How Well Do Bike Tires
Grip Different Surfaces?

A Friction Science Experiment

By: ________________________________

School: ________________________________

Date: ________________________________

Grade 1

PURPOSE

Why did we do this experiment?

We wanted to find out which surfaces make bike tires grip the best.

Sometimes bike tires slip. This can be dangerous!

We wanted to learn:

Which surfaces are safe to ride on?
Which surfaces are slippery?
What is friction?

HYPOTHESIS

What did we guess? (Our hypothesis)

We thought that:

Rough surfaces (like sandpaper) would grip better. The tire would not slide easily.

Smooth surfaces (like plastic) would be slippery. The tire would slide easily.

"If the surface is rough, the tire will grip better."

BACKGROUND RESEARCH

What is Friction?

Friction is a force. It happens when two things rub together. Friction slows things down or stops them from sliding.

Why do bikes need friction?

Friction helps bike tires grip the road. Without friction, tires would just spin and slide!

Rough or Smooth?

Rough surfaces have more friction (sandpaper, carpet)
Smooth surfaces have less friction (ice, plastic)

How do we test friction?

We use a ramp. We lift one end slowly. When the tire starts to slide, we measure the height. Higher number = more friction!

DATA & RESULTS

Materials We Tested:

Sandpaper (rough)

Carpet

Cardboard

Paper

Wood

Plastic (smooth)

Our Measurements:

Surface	Test 1 (cm)	Test 2 (cm)	Test 3 (cm)	Average (cm)
Sandpaper
Carpet
Cardboard
Paper
Wood
Plastic

Higher number = more friction = better grip!

Our Graph:

HOW WE DID IT

Our Steps:

Step 1: We put a surface on the board.

Step 2: We put the tire block on top. Weight: _______ g

Step 3: We lifted one end of the board slowly.

Step 4: When the tire started to slide, we measured the height.

Step 5: We did this 3 times for each surface.

Photos:

RESULTS

What did we find out?

The surface with MOST grip:

_______________________

Height: _______ cm

The surface with LEAST grip:

_______________________

Height: _______ cm

Ranking (best grip to worst):

1. ___________________

2. ___________________

3. ___________________

4. ___________________

5. ___________________

6. ___________________

CONCLUSION

Was our hypothesis right?

☐ YES! We were right.

☐ PARTLY - Some things were different.

☐ NO - We were wrong.

What did we learn?

Rough surfaces have more friction. They grip better.
Smooth surfaces have less friction. They are slippery.
Friction keeps us safe on a bike!

What surprised us?

_________________________________________________

Real life:

Bike tires have treads (patterns) to make more friction!

Be careful on smooth or wet surfaces - less friction!