Das Zedler-Team

Annelies Rokitte-Elmering has been heading administration in the Product Testing area since 2014 and is your contact person for all organisational questions relating to your test.

Before that, the humanities graduate worked in international PR and as a freelance translator. Today she uses her language skills when dealing with international customers.

She also keeps active in her free time, ideally on her bike or out hiking.

Since autumn 2024, Lars Oefinger has been a student at Baden-Wuerttemberg Cooperative State University Stuttgart (DHBW), where he is enrolled in the bachelor’s programme “Industrial Engineering”.

He completes the practical part of his studies in the testing department team at the Zedler-Institut. Here he is involved in quality assurance in the laboratory, where he works on the calibration of measuring equipment and, naturally, on the planning and business side of building test systems.

Running is part of his everyday life, and he likes to spend his weekends hiking in the mountains.

Norman Thalheimer came to the Zedler-Institut through his bachelor’s thesis: as part of his mechanical engineering studies at Aalen University, the trained industrial mechanic designed a test rig for the fatigue strength of wheels together with the team.

Since 2015, he has been heading the testing laboratory and is your contact person when it comes to carrying out your testing assignments.

Away from the laboratory, the family man can be found on the climbing wall, on his bike or playing the trombone.

Julius Weimann has been part of the Zedler team since 2016, where he carries out testing assignments in the laboratory, programmes the testing machines and manages incoming goods.

The graduate engineer (Dipl.-Ing. FH) already wrote his diploma thesis at the University of Applied Sciences Würzburg-Schweinfurt on the load-appropriate design of bicycle rims made of fibre-reinforced plastic.

He cycles to work almost every day, which doubles as his training for his next triathlon. His free time belongs entirely to his children, who keep him at least as busy as any endurance test.

From the bike shop to the testing laboratory: David Heil was already working on bikes in a bike shop while still at school, before completing his apprenticeship as a bicycle assembler at the Zedler-Institut.

Since 2011, he has been supporting the engineers in the laboratory, preparing test specimens and overseeing the tests on the machines.

With more than 15 years of experience, he knows exactly what matters in every test. In his free time, he enjoys heading out with his camera to shoot videos or take photos.

Anyone with as many bicycles in the basement as Rainer Aisenpreis is in exactly the right place in the Zedler team.

The long-time cyclist already had friendly ties with the Institut before he joined permanently in 2017 after many years in various trades.

Since then, he has been supporting the test engineers in the laboratory and taking care of the building services.

Philipp Kipker wrote his master’s thesis on factors influencing braking behaviour in the testing team at the Zedler-Institut.

A mechanical engineering graduate of Clausthal University of Technology, he has been a permanent member of the team since 2018. Today he heads quality assurance and oversees the accreditation of the testing laboratory. He also continuously drives forward the optimisation of the laboratory information management system. This makes him your contact person for all questions relating to quality and test procedures.

In his private life, the long-time mountain biker enjoys riding off-road and is increasingly taking part in triathlons as well.

Julian Großkopf first came into contact with the Zedler-Institut during an internship lasting several months in 2018.

Today he works part-time in quality assurance in the testing laboratory. He completed his bachelor’s degree in Aerospace Engineering at the University of Stuttgart in 2024 and is currently deepening his knowledge in a master’s programme, which he expects to complete in spring 2028.

Since the 2025 season, he has been competing with a professional licence from the German Triathlon Union (DTU). At the 2026 Berlin Marathon, he ran a time of 2:15:24, making him the German triathlete with the fastest marathon time.

The Zedler-Institut has been supporting him since 2021 with clothing, fast bikes and equipment for training and competition in triathlon and running.

Fynn Heit came to the Zedler-Institut through an internship in the testing workshop. Here he completed his apprenticeship as a bicycle assembler and then trained as a two-wheeler mechatronics technician specialising in bicycle technology.

Since April 2026, he has been a permanent member of the team, taking care of dismantling, assembling and repairing bicycles and complex e-bike systems, all the way through to setting up our test systems.

The development and design of our static and dynamic test systems is the core area of Frank Leyrer, who has headed the department since 2004.

The mechanical engineer already gained experience in building test rigs during his dual study programme at a renowned automotive supplier.

In his free time, he swaps his design desk for his mountain bike, gravel bike and road bike.

In the mechanical workshop, Jürgen Haag manufactures parts for our test systems and helps build them. He also carries out testing assignments in the testing laboratory.

A trained industrial mechanic specialising in precision engineering and instrument making, he joined the Zedler team in 2010 after working for many years as a team leader at a metalworking company.

Even after work, he can’t get away from bicycles: whether on his mountain bike or road bike, he not only loves riding but also builds his bikes himself.

