My 2018 Trek Roscoe 8 with 141 Boost Rear Hub.
I have a Trek mountain bike with a 141 boost QR rear axle. Where do I get a replacement hub for it? That's the question I had. Here is what I did to get a 141 boost rear hub for my rear wheel, break that hub and then build a wheel with a much stronger hub to handle my large size — that being 6'7" and 240-pounds.
In 2020, I purchased a 2018 Trek Roscoe 8 that had hardly been ridden. The frame is an XXL, which is a hard size to find but the size I needed to fit me. Two years later in April of 2022 the original rear hub was toast, with the hub's bearings locked up almost solid. At this time, I found out how hard it was to find a decent 141 boost hub to fit this Trek mountain bike.
Trek and maybe other manufacturers decided to go with an odd or should I say, different rear hub setup — the 141 Boost QR rear hub. Aside from cheap China hubs I have found, the only way to get a mainstream name-brand 141 Boost hub is to take a 148mm x 12mm thru-axle hub, remove the end caps and replace them with QR end caps. I did find that DT-Swiss offers some QR end caps for their hubs. I also found the much more affordable yet good quality Sun Ringle SRC 148x12 hub (281-32618-K003) and QR end caps (281-31519-K004) that work to make this a 141 boost hub.
In 2022, I purchased a 32-hole SRC 148x12 rear hub and a 32-hole Sun Ringle Duroc 40 rim. The bike originally came with 28-hole Duroc 40 rims and since I was rebuilding the wheel with a new hub I decided to beef up the strength with 4 additional spokes. While this SRC hub setup worked great, I was a little concerned about the strength of running a thru-axle hub without the thru-axle.
Three years later, my fears came true. The lack of a more robust axle going through the thin aluminum axle sleeve on the SRC hub led to the axle snapping in half on a climb in April of 2025. I believe it was cracked and starting to break for a couple of weeks, given it was starting to behave just a little odd when shifting gears. Anyhow, I was back to finding a solution and wanting to build something stronger.
What my broken axle Sun Ringle SRC rear hub looked like after its last ride.
My snapped axle on a Sun Ringle SRC rear hub.
As I had found a couple of years before, DT-Swiss has some options, but trying to figure out which hub matches with which QR caps was a little challenging and the pricing of their hubs is a little out of my budget, so I decided not to pursue a DT-Swiss.
That put me back to the one Sun Ringle hub option, the SRC 148x12. However, this time I worked out a way to greatly enhance the strength of the hub by using a piece of stainless steel 12mm round tubing, essentially putting a thru-axle through the middle of the hub as it was originally intended to have. After cutting the stainless steel tubing to 5.22" it fit perfectly through the hub and before the final assembly, I coated it with a little grease before inserting it through the hub.
I've ridden over 50 miles on this new beefed-up rear hub and so far, so good. As I get more time on this hub, I'll update this article.
The stainless steel 12mm round tubing I then cut to 5.22 inches long to make an axle for my 141 boost hub.
12mm Stainless Steel tubing cut to length ready for installation, Sun Ringle QR caps and Sun Ringle SRC 148x12 rear hub. The cap on the freehub side threads on with the hole of the QR machined to take an hex key to tighten this cap on. On the brake rotor side, the end cap just snaps on.
This shows the stainless steel 12mm round tubing inserted into my SRC 148x12 hub. I just need to place the brake rotor side QR end cap on and I now have an extra strong 141 boost hub.