What frame size do I need?

Your inseam length and body height are usually a good starting point. We provide an initial recommendation on each product page. If you’re between two sizes, the smaller size feels more agile and sporty, while the larger size offers a calmer and more comfortable ride. However, many factors come into play when choosing the perfect bike. We always recommend a test ride.

What is a virtual frame height?

Traditionally, bikes had horizontal top tubes. Frame height was the distance between the bottom bracket and the point where the seat tube and top tube meet. Some of our frames have a sloping top tube. This design makes it more comfortable to wait at a stoplight, for example. However, the geometry is still determined by the point where the seat tube and a horizontal top tube would intersect. The distance from this point to the bottom bracket is the virtual frame height.

Which dealer is near me?

We have over 500 specialist dealers in various European countries. We recommend using our dealer search tool, where you can find all nearby dealers.

Go to Dealer Search

Which bikes does my local dealer have in stock?

For most of our dealers, we can show availability directly in our dealer search tool, as they share their inventory with us. For some dealers, this is not possible, and you’d need to inquire directly. We are constantly working to expand this coverage.

Does Diamant offer factory sales or sales of B-stock or demo bikes?

We do not offer factory sales. B-stock items do not pass our quality control. Our demo bikes are sold directly to dealers, who must refurbish them for general use. Therefore, we recommend visiting one of our 500+ specialist dealers—there’s likely one near you.

In which countries are Diamant bikes sold?

Diamant distributes bikes to dealers in Germany, Austria, and Switzerland. As of 2025, we’ll also be present in Belgium, France, the UK, the Netherlands, and Poland. Some of our dealers offer online shipping to other countries. In some countries, we also offer e-commerce through trekbikes.com.

I’d like a different color or I’d like to change some parts. Is that possible?

Our manufacturing process doesn’t allow for customizations beyond the options available on our website. We select configurations that we believe make the best bike for most customers. As a result, we offer a limited range of color options. For technical adjustments, your local dealer can advise and assist you. Note that dealers do not exchange parts free of charge.

Can I trade in my old bike?

For purchases made through our e-commerce system, we do not offer trade-ins. For purchases from a dealer, please inquire directly with them.

What is the maximum system weight of my bike?

We specify the maximum weight (bike, rider, luggage, including clothing, lock, water bottles, etc.) on each product detail page. Typically, this is 136 kg for bikes without motors and 136 kg or 160 kg for our e-bikes.

What happens if I exceed the weight limit for the bike or rack?

Your bike won’t fall apart immediately but wear and the risk of sudden damage under heavy loads will increase. For legal reasons, we do not recommend exceeding the maximum system weight or the carrying capacity of your rack.

How far can I ride my e-bike?

The range of your e-bike depends on factors like weather, weight, terrain, road quality, your speed, and riding style. While we can’t provide a general answer, we collaborate with Bosch to offer a range calculator that estimates the range based on your personal circumstances.

Go to Bosch Range Calculator for Diamant

How quickly can I charge my e-bike battery?

The larger the battery, the slower it charges. With Fast Charge, a 545-Wh Bosch battery takes just over 90 minutes for a 50% charge and about five hours for a full charge. Larger 800-Wh batteries charge to 50% in about 2.5 hours and take around 7 hours for a full charge with the 4A Charger. We ship our e-bikes with the fast 4A Charger to save you time.

For more details, check our article on e-bike battery charging and see an overview of all charging times in Bosch’s simple table.

How many charge cycles does my e-bike battery have before needing replacement?

Bosch’s Battery Management System protects your battery from premature aging. You can charge your battery as often or as little as needed without affecting its lifespan. After 500 complete charge cycles, your battery will still retain about 70% of its original capacity.

Which charger can I use?

Bosch offers three different chargers with varying charging speeds. To avoid damage, only use original Bosch chargers. All our e-bikes with Bosch motors come with the fast 4A Charger, saving you many hours of charging time.

Should I always fully charge the battery?

If you’re storing the bike for an extended period, Bosch recommends a charge level of 30-60% (two to three lit LEDs on your battery indicator). For shorter storage times, you can deviate from this.

Can I store my bike in the garage for a long time?

E-bike batteries are best charged and stored at room temperature in a dry environment. Room temperature is ideal for all our bikes. For more details, see our article on storing and maintaining e-bike batteries.

Can I replace my old battery with any compatible battery?

The warranty on your e-bike is valid only if the bike is used as we deliver it. Modifying the specifications voids the warranty. With batteries, we are strict—no exceptions. As these are sensitive components, we don’t approve third-party batteries for our products.