After finishing secondary school, Louis Pflugfelder spent a voluntary ecological year working in landscape conservation and nature protection before starting his studies in Mechanical Engineering with a specialisation in Design and Development at DHBW Stuttgart in October 2026.

He completes the practical part of his studies at the Zedler-Institut, where he mainly supports the test engineering team in designing, expanding and optimising the test rigs.

Digitally mapping workflows in testing: that is what Kilian Seelbach has been taking care of as a working student in the Zedler team since September 2025.

He is also the contact person for all technical IT questions in-house. Alongside his studies in Digitalisation and Information Management at Hochschule für Technik Stuttgart, he brings experience from his apprenticeship as an industrial electronics technician, which he completed with distinction in 2020 at a renowned automotive supplier.

In the mornings, he cycles to work. After hours, he swaps the keyboard for a volleyball or his electric guitar.

Sebastian Martin brings more than 13 years of experience as an assessor: since 2013, the Bachelor of Science has been preparing expert reports as an expert in the Damage Assessment area and helps you with all questions relating to technical evaluation.

He has known the bicycle industry since his training days, when he worked in maintenance and servicing in the bicycle trade. He then spent two years working as an industrial technologist in mechanical engineering at a large technology group.

In his private life, he is drawn to the outdoors: on his road bike, on his mountain bike or on bike tours with his family, in his running shoes or on hiking trails.

As an expert in the Damage Assessment area, Manuel Gönnenwein has been preparing expert reports since 2019 and is your contact person for all questions relating to technical assessments.

His interest in vehicle engineering with a focus on bicycles already shaped his mechanical engineering studies at the University of Stuttgart, which he completed with a Master of Science.

In his free time, he devotes himself to winegrowing, plays the tuba in a brass ensemble and enjoys tinkering with wood and other materials. On good days, he often simply cycles the 25 kilometres t

Since 2002, Timea Markel has been keeping an eye on processes at the Zedler-Institut.

She handles orders in the Damage Assessment area, organises our workshops and is your contact person for everything that comes up before and after an assessment. Thanks to her many years of experience in the freight forwarding industry, she also takes care of national and international bicycle transport.

To unwind, she sits down at the piano, picks up a good book or starts planning her next trip.

Arne Macher learned his craft right here at the Zedler-Institut: after an internship in the testing workshop, he completed his apprenticeship as a bicycle assembler and then trained as a two-wheeler mechatronics technician specialising in bicycle technology.

Today he dismantles, assembles and repairs bicycles and complex e-bike systems and prepares them for the test systems.

Away from the workshop, he enjoys getting in the saddle himself or spending time outdoors with friends.

Petra Grunewald has been heading the Conformity Assurance department since 2008. She is your contact person when it comes to instruction manuals, conformity checks and risk assessments.

Before that, she worked at the Fraunhofer Institute for Industrial Engineering IAO in the field of ergonomics and work science, as well as an editor in e-government.

In her free time, she enjoys going for runs or heading out on her bike.

Since 2015, Kirsten Krümmel has been making sure that instruction manuals, presentations and printed materials not only inform but also look good.

A trained media designer, she learned her craft as a graphic designer at agencies and publishing houses in Nuremberg.

She also cycles to work every day. She spends her days off hiking or riding her bike, ideally with a stop for a cup of coffee along the way.

Since autumn 2024, Lisa Perikic has been a student at Baden-Wuerttemberg Cooperative State University Stuttgart (DHBW), enrolled in the bachelor’s programme “Business Administration, International Business”.

She completes the practical part of her studies at the Zedler-Institut. She supports the Ensuring Conformity team with the commercial processing of orders and projects and takes care of the social media channels.

The face of the Institut is our founder. The graduate engineer is a publicly appointed and sworn expert for bicycles and electric bicycles (Stuttgart Chamber of Industry and Commerce, IHK), a member of the DIN standards committee, and founder and since then deputy chairman of the board of the association Zukunft Fahrrad e.V.

Many cyclists also know him from his 25 years of work with the cycling magazine TOUR, where he was responsible for the legendary workshop series, among other things. Since founding the company in 1993, the still active sportsman has been doing everything he can to make bicycle products more functional, more durable and therefore safer, to bring more professionalism to the bicycle industry and to raise the standing of bicycles, pedelecs and cargo bikes.

He finds balance to his everyday work in cycling and model making, where his passion for technology and precision lives on after hours.

Accounting, finance and HR matters are in the hands of Claudia Zedler, who has been responsible for these tasks at the Zedler-Institut since 2010.

Before that, after completing her vocational training, she worked for many years at large companies, both in office roles and in quality assurance.

In her free time, she is out and about on her road bike or mountain bike. On days with bad weather, she indulges her passion for textile handicrafts.