John 'Zac' Brennan

Cancer is the biggest killer of kids from disease in the USA, 38 children die every week. Please donate now and support my challenge to fight kids' cancer!

Donate Now

I've Ridden 0.0 mi My goal is 200 mi

My Rankings

National: 638th
State: 16th in CO
My Team: 9th

I've raised $307 My goal is $500 Donate Now

I'm Riding For

Kahleesi

Kahleesi ride your cool bike! Have fun❤️

My Story

16 Aug 2026

This September 2026 I am taking part in the Great Cycle Challenge to fight kids' cancer!

Cancer research funding has been recently defunded by the current administration in Washington. Now, more than ever the children née our help.

Why? Because right now, cancer is the biggest killer of children from disease in the United States. Over 15,700 children are diagnosed every year, and sadly, 38 children die of cancer every week. Kids should be living life, not fighting for it.

So I am raising funds through my challenge to help these kids and support Children's Cancer Research Fund to allow them to continue their work to develop lifesaving treatments and find a cure for childhood cancer.

Please support me by making a donation to give these kids the brighter futures they deserve. I'm also riding for myself. In Vietnam in the Army I was exposed to Agent Orange herbicide and now at 76, have Stage IV metastatic prostate cancer.

Your support will change little lives.....and mine too!

Thank you.

John Zac Brennan

My Legacy

Here's my personal impact over 7 years to fight kids' cancer and save little lives.

514 mi Ridden

$2,077 Raised

2020
465 mi Ridden

$1,695 Raised

2021
519 mi Ridden

$2,266 Raised

2022
546 mi Ridden

$6,000 Raised

2023
565 mi Ridden

$4,500 Raised

2024
534 mi Ridden

$4,240 Raised

2025
Ridden

$307 Raised

2026

3,144 mi

Ridden

$21,085

Raised

My Challenge

$250 raised to fight kids' cancer!

I just raised $250 to fight kids' cancer and achieved PROTECTOR LEVEL in the challenge! Thank you so much for your support.

Posted 3 days ago
$100 raised to fight kids' cancer!

I just raised $100 to fight kids' cancer and achieved DEFENDER LEVEL in the challenge! Thank you so much for your support.

Posted 29 days ago

My Sponsors

Christopher Flanagan
$103.50
Received this donation 8 days ago

John

“Chris, Thank you for your support. I’m gearing up for next month’s Ride. Been riding when the heat relents. A few mornings and evenings. My legs are good ,it’s the smoke that’s reduced my normal ride levels this Spring/Summer. I’m coming to Junction Monday afternoon, August 24th. Oral surgeon follow up visit Tuesday am. I would like to get together. Dinner Monday? Brunch Tuesday? Lemme know”

Chris, Thank you for your support. I’m gearing up for next month’s Ride. Been riding when the heat relents. A few mornings and evenings. My legs are good ,it’s the smoke that’s reduced my normal ride levels this Spring/Summer. I’m coming to Junction Monday afternoon, August 24th. Oral surgeon follow up visit Tuesday am. I would like to get together. Dinner Monday? Brunch Tuesday? Lemme know
Tom Schreiber

“Tom, Thank you for your kind donation. The heat has broken and I’m pumped to ride and raise bucks for the kids. My miles don’t officially count until September 1st. Then my initial goal is 200 mil for a start. Typically it ends up over 500 miles. This is my 7th year of participating. I’m stoked!!”
$100
Received this donation 3 days ago

John
John 'Zac' Brennan

“Time to kick off my fundraising efforts! I’m down for $100 to get things started.”
$103.50
Received this donation 29 days ago

John