Can I modify or upgrade my e-bike?

Our e-bikes are certified with a CE mark, which confirms that the product complies with EU safety, health, and environmental protection regulations in its standard configuration. Modifications can void warranties and insurance coverage. Check with your national guidelines for component replacements and pay attention to differences for pedelecs (up to 25 km/h assistance) and speed pedelecs (up to 45 km/h assistance).

Can I convert my pedelec to a speed pedelec?

Speed pedelecs require a license plate in most countries and must meet stricter requirements than standard e-bikes.

Where can I find the user manual?

We provide user manuals for all models since 2015 on a dedicated webpage.

All Manuals

Which child seat can I attach to my bike?

Römer child seats are compatible with most of our bikes, provided you respect the maximum system weight. They are not compatible with e-bikes featuring a rack battery or bikes with carbon seat tubes. Bikes with an MIK-HD rack can accommodate compatible child seats directly on the rack. Always observe the maximum system weight and rack capacity of 27.5 kg. For other seats, consult the manufacturer directly.

My Diamant bike has no rack or mudguards. Can I add them?

In principle, racks and mudguards can be retrofitted on all Diamant bikes with the necessary mounting points. However, ensure there is enough clearance between wheels and other parts. In some cases, thinner tires may be required. Your dealer can advise you further.

Can I register my bike with the police?

Bike registration allows a bike to be uniquely associated with its owner. You can register your bike on our website using the frame number on the sticker on the downtube (starting with WTU). On request, we assist the police with ownership verification, even without additional coding. If you still wish to code your bike, be aware that methods such as engraving or needle marking can damage the frame’s finish, potentially leading to corrosion or paint chipping. We recommend adhesive labels as a non-invasive alternative.

My bike is not working properly. Who can I contact?

Your first point of contact is the Diamant dealer where you purchased your bike. They are responsible for your dealer warranty claims. After your dealer warranty period has expired, you can visit any Diamant dealer. They can professionally inspect the bike and, if necessary, handle the manufacturer warranty process with the appropriate contact person. Be sure to also review our detailed warranty terms and conditions.

Warranty regulation

How do I submit my warranty claim?

When you purchase a bike, you enter into a contract with the dealer. They are responsible for the statutory seller warranty. Therefore, you must always contact the Diamant dealer where you bought the bike first. The dealer will assess whether the issue falls under seller warranty or manufacturer warranty. The manufacturer warranty may complement the seller warranty if applicable. If your dealer determines it might be a warranty case under the responsibility of the manufacturer, they will submit a warranty request to us. We will then review the request and decide on the guarantee.

Why can’t I submit my warranty claim directly to you?

We always need a professional assessment to decide on warranty cases. For this, we rely on the expertise of our local dealers. We believe this approach is more ecological and efficient. In some cases, we may still want to inspect the issue ourselves. In such instances, we handle shipping from the dealer to our assigned customer care team and back.

Why was my warranty claim rejected?

In rare cases, we need to reject warranty claims, typically for one of these three reasons: (1) There is a violation of the warranty terms, particularly regarding damage caused by normal wear and tear or improper use. (2) Required documentation, such as proof of purchase, is missing and cannot be provided even upon request. (3) The dealer’s statutory seller warranty obligation still applies, as it takes precedence over the manufacturer warranty.

Who is my contact person if I purchased my bike from an online retailer?

Your first point of contact is the online retailer where you bought your bike. They are responsible for claims against your dealer’s seller warranty. After the seller warranty period has expired, you can visit any Diamant dealer. They can professionally inspect the bike and, if necessary, handle the manufacturer warranty process with the appropriate contact person.

My dealer is refusing the statutory seller warranty. What should I do?

We cannot provide a general statement on this matter. However, we are happy to assist in individual cases by mediating between the customer and the dealer. Please feel free to contact us.

Our (toll-free) phone number: 01908 360140
You can find our contact form here.

Can I go to any Diamant dealer for warranty and guarantee?

Within the statutory seller warranty period, you should always go to the Diamant dealer where you purchased the bike, even if they no longer sell Diamant bikes. Afterward, we recommend the same approach for the guarantee. However, once the dealer’s warranty obligation has expired, you can contact any Diamant dealer for warranty-related matters. If your dealer no longer exists, you can also visit another Diamant dealer. Please never go to a dealer who does not sell Diamant bikes.

What is the difference between statutory seller warranty and manufacturer warranty?

