Sprint Filter P08 Air Filter for Road & Track – Triumph Bonneville T120 (2017–2026) PM174S

The T120 is the largest engine in the modern Bonneville family, and it breathes through the same airbox as the smallest one. That is normal engineering practice, and also why the intake side is worth a thought here rather than on the 900s. The same box, the same duct and the same element opening have to satisfy a noticeably bigger demand for air, which leaves less margin for anything sitting in the way. The Sprint Filter PM174S is a dry woven polyester element with roughly double the filtering surface of other performance filters, and it goes into the standard box with no modification and no remap.

Key Features

• An 80 µm calibrated aperture, woven from polyester threads of ø 22 microns and upwards
• Rated at 5,050 l/m²/sec, spread over roughly double the filtering surface of other performance filters
• Nothing in the medium is oiled, so no film can reach the air sensor or the throttle bodies
• The standard box takes it unchanged: nothing modified, nothing remapped
• Cleaned from the clean side with an air line, washed when it asks for it, and put straight back in
• Two years of warranty, counted from the date of purchase

More surface in the same space

The airbox is fixed, so the only variable left is how much filtering area is folded into it and how freely that area passes air. Sprint Filter build the P08 as a single layer of woven polyester rather than a pressed cellulose mat, which is what lets them put roughly twice the surface into the same footprint. What the PM174S really offers is that the restriction it starts at is the restriction it is cleaned back to, service after service.

Honest about what it does and does not do

A drop-in element does not make a standard motorcycle noticeably more powerful, and anyone who tells you otherwise is selling something. What it does is keep intake restriction low and, more importantly, keep it stable across the service interval instead of letting it climb as a paper element loads up. On a big torque-led twin that stability lives in the part of the rev range the T120 actually uses — the roll-on in third, not the last 500 rpm.

Care and cleaning

Point compressed air at the clean side and work outwards; the dust then leaves along the path it arrived by, which is the whole idea. Anything the air line will not shift comes off with water and a mild detergent — keep rinsing until the water runs clear. Drying is the step people hurry: open air only, until the element is dry through. Heat and flame have no part in it, and the PM174S goes back into the box dry, with no oil to reapply. The maintenance sheet is in the Downloads tab.

Fitment & Compatibility

Made for the Triumph Bonneville T120, 2017–2026. The same PM174S element covers five machines built around this airbox — the Bonneville T100 and T120, the Street Cup, the Street Scrambler and the Street Twin. The full list with model years is in the Fitment tab.