SKS Explorer Top Tube Bag and Smartphone Holder is Smarter than it Looks [Review]

There are top tube bags, and then there is the SKS Explorer top tube bag. It boasts not just one but two zippered, waterproof compartments, a see-through plastic top for use with a smartphone, and a port for charging your phone or plugging in headphones on the go. I tested one over three days and 340 miles of bikepacking and found it to be quite functional.

Size and weight

I decided to load up the SKS Explorer with my phone, camera, a face mask, an extra battery, and snacks for easy access during the day. The top tube bag is in the perfect position to be accessible and to keep the phone clearly visible while riding.

The SKS Explorer has two compartments; the top one is about 40mm tall (1.5in) and is meant to hold a smartphone. My iPhone X fits easily, leaving enough room for a 10,000mAh portable battery for extra power-ups during the trip.

The lower compartment is much deeper; it ranges from 75 to 90mm (3 to 3.5in) deep, and is about 75mm wide by 180mm long (3x7in). I used that space to carry a compact digital camera, a face mask, and about 500 snack calories in bar form. With a fairly stiff and rigid base, the bag holds its shape well and features a bit of padding to keep electronics safe.

Altogether the SKS Explorer top tube bag I tested weighs 213g.

Bike fit

I had no problem installing this bag with the included straps. The two bottom straps are plenty long to deal with most top tube or front triangle configurations, and there’s a third stem strap to offer side-to-side stability. I was a little worried the bag would flop around due to its height, and the fact that I had so many heavy electronics inside, but it stayed rock solid and needed zero adjustments during my testing.

Like the SKS handlebar bag I reviewed, the Explorer straps have a nice, grippy coating on the underside that’s both anti-slip and anti-scratch.

Fancy features

One of the features that drew me to the SKS Explorer top tube bag is the clear plastic smartphone pouch on top. I knew I would be spending 12+ hours a day on the bike, and who can go that long without looking at their phone? I was surprised that the plastic cover is clear enough to use Face ID to unlock a phone, and it’s also touch-friendly. Oddly SKS chose to add a somewhat raised — but sealed — circle on the cover where one might find a home button on their phone. It appears the latest versions of the bag skip this “feature.”

Inside the top compartment, there’s a piece of mesh and two velcro straps for holding the phone securely. It’s a nice touch and no doubt keeps the phone from flying out when you unzip the compartment, however it does make taking the phone out a bit of a hassle every time you need to use it in handheld mode.

There’s a port at the bottom of the smartphone compartment for running a power cable or wired headphones. Using this seems like it could compromise the waterproofness a bit, and I found the position of the port wasn’t ideal for charging my bar-mounted GPS from the battery pack inside the top tube bag. Instead, I ran the cable from the top and used the handy, dual-end zippers to get the gap where I needed it.

I tested the SKS Explorer in some wet conditions and it kept all of my electronics and my mask dry to the touch. However, visible moisture appeared underneath the plastic cover after about a day of riding, and I was never able to fully eliminate it despite wiping it with a dry cloth regularly. I’m not sure if it was humidity or vapor from water that somehow infiltrated the bag. In either case, it made reading the phone more difficult at times.

Cool factor

Quantifying the cool factor of an item can be difficult, though in this case it’s not, and it’s not, if you catch my drift. I would describe the look as biker geek, but that’s not to say the thing isn’t functional as hell. I will totally take the SKS Explorer on my next bikepacking trip, and even my next local trail ride for the convenience factor alone. At $51.99 it’s a little pricey for such a small bag, though most riders will likely get a lot of use out of it.

Party laps

  • Easy to install on most bikes
  • Two waterproof compartments with good amount of storage
  • Clear top cover for use with a smartphone

Pros and cons of the SKS Explorer top tube bag.

Dirt naps

  • Geek chic
  • Pricey
  • Fogs up in wet or humid conditions