing bicycles.