E*Thirteen TRS+ 9-44 Cassette: First Impressions

I recently got my hands on a neat piece of kit from e*thirteen; their TRS+ 9-44 cassette. The cassette comes in three pieces allowing the tiny 9 tooth cog to fit on a standard XD driver.

This box contains some clever: the e*thirteen TRS+ 9-44 cassette, the mounting ring and a mounting tool.

The TRS+ cassette comes in three pieces, which may seem a bit excessive, but it has some upsides. The material of each piece has been selected to minimize weight and maximize longevity. A multi-piece cassette is an elegant approach to mounting the tiny 9 tooth cog on an XD driver. In other good news, apparently each piece will be available separately for purchase meaning you can just replace the damaged or worn piece.

The larger piece mounted to the XD driver.

The larger piece is mounted to an XD drive shell using the black collar shown in the center. The smaller piece is an assembly of two sets of cogs that are screwed together. I was concerned about the smaller 8 gears being cantilevered off small attachment teeth resulting in flex, and potential failure over time. I discovered when installing on the wheel that the inside of the small cluster of 8 gears rides on the outer surface of the XD driver. This made installation more difficult, but should result in a stiffer cassette.

The benefit of the 9-44 cassette results in a total range of 489%, a 16% increase over a standard 10-42 cassette. I’m going to keep using my 30 tooth chain ring on this cassette, should be more than adequate for steep climbs, and good for putting down power to 40 km/hr in top gear.

Match up the brown mark to the open lock, then rotate the smaller cogs using a chain whip till locked. An innovative method to implementing that tiny 9 tooth gear.

I foresee the TRS+ cassette being an interesting replacement for folks. The TRS+ cassette is priced at $300 USD, which is a hair cheaper than a SRAM XG-1180 cassette. The TRS+ cassette is only 5 grams heavier than the XG-1180 at 320 grams, and the TRS+ has a much larger gear range. The TRS+ certainly seems like a well thought out and well positioned product.

The TRS+ mounted on my Norco Range. Cog tooth sizes are; 9-10-12-14-17-20-24-28-32-38-44

I look forward to running the TRS+ cassette on my bike over the coming months. My X1 derailleur is on the limit with the TRS+ cassette on the Norco Range. The Range has more chain growth than most, and I was worried if the X1 derailleur could eat up the slack across the spread of gears. After some setup, the derailleur cage is fully recoiled in the 9 tooth ring at top out, and about as tight as you’d want when bottomed out in the 44 tooth ring. Installing the cassette was tight on my DT Swiss 350 hub, but seems to shift nicely now that it’s installed. I’ll report back on longevity and performance in the coming months.

That 44 tooth ring is going to be a mighty nice bail out gear. At bottom out the chain is just about fully tight. I’d say a spread of 9-44 is about the limit on this derailleur / bike combo.

Is 44 teeth enough for a bailout gear, or would you go even bigger?