Sprint Filter P08 F1-85 Air Filter for Racing – Royal Enfield Bullet B5 500 EFI (2011–2026) CM195S F1-85

Flow ratings describe what a medium can pass. They say nothing about what an engine asks for, and that is where this element has to be judged. A 500 cm³ single draws its air in one intake event every two revolutions, and the volume it needs sits far below what the standard 80 µm weave already supplies. The CM195S F1-85 raises the ceiling from 5,050 to 15,000 l/m²/sec per square metre of cloth — three times the headroom above a demand that was not reaching the old ceiling either.

Key Features

• Dry polyester racing medium, filtering at 85 µm
• Rated flow of 15,000 l/m²/sec, roughly three times that of the standard P08 weave
• 95.22 % of the 100-micron particles retained in Sprint Filter's comparison measurement
• Around twice the filtering area of other performance elements, in the unmodified series airbox
• Never oiled, washable, and specified to last the life of the motorcycle
• Direct fit for the 2011 to 2026 machine, with two years of warranty

The number and the need

Capacity only becomes visible when something demands it: sustained full throttle, held high in the rev range, repeated until the intake is the part of the system under pressure. That is a description of a race track, and a standard Bullet B5 does not produce it on any road. This is not a shortcoming of the element — it is what the medium was designed for, and Sprint Filter puts the intended use in the name rather than hiding it.

The honest arithmetic

This element lists at roughly three and a third times the standard P08 for the same airbox, one of the widest gaps anywhere in the Sprint Filter range. That gap is paid for a flow figure this motorcycle cannot use, so for a road-going B5 the recommendation is the standard weave, and this page will not pretend otherwise. The racing cloth would not add power in any case: a drop-in filter does not make a standard machine noticeably stronger, whatever it is woven from. Where the F1-85 belongs is a machine that runs sessions rather than journeys.

Care and cleaning

Dry servicing, exactly as for the rest of the range: an air line held on the clean face of the CM195S F1-85 and worked outwards until the weave looks even again. Water and a mild detergent are for greasy contamination only, followed by a proper rinse. Drying happens in open air with no heat at all — no gun, no oven, no flame — and the element goes back untreated. The maintenance sheet is in the Downloads tab.

Fitment & Compatibility

For the Royal Enfield Bullet B5 500 EFI, 2011 to 2026. The same racing element is listed against the Bullet Trials 500 EFI of those years, the Classic 500 of 2009 to 2020 and the 535 cm³ Continental GT35 EFI of 2015 to 2018. Confirm your year in the Fitment tab before ordering.