How do I know if my child's bike is too small?

Riding advice  |  Feb 15, 2022  |  Dave Bowater

You will know it’s time to size up when your bike’s seat post is extended to, or very close to, the “minimum insertion mark”.

When am I ready for a bigger bike?

If you can’t see the minimum insertion mark it is not yet time to size up. To check how much growth-room you have left in your bike, take your 4mm allen key and loosen the seat collar bolt.

Raise the saddle until you see the minimum insertion mark, this is either a white dotted line or stamped mark around the seat post.

Once checked, return the saddle to its correct position and tighten the seat clamp. It’s important not to ride your bike with the seat post extended beyond the minimum insertion mark.

We recommend that the saddle is adjusted so that your child can get the balls of each foot down to the ground on both sides when they are sat in the saddle. If you need more sizing advice contact our customer service team for help.

Help with sizing

Islabikes are carefully sized to ensure they are safe and comfortable to ride.
Find out which Islabike is perfect for you.

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