The statutory seller warranty is a legal right you have against the seller, who in your case is the dealer where you purchased the bike. The seller warranty ensures that the bike is free from material and legal defects at the time of purchase, even if these defects become visible later. The manufacturer warranty, on the other hand, is a voluntary service offered by us as the manufacturer. There is no legal right to the manufacturer warranty. The manufacturer warranty cannot reduce or replace the statutory seller warranty; rather, it serves as an additional benefit.

I would like to speak with your customer service. How can I get in touch with you?

You can reach us through our contact form or by phone. Please note that we share resources with our parent brand Trek. Don’t be confused if you hear a voice on the phone representing Trek.

Our (toll-free) phone number: 01908 360140
You can find our contact form here.

I have had a crash with my bike. Does Diamant offer a crash replacement program?

Accidents happen. Unfortunately, damage to the frame or fork from a crash is not covered by the warranty. However, in such cases, we offer a goodwill program. We provide you with a discount on a new complete bike. If we also sell frame sets for your bike, we can alternatively offer a discount on the frame set. Please note that we do not cover any potential workshop costs.

How can I obtain spare parts for my Diamant bike?

We keep spare parts in stock for an extended period and will reorder them if needed, as long as the supplier is still available. Unfortunately, we cannot guarantee this indefinitely. Therefore, we may not always be able to provide an identical spare part. However, we will always offer a solution so that you can continue riding. Diamant-specific or alternative spare parts can be easily ordered through any Diamant dealer. We recommend one of our over 500+ specialist dealers – there is likely one near you.

Does Diamant grant a warranty on used bikes?

Our warranty, including the lifetime frame warranty, is offered to all first owners. Unfortunately, it does not apply to used Diamant bikes. Exception: We provide a limited warranty for second owners on used bikes if the original sale was no more than three years ago.
For more information on our warranty terms, you can find details here.

How can I find the serial number of my bike?

Your serial number is the WTU number on the overlaid sticker on the downtube. You can usually find it again on your invoice as well.

What do the two WTU numbers on my bike mean?

The WTU number on the overlaid sticker on the downtube is the serial number of your bike. The engraved WTU number on the bottom bracket is an internal production number, which is not relevant to you.

I have paint damage on my bike – how can you help?

We offer specific touch-up paint for many of our current bikes to repair small paint damage. You can either order these through your Diamant dealer or purchase them directly online at trekbikes.com. If we don’t offer touch-up paint for your specific color, we recommend contacting a car painter. They can derive the color code from your bike on-site and mix the appropriate replacement paint. This ensures the best match, as some colors may fade slightly over time due to sun exposure.

Why can’t I turn off the light on my e-bike when the motor is on?

Your Diamant is configured by default so that you cannot turn off the light when the motor is on. Always-on lights are, for us, a good argument for greater safety in electrified road traffic. This has no significant impact on your range. However, if you want to control the light yourself, your Diamant dealer can enable this option via software.

How old is my Diamant bike?

For bikes manufactured before 1991, you can determine the year of manufacture from the serial number. After the company was acquired by Villiger in 1992, our marketing team can assist with identifying the year using historical catalogs. If your bike was built after 2004 and has a WTU number, our customer care team can deduce the year of your bike from it.

For more information on dating our historical bikes, check out the DDR Fahrradwiki.

You can contact our Customer Care team through our contact form.

Do you have detailed information about your historic bikes?

We have already featured some iconic Diamant bikes in our blog. Additionally, we offer an archive of our recent catalogs on our German website. If you have older catalogs, feel free to send them to us—we’d be happy to digitize and re-publish them online. Our anniversary book for our 125th birthday also contains a lot about our old bikes, and we offer it for free on our German website. Good sources for historical Diamant bikes are collector websites like the DDR Fahrradwiki or the comprehensive book on Diamant’s history by Werner Aidn.

Is there an exposition of historic Diamant bikes?

Yes, there are a number of museums that display a few highlights from Diamant. We happily invite you to visit the Museum für sächsische Nutzfahrzeuge Chemnitz. They feature a comprehensive variety of historic bikes within the permanent exposition. You’ll learn more about Diamant and the other manufacturers that once made Chemnitz the most important place in German vehicle and bicycle production.

Is my old Diamant bike historically interesting or valuable?

From our perspective, every old bike is valuable. We cannot assess the market value of a used or historic bike on a case-by-case basis. For newer bikes, you’ll need a dealer to evaluate the condition. For truly old bikes, other factors come into play: Do you know more about the bike’s specific history? Is the bike in good condition? How much has it deviated from the original? Unfortunately, we cannot provide this evaluation ourselves.

