Service bulletin M1650

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

NHTSA's summary

SERVICE BULLETIN M1650: MILWAUKEE EIGHT AND TWIN CAM CAMSHAFT DRIVE GEAR RETENTION KIT CHANGES. PURPOSE: This bulletin informs dealers that changes have been made to the Camshaft Drive Gear Retention Kit and service proceduresfor the Milwaukee-Eight and Twin Cam applications. In an effort to increase the clamp load of the camshaft drive sprocket bolted joint and prevent the drive bolt from loosening in high lift camshaft applications, the following changes have been made: a. The camshaft drive bolt final torque has been increased to 40 ft-lbs (54 N·m) for all Milwaukee-Eight and certain Twin Cams models. See Vehicles Affected. This increase in torque will make the bolt a one time use application. Never re-use a camshaft drive bolt for service after tightening to the increased specification. See service manual for updated procedure. b. A new camshaft drive gear retention kit (Part No. 91800088) has been created. This new kit is compatible with all Milwaukee-Eight and Twin Cam engines using Parts and Accessories (P&A) camshaft and Original Equipment (OE) camshaft applications. See Instruction sheet for specific fitment on Twin Cam OE camshaft applications. The new kit utilizes friction washers to prevent unwanted rotation of components in the drive sprocket bolted joint under stress. The use of liquid threadlocker on the threads of the bolt and pre-lube to the head of the bolt flange and outside of the washer help the bolt reach full stretch when tightening. NOTE: Engines produced at all Harley-Davidson Motor Company (HDMC) plants will not come with the new kits installed. They will continue to be produced with (Part No. 25566-06).

The document

• NHTSA's copy of the document (PDF)
• If that address does not open, try this one

The document is the manufacturer's. This site does not hold it. NHTSA files a document at one of these two addresses; we have not asked NHTSA which.

Components

Engine, Fuel system, Throttle and cruise control, Transmission and driveline

Listing a model year does not mean every vehicle of it is concerned: the document says which.

• Bulletins for another vehicle
• Report an error on this page
• Report an error by email