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Mudguard Installation

This article will guide you through how to install the mudguards on your Polygon Sierra Oosten.


To install your mudguards you will need the 5 to 4 bottom 4mm hex key from the provided multitool in your small parts box, the supplied bolts for mounting the mudguard, which is already mounted in their correct location on the bike, and the mudguard.

Start by removing the two bolts at the bottom of the fork, behind dropouts using the 4mm hex key. Then place the mudguard legs from the back of the fork on the outside of the fork legs.

Now reinstall the bolts with the washer on the outside of the mudguard legs, ensuring the bolts go into the same holes behind the dropout. Next, remove the bolt at the top of the fork arch, there should be one bolt, one nut, and two washers. Then line up the mudguard attachment plate with the hole at the back of the fork. 

Now reinstall the bolt with the head at the front of the fork with one washer and then install the second washer on the outside of the attachment plate at the back of the fork and then the nut.

Then tighten the bolt with the 4mm hex key and hold the nut. This doesn’t need to be overly tight.

Congratulations, your mudguards are now installed. Feel free to contact us in case you have any questions or concerns and happy riding!


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