Really pleased with the Atlas and feel this model is quite unique. Mine arrived in August 2022 and it’s working very well. I’m very impressed with the range of the standard battery. I run PAS #1 probably 95% of the time on mostly flat paved trails and I can easily get 50 miles with 15-20% battery left. The wife’s Omega uses the same battery but she typically runs PAS #2 in order to keep up and her battery is spent at 50 miles.


  • Handling, brakes, riding position are excellent.
  • Headlight and brake lights work well (but I don’t ride at night)
  • This bike feels solid at speed
  • The tire size is great for a lot of surfaces without being a “fat tire bike”
  • Battery range is excellent (our previous Aurora’s would max out around 30 miles).
  • The 48V/3A battery charger (Atlas & Omega) provides a quicker charge than our previous ebikes
  • PAS #1 really provides too much assist for casual riding with friends (especially if they are riding regular bikes). And that’s with my settings at 9 levels of pedal assist. It propels me to 15+ mph with little effort.
  • I would like higher gearing. Low gear seems too low for an ebike and at high gear, your cadence is pretty fast at 20+ mph. (I might consider a sprocket change)
  • All high price ebikes should have a removable display or ignition switch to ‘lock out’ the electronics when unattended.
There are a number of ebikes using the Gates belt and Enviolo hub combination, but from what I’ve seen, most are more expensive and are predominantly pedalecs (no throttle).
I wanted a belt drive ebike (no chain & derailleur) and a throttle was mandatory. Most of Evelo’s models have these features and I considered the Aurora LE and the Omega. (the wife and I had Aurora’s but they developed persistent motor noises so they were returned). I got the Atlas and Omega for her.
Totally agree with the high cadence at 20+ mph. Interested in your results if you do the sprocket change.
Totally agree with the high cadence at 20+ mph. Interested in your results if you do the sprocket change.
The Atlas uses a 55/26 sprocket combination with a 128T belt (Gates CDX series). And the 55T front sprocket appears to be the largest available with the 4 bolt mounting pattern, therefore a smaller rear sprocket is the only way to get higher gearing. Unfortunately, there is only about 5/8" of travel available for belt tensioning so any sprocket change will require a shorter belt (although a 24T rear sprocket might barely work). I'm going with a 22T sprocket and a 125T belt, which according to the Gates calculator should work. I'll update this post when I get the parts installed. See the link below for the calculator worksheet.
Front Sprocket = 55T (CT11554AA) (SI-3821)
Rear Sprocket = 26T (CT1126VMN) (QF-2221)
Belt = 128T (11M-128T-12CTS)

Finally got everything together and installed the 22t rear sprocket and 125t belt. Had to run the belt adjustment to the minimum center distance but it just fit.
Original ratio was 55/26 = 2.12, now 55/22 = 2.50. Sunny and in the 40's so I got out and put on a few miles and I like the change. With the original 55/26 combo, I rarely used the lower half of the gear range and was always grabbing for more at the top end. With this new gearing it feels like I'll spend more time in the upper mid range rather than topped out. I did get on a slight downhill at 30 mph in top gear and didn't feel like the wicked witch of the west!
Thanks for the R&D, KnobbyGuy. I just bought an Atlas and used your experience to order the replacement parts today for the gear ratio upgrade. Swapping this out is at the upper end of my mechanical limits but I think I can do it. Gates has a couple of videos that show how to pull and replace Surefit sprockets. I'm psyched but fingers are crossed that i don't mess this up.
Take a few pictures of the hub/sprocket before the swap. It's important to get the sprocket completely seated onto hub before re-installing the snap ring. The snap ring is a little tricky because it doesn't have the traditional tabs like the flat style. It MUST be seated completely in the groove to avoid problems and it won't seat completely unless the sprocket is correct. Take a good look at the snap ring before removing it and note the gap between the two ends. That gap is a good indicator to tell if the ring is fully seated. (my first Aurora was mis-assembled at the factory and the snap ring was never seated properly, so even they had problems - Evelo immediately sent me all the necessary parts to fix it).
You also have to split the frame at the special joint (2 allen screws) to remove the belt. That joint doesn't naturally want to separate so it has to be pried open as you slide the belt through. I used a large screwdriver at one end of the joint to hold it apart, started the belt through the gap, then reinserted the screwdriver on the other end of the joint and removed the belt.
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As for an update: I'm quite happy with the performance of the 55/22 sprocket combo. I still rarely use the lower gear ratios, they simply aren't needed with an ebike for my type of riding. I think I would go to a higher ratio if I could, but I am satisfied that I made the change.
Thanks for the tips. Both sound tricky/subtle but essential to making it work. I never considered that the frame joint wouldn't want to open.