My Gravel Bikes Videos & 6 Observations So Far on Trek’s Checkpoint SL 5

Jim's Tech Talk

By Jim Langley

There's been so much interest in my new gravel bike, a 2023 Trek Checkpoint SL 5 which I reviewed earlier this month, that I wanted to give you more of the story this week – plus some observations and thoughts now that I’ve got some real rides on it. If you missed the review, here's a link: https://www.roadbikerider.com/new-trek-checkpoint-sl-5/.

Some readers got the idea that I was a gravel newbie. So I wanted to explain that while this is my first modern "gravel" bike, it's definitely not my first bicycle that can do what this Checkpoint can, and that riding gravel and dirt terrain on a near-road bike isn't new to me either.

So what I did is make two new videos to tell the whole story of my first "gravel" bike and this new Trek. The first bike, a custom, made for me to my spec by Bonny Doon, California framesmith Jim Oxford is unique and the bike also features some of Keith Bontrager's early innovations. I think you’ll like it. And, in the video about my SL 5, there are some clips of it in action for an idea of what it's like to ride.

I also wanted to pass on – in case you’re interested in a Trek Checkpoint for yourself, that Trek just announced their TrekFest sale. It runs from March 1 to April 2. I don't work for Trek or have any more details about the sale. But it might be worth checking their website trekbikes.com and/or your local Trek dealer to see if you can save on that new G bike or whatever model you’ve got your eye on.

The best thing about riding this gravel bike so far is the ability to hop off the pavement and easily and safely ride on the shoulder when necessary. For example, if an oversize vehicle is passing and the road's too narrow, escaping to the shoulder is a wonderful option that eliminates any risk. Plus, there's some pavement that's so rough that you’ll find riding on the dirt shoulder is smoother, faster and way more fun. Yes, you could probably ride it on your road bike, too, but with gravel tires you’ve got the right rubber and no control or flat worries.

The SL 5 has a storage compartment in the down tube. I’ve seen this on some Specialized brand bikes too. The compartment looks large inside and a Bontrager stuff bag comes with the bike. It has pockets for a CO2 pump and spare tube. I didn't have a CO2 pump with me on my RV trip but I did have a tiny frame pump only 6.5 inches long. I tried to put this and a spare butyl tube inside the bag and into the storage compartment and it didn't fit. I took the pump out and the tube fit fine. My Trek dealer recommended using a TPU spare tube, such as the ones by Tubolito or Schwalbe, which are much smaller than butyl tubes. Here's my review of the Schwalbes. I may do that and I might experiment with either modifying the Bontrager bag or making my own to see if I can get more tools inside the compartment.

Because I have bikes equipped with Shimano Di2 electric shifting I can compare my gravel bike's cable-shifting Shimano GRX drivetrain to it. The biggest difference is that front shifting with a cable derailleur requires pushing the shift lever a long way. I measured the lever throw at the tip to be about 4 inches versus the immediate click of the Di2's button. If you’re used to the super quick front shifts of Di2 you might want to pay more and get a gravel bike with Di2. I don't find that the rear shifting is that different between cable and Di2.

Trek equips the SL 5 with a chain keeper, a small device that prevents the chain from falling off the small chainring. It's become a common feature on lots of bikes, even road racers because as cassettes have gotten more and more cogs, the chain angle has increased a lot, which can cause chain drops. Chain keepers ensure it doesn't happen and they work well. But, it's good to know that if you do happen to drop the chain as I did crashing, that the keeper also makes it more difficult to get the chain back on.

Without a chain keeper you can pedal the chain back on or lift it back on. But the chain keeper will keep the chain from going back on if you try to pedal it back on. So instead you have to create chain slack (push the rear derailleur pulley cage toward the front of the bike), and try to lift the chain or backpedal to get the chain back on. It's not that big a deal but it's not easy like putting a dropped chain on without a chain keeper.

Disc brakes are ultra powerful and usually reliable regardless of where and how you ride. I’ve had them on my mountain bikes since they first came out. So I was more than a little surprised to bend a rotor on one of my first gravel rides. It caused the brake to drag until I got back to the RV and could straighten it with Park Tool's Rotor Truing Fork tool (https://amzn.to/3ZtjjUm). This got me thinking about my old gravel bike with rim brakes. On that bike if I bent a wheel causing the brake to drag, it would be a simple matter to open the brake so it didn't drag. That would be a nice feature for disc brakes to have someday.

So far I haven't had any issues with the Bontrager Paradigm wheels, but a reader named "Agustin" commented that on his Trek Domane with Paradigm wheels he started breaking spokes and on brevets (long important rides), never a good thing. I looked more closely at my Paradigm wheels and from the "S" stamped on the spoke heads, a quick search suggests that these are Taiwanese spokes made by Shuhn Lih Enterprise Co., Ltd. That's not a spoke I have ever built with so only time will tell if I break them, too. If I do, I will rebuild the wheels with DT Swiss spokes, which I trust. And, I will have to take back what I said about the wheels being reliable. (There are actually only a few spoke brands that you can trust, Sapim is another one.)

Jim Langley is RBR's Technical Editor. He has been a pro mechanic and cycling writer for more than 40 years. He's the author of Your Home Bicycle Workshop in the RBR eBookstore. Check out his "cycling aficionado" website at http://www.jimlangley.net, his Q&A blog and updates at Twitter. Jim's cycling streak ended in February 2022 with a total of 10,269 consecutive daily rides (28 years, 1 month and 11 days of never missing a ride). Click to read Jim's full bio.