Owner's manual – Mechanical work warning

A warning about mechanical work and modifications

When to do it yourself, when to consult a pro, and when not to do it at all. Please read this information carefully before doing any work on your bicycle.

Bicycles are super fun to ride, but they can also be super complex pieces of machinery. Just like you’d call a plumber to fix a busted pipe or take your car to a mechanic to replace the brakes, it’s important at times to take your bike to a professional bike mechanic.

Performing mechanical work on bicycles

Do not perform the tasks in these pages if you do not have the correct tools or experience. Instead, take your bicycle to your bike workshop for service.

Although we cover a lot of helpful information, we don’t tell you everything you need to know to work on your bicycle. Some tasks should only be done by your retailer, and we’ll identify them here.

⚠ WARNING: Many bicycle service and repair tasks require special knowledge and tools. Do not begin any adjustments or service on your bicycle until you have learnt from your bike shop how to properly complete them. We recommend that significant mechanical repairs be carried out by a qualified bicycle mechanic. Improper adjustment or service may result in damage to the bicycle, or an accident that can cause serious injury or death.

Assembling your bicycle

Special tools and skills are necessary for the assembly and the first adjustment of your bicycle. Only your bike shop or a qualified bicycle mechanic should do this.

If you purchase only a frame set (frame, fork and headset), anything other than the parts we specify would be considered a modification. Consult your bike shop to make sure all the parts you have chosen are compatible and that you have the correct tools and skills to complete the assembly in a safe manner.

Modifications or changes to your bicycle

Modifying the parts of your bicycle in any way can make it unsafe. This includes altering existing parts, adding parts or accessories, or swapping out original parts for non-original ones. Any other modification of your frame, fork or components means that your bicycle no longer meets our specifications and will void the bicycle's warranty.

There are too many modifications to list them all, but here are a few examples of unauthorised, unsafe modifications:
• Removing paint can weaken the frame because some bicycle frames have special surface treatments which add strength.
• Removing the redundant wheel retention tabs on fork tips could make your bicycle less safe.
• Adding spacers, washers, etc. to a wheel quick-release device decreases the thread engagement of the adjusting nut.
• Installing a part not authorised for your bike can damage other parts. For example, a stem not approved for a carbon steerer tube can crush the steerer tube.
• Installing a motor or other drive system adds weight to the bike and causes stress to the parts. Adding non-approved parts will void the warranty and make the product unsafe.

⚠ WARNING: Any unapproved modification can make your frame, fork or part unsafe. For your safety, do not sand, drill, file, remove secondary retention devices, install incompatible forks or make other unapproved modifications. A frame, fork or component with unapproved modifications may decrease your control and cause you to fall. Before you modify or add an accessory to your bicycle, consult your retailer to confirm that it is compatible and safe.

Adding accessories to your bicycle

You may choose to add accessories to your bicycle, like mudguards, racks, aerobars, child carriers, etc. But not all accessories are compatible or safe, so only add a part or accessory that has the approval of your Trek bike shop.

If you mount an accessory to your handlebar, such as lights, computers, etc., make sure it is secure before riding. If an accessory falls from your handlebar, it could become entangled in the spokes of the front wheel and cause an abrupt stop. If a light or computer is connected by a wire to the frame or fork, the risk of it getting caught in the spokes is greater.