There is a transition going on in Waterloo, Wisconsin and we’re taking notice. Slowly, the Bontrager apparel is wearing the Trek badge and moving to solid, stylish colors with muted branding. This change does put their apparel inline with current trends, but can conjure up the Kit Police in certain circles. That being said, the straightforward Trek Circuit Thermal Long Sleeve Jersey is easy on the wallet and capable on cold rides.
Trek Circuit Thermal Long Sleeve Jersey Features:
- Thermal fleece fabric provides breathability and moisture management
- HeiQ Fresh silver-free technology provides effective odor control
- Ribbed fabric provides a just-right stretch that moves with your body
- Full-length YKK zipper for customized ventilation on long climbs
- Zippered side security pocket keeps your valuables secure
- This product saves the equivalent of 63 PET plastic water bottles
- Fitted cut provides streamlined body fit for enhanced performance
- Colors: Black or charcoal (tested)
- MSRP: $119.99

Warm alone or layered — in the right temps
For the most part, the Trek Circuit Thermal Long Sleeve Jersey has been used as a mid-layer on cold rides this winter. With a brushed lining and a smooth face, the Circuit Thermal keeps things cozy while also breathing well. Comparable in function to the MAAP Training Thermal LS Jersey, but at a fraction of the price.
Zipping up the Circuit Thermal, you can get a taste for where Trek is going with it. The fit is definitely racy, but on par with their other kits these days. I can also appreciate the tall collar, and found it to work best with jackets without a tight collar. One that has worked well with it is the Pearl Izumi PRO NeoShell WxB Jacket, for example. Combined, the two collars become impervious to the elements and provide excellent warmth on even the coldest rides. I do find I have to re-adjust the collar height though, as it does tend to bunch up in the back.

At the top of the mid-height collar, the zipper tucks into a little garage. This does ensure that my chin doesn’t endure the scratchy end of the top of the zipper, but also completely envelops the zipper pull — thus making it nearly impossible to find with or even without winter gloves. A little extra length on the zipper pull or a more minimalist garage would be preferred. Once you do access the zipper, it pulls easily to allow increased ventilation or warmth, as needed.
The cuffs and underarms utilize a ribbed material for added stretch. The cuffs seal off the elements quite well and are compatible with gloves and jacket cuffs. Added sleeve length is fantastic and provides perfect wrist coverage.

Utilizing a polyester/elastane blend, Trek has chosen to add HeiQ Fresh for added odor control. It seems to work quite well as the Circuit Thermal can withstand a few rides before a washing becomes necessary.
Jersey pockets are mandatory and these are certainly adequate for winter rides. They are a little small, but do feature pleats to swallow more items than I originally thought. Plus, there is a separate zippered sleeve on the right side for credit cards or a small wallet.

The materials breathe really well alone and as expected when used as a mid-layer. Warmth is good and I’d expect to be able to wear this alone in the 50’s and layered in the 30’s and 40’s. On the coldest rides, I’d prefer something like the Pearl Izumi PRO Alpha Layer due to the added loft and warmth of the Polartec Alpha material (it’s bonkers). I have worn it exclusively with the Trek Circuit Thermal Bib Tights for an affordable and warm winter kit.
Fit: I’m 5’11” and 173 lbs, wearing the size medium (as expected with Trek/Bontrager kits).
The Good
- Form-fit design
- Jersey pockets are easily accessed
- Tall collar adds warmth
- Nice sleeve length for proper coverage
- Ribbed cuffs and underarms stretch to add comfort
The Bad
- Collar tends to bunch up and fold on itself
- Zipper pull gets lost in the
The Bottom Line: Trek Circuit Thermal Long Sleeve Jersey
For the money, this is a great cool and cold-weather jersey. It doesn’t have the loft of other winter jerseys, but offers a sleek, functional fit as a standalone jersey during shoulder season and layered up when added warmth is needed. The tall collar is good overall, but does tend to bunch up and hide that zipper. Sleeve length is just right and the ribbed cuffs offer a stretchy, simple solution to keeping weather at bay.
Buy Now: Visit TrekBikes.com