S&S Cycle Forged Roller Rocker Arms — 1.640:1 — 2017–2025 M8

S&S's forged roller rocker arms for the M8: stronger than stock, easier on the rest of the valvetrain, and — per S&S — essential for longevity on cams with .540 in. or greater lift. Rollers eliminate valve thrusting, and the arms spray oil directly on the valve springs instead of the rocker boxes.

FITMENT

Fits 2017–2025 Harley-Davidson M8 models (S&S). In our catalog: 2017–2025 M8 Touring models. Compatible with stock or S&S CNC heads (S&S).

Not sure it fits your bike? Email info@norcalbaggersupply.com — email is the fastest way to reach us — and we'll confirm before you order. You can also call 916-626-9030 (Mon–Fri, 9 AM–5 PM PT).

CALIFORNIA / CARB

California / CARB: S&S Cycle publishes CARB Executive Order D-355-66 for this part — it is exempt from emissions tampering regulations under that EO and is legal for sale and use in California on the models the Executive Order covers, as well as in all other states.

SPECIFICATIONS

• Manufacturer: S&S Cycle — part number 900-1084
• Forged from 8620 steel; designed using Finite Element Analysis (FEA) — S&S
• Ratio: 1.640:1; capable of .650 in. max valve lift (S&S)
• A must-have for cams with .540 in. or greater lift (S&S)
• Serviceable and rebuildable for long-term durability
• CARB Executive Order D-355-66 (S&S Cycle) — see the California note below
• Made in the USA

INSTALLATION

Rocker arm replacement is top-end work: rocker boxes come off and valve lash/preload is set with adjustable pushrods. Follow the S&S instruction sheet included in the box and your Harley-Davidson service manual. No official S&S install video is published for this part — installation is manual-only. Professional installation is recommended; email us for an install-partner referral.

QUESTIONS RIDERS ASK

When do I need these?
S&S calls them a must-have on cams with .540 in. or more lift — big-lift lobes add side thrust and wear that stock rockers weren't built for. The rollers remove the thrusting and the forged 8620 arms take the stress.

Are they serviceable?
Yes — unlike stock arms, the S&S forged rollers are serviceable and rebuildable (the M8 rebuild kit is S&S part 900-1087).

Can you ship this to California?
Yes. S&S publishes CARB Executive Order D-355-66 for this part, so it is legal for sale and use in California on the models the EO covers — see the California note on this page.