SRAM and Shimano currently rule the drivetrain world, but we're starting to see more and more viable options from other manufacturers hit the market. Taiwanese brand, MicroSHIFT, have entered into the ring with their Advent 9-speed derailleur, shifter, and cassette combo. In the past, MicroSHIFT has been more focused on making OEM spec components. Creating specific products to cater to the exact needs of a brand is a good niche to be in and while it may not be the most glamorous, it seems to have done pretty well for them.
MicroSHIFT's Advent drivetrain marks the first time the brand has truly approached a product from the development standpoint. Advent was developed to be functional, durable, and inexpensive. According to the team at MicroSHIFT, the goal with Advent was to give consumers an option that worked well enough you don't think about it while riding while still being pricepoint conscious.
The Advent derailleur, shifter, and 9-speed, 11-42 tooth cassette all together will run you about $125 USD.
The trigger shifter is basic but it feels solid and performs well.
The rear derailleur has a clutch that is easily switched off for wheel removal.
Advent is composed of a shifter, cassette, and derailleur. There currently isn't a crank or chain, and it is chain agnostic - meaning it will work with any 9-speed chain. One challenge with drivetrains, in general, is that the big Red and Blue S's have a lot of patents that must be navigated around, especially when it comes to the rear derailleur.
The Advent rear derailleur doesn't look all that different than any other standard unit at a glance, but its internals are what set it apart. There's a clutch system that can be disengaged for removing the wheel by a switch on the body of the derailleur. It uses a ratchet and pawl system, just like most hubs, but it's different from other major clutch systems which use a friction sleeve. The tension of the Advent's clutch is managed by a friction washer stack that is tightened by a single torx bolt. It's quick to adjust and it's also simple to take apart if it ever needs to be cleaned or repaired.
The shifter is no frills. It's a thumb shift to get into an easier gear and then the trigger shifts into a higher gear. There are sealed bearings in the mechanism to make the shifting smoother and to help ensure shifting with the clutch rear derailleur is easy.
The cassette has an 11-42 range and mates to a standard HG style freehub body. The mass of the gearing is forged steel and the large 42 tooth cog is alloy to help save weight. This cassette is a few teeth shy of the gearing we're seeing from Shimano and SRAM in their high-end systems, but the team at MicroSHIFT claim that they tested out a variety of different options, and while it could be done, the jumps in gear ranges were too big and the quality of shifting with those jumps was compromised once they got above 42-teeth.
The system works with any standard 9-speed chain, something that will run you $15-25 at the most at the local bike shop or online. It's also compatible with any chainring that works with 9-speed chains which is almost everything that's out there right now, bringing your total price in, sans cranks, comfortably under $150 USD.
For sake of comparison, you can find a SRAM X5 9-speed system, which is nowhere near as robust and doesn't have a clutch on the derailleur, for about $115 depending on where you look... pretty comparable in price, not so much in performance. If you were to buy SRAM's 11-speed NX? It's more modern and made for a 1x set up and would run you $196. Shimano's most comparable system, SLX, would be closer at about $170, but it's still a percentage higher.
The 9-speed cassette has a range of 11-42 with the largest cog being alloy to save weight.
If I had paid to replace the X01 derailleur and cassette I trashed, I would have spent $225 on a derailleur and $385 on a cassette, plus a $60 chain...$670.
I would say there's no better way to get some contrast than bolting on the drivetrain to the fanciest test bike I had on hand, so that's exactly what I did. I put the 9-speed Advent on the SB130, complete with those new I9 wheels.
Installing the drivetrain was as straightforward as it could have possibly been. If anything, it was easier to dial in than high-end 11- or 12-speed gearing. One thing worth noting is that the shifter clamp is as basic as it gets. There's no Matchmaker-style compatibility, so I did have to do a bit of finagling and swapping things around to get brakes and shifting where I wanted. Not a big deal, just worth noting. Also worth keeping in mind is that if you have to run a standard HG freehub body.
The first time I went on a ride with the Advent drivetrain, I wasn't sure what to expect. After all, it's a $125 9-speed drivetrain, a far cry from the $670 worth of 12-speed SRAM X01 that I had just taken off the bike but then again, I had tweaked that derailleur and somehow broken a few teeth on the cassette in a bit of a violent and unplanned dismount a few weeks back and it wasn't shifting all that well itself.
I also had some trepidation on running a smaller range in the cassette. I wasn't as much concerned about the jumps between teeth as I was going from the 50 to 42-tooth at the low end of the cassette. I kept in mind that 10 years back we were running what now would be janky 1x set-ups with 34 tooth cassettes and thought nothing of it.
On the trail, I was surprised and impressed with how solid and precise the shifting on the system was. It didn't feel cheap, in fact, each shift felt rock solid. The shifting was smooth and crisp. The trigger shifter took a bit of getting used to, as dropping into a more difficult gear takes a trigger pull - it can't be pushed with the thumb as a Shimano or SRAM shifter can be. I found that the jumps in the 9-speed cassette, larger than we're used to with 11 and 12-speed, were barely noticeable and while there were a couple of times having an easier gear than the 42t would have been nice, it was quite alright.
Descending, there was minimal chain slap or noise. No more than any top dollar drivetrain out there. The clutch seems to do a good job of keeping things quiet. I also didn't experience any dropped chains, and even with the 9-speed chain on the 12-speed Eagle chainring, things were smooth as could be. I'd wager that someone at an S-brand would likely claim this wouldn't be advised/compatible/recommended in staying "brand compliant" but hey, I'm here to tell you that it works fine and doesn't matter.
I've been riding the system for a couple of months now and really haven't taken care of it. I can count on one hand how many times I've lubed the chain and I know that I've done double that many rides in wet conditions. There are minimal signs of wear and everything works just as well as it did when I first installed it.
Shifting, even with a dry chain covered in filth is pretty darn smooth. Volume up for that I9 hub sound that's been asked for.
Is It For You?
The Advent drivetrain fills a previously open spot and meets a need that I think a lot of people have; it's affordable and functional. It is a few dollar tiers below either of the main competitors' most functional entry-level drivetrains, the closest of which I would compare it to is SRAM's 11-speed NX or Shimano's SLX systems. Both of those are a bit more expensive, and while they do have more gearing, I wouldn't say they perform any better when it comes to the smoothness of shifting. The Advent system also seems more robust and capable of handling a little more abuse than either of those systems as well.
If you're a racer or aficionado looking for the lightest set-up, 12 gears, or the crispest shifting you can get, this isn't for you. However, if you're on a budget and are having to debate between new tires and a new drivetrain, you blew all of your money on a fancy bike then ripped the derailleur off on your first ride, or you'd rather go on a trip and have a drivetrain than have to choose one or the other, Advent could be your fix. It's not the lightest setup, and it doesn't have as many gears as some other systems, but it works. It will get you out on your bike and it isn't just a band-aid you'll want to replace when you get a bit more money saved up.
The most value-oriented drivetrains tend to get overlooked, but they do something well – they get you out and riding. I thought that I would be eager to pull this off of my bike and get back to 12-speed, but two months later I've proved myself wrong. Advent works better than it should given its price. It's functional, inexpensive, and bombproof. It's the best option I've ridden for a drivetrain on a budget.— Daniel Sapp