Would Diamant buy my old Diamant bike?

Unfortunately, we do not have the space or resources to professionally restore, store, and exhibit historical bikes. Therefore, we do not buy historical bikes.

Since when has Diamant been making bicycles?

Diamant has been manufacturing bicycles since 1895. Since then, all Diamant bicycles have been assembled in Germany—initially in Reichenbrand near Chemnitz and, since the mid-1990s, in Hartmannsdorf. No other German bicycle brand has such a long and continuous manufacturing history. Internationally, only the two Italian brands Bianchi and Olympia have a longer continuous and self-controlled manufacturing history than Diamant.

Why is Diamant named after the gemstone?

There’s no certainty, but only a historical assumption regarding this. Diamant was originally named after the founding family, i.e. the Nevoigt brothers. At the beginning, they produced parts for knitting machines and nibs for fountain pens. These nibs were made from a particular steel branded as “Diamant steel.” We assume that the company went on to use the same steel for their bicycles – and thus the name was born.

Why does the Diamant logo feature a stylized head instead of a diamond?

Before World War I, Diamant established its first racing team, spearheaded by the company’s first sales director, Albrecht Spremberg. The logo, featuring a chubby head, first appeared on the racing team’s bikes. It is rumored to be a likeness of Mr. Spremberg himself. This anecdote led to the creation of one of Germany’s most enduring logos, which is now over 110 years old.

Are Diamant bikes just rebranded bikes from Trek?

We develop all current Diamant platforms 100% exclusive for Diamant. No Trek bike will use these same platforms. However, in the past, Diamant and Trek did indeed share many frames. In most of these cases, they were developed jointly, and Diamant’s product management routinely took the lead when a platform was mostly relevant for the German-speaking market. When we used shared frames, specifications and components would distinguish Diamant and Trek, and at Diamant we often built bikes with more pre-assembled equipment like fenders, kickstands, dynamo lights, and racks.

Is every “Diamant” bike a Diamant bike from Hartmannsdorf?

No. Until the early 2000s, there was a Belgian bicycle brand also called Diamant. Some of their race bikes still pop up here and there. The biggest and oldest bike manufacturer in Norway is also named Diamant, and in France, there was La Française Diamant, active until the 1950s and known for participating in the Tour de France. These brands were always independent of our Saxonian Diamant.

Is there a contact for marketing partnerships and press inquiries?

For marketing collaborations and press inquiries, you can contact our marketing team directly at marketing@diamantrad.com. For technical questions, we recommend using our contact form to connect with customer service.

Go to the contact form.

Does Diamant offer factory tours in Hartmannsdorf?

Currently, we do not offer factory tours in Hartmannsdorf. If this changes, we will inform you through our newsletter.

Are all Diamant bikes made in Hartmannsdorf?

All Diamant bicycles are assembled in Hartmannsdorf. Each Diamant bike is still handcrafted there. The components are sourced from external partners whom we trust to meet our quality and environmental standards.

Are Diamant bikes just rebranded bikes from Trek?

All new Diamant platforms from 2025 onwards are 100% engineered for Diamant. No Trek bike will use these same platforms. In the past, Diamant and Trek did share many frames. In most cases, they were developed jointly, and Diamant’s product management routinely took the lead for developments with greater relevance for the German market than other markets. Specifications and components distinguished Diamant bikes and Trek bikes on the same platform, and Diamant often built bikes with more equipment like fenders, kickstands, dynamo lights, and racks.

I’d like to work for Diamant. Where can I find information on career opportunities?

We have a career section on our website, where you can learn about all the opportunities and locations to work with us. Most of our employees work out of Hartmannsdorf, but some of our functions are located elsewhere in Germany and in Switzerland and Holland, sharing their offices with our peers from our parent brand Trek.

Explore career opportunities at Diamant.

Will Diamant ever build a road bike again?

We assemble road bikes every day—for our parent company Trek. Seriously though, we find the topic fascinating and enjoy sporty rides ourselves. We understand the special memories tied to our historical road bikes and are proud of the achievements they enabled. From that era, we gained significant experience. However, during the later DDR era, we lost ground due to limited resources. Today, developing road bikes is complex. There’s little demand for a road bike that doesn’t distinctly stand out from established brands. We believe we can best carry on with what we are excellent at: bikes for leisure, commuting, and every day. But we still have many years ahead of us—someday, we’ll be 167 years old!