Useful Information
Where does it fit… And what does it fit?
The M5 replaces the standard Recoil Start Housing at the Magneto end of the 2 Cylinder Rotax range of engines designed for aviation, snowmobile, skidoos and hovercraft. It will fit the following engines – 377, 447, 462, 503, 508, 532, 582.
Uniquely, you can mount the M5 in any position possible now. We supply (free of charge) a laser cut, steel drilling template that allows you to decide the best orientation for your M5, avoiding engine mounts etc. while ensuring accurately located mounting holes. The only constraints being the cylinder barrels/heads and fan housing. Full instructions are provided in the comprehensive downloadable manual in pdf format.
You will automatically receive a copy upon receipt of your order, but you can download a copy free of charge direct from this site. The manual is updated as and when changes in design occur so you will always receive the latest version.
Installation Tips
Fan Housing Clearance
If you are fitting an M5 to a fan cooled Rotax, you will need to cut a small radius out of the backplate to clear the fan housing. We supply an additional steel template that you can use with the drilling template to achieve a neat solution. This too, is FOC with the kit.
Battery Type
The starter motor has a Cold Cranking Current (CCA) of 90 amps. We suggest you fit a battery with a rated CCA of around 130 amps to allow some margin. Lithium type batteries are available with double the suggested CCA yet weigh less than 2 Kg.
Solenoid
ANY motorcycle type solenoid with a rating of 100 amps should be fine. Ebay is a major source but beware of the ultra cheap jobs, they can be of very poor quality. Most motorcycle solenoids are lightweight.
Earth Terminal
The M5 is sufficiently conductive via the motor retaining screws. You should consider an earth strap from a convenient point on the engine crankcase to the Negative Terminal of the battery.
Fitting the belt
When you mount the M5 backplate and motor, it can help to leave the 4 M6 mounting screws a little loose so that you can pull the motor end away from the crankcase. This will ease mounting of the toothed belt because there is no adjustment for belt tension, which is correct when the Backplate is fastened to the engine.
Support Bracket
The BMAA and the LAA demand a support bracket from the motor body to the engine. It’s not possible to offer a generic design, due to the endless mounting options. However, a number of owners have used ‘U’ type exhaust brackets (the motor is 63mm in diameter) combined with aluminium or steel bar and either fixed to the crankcase or the motor mounts. Another option is to use 63mm glass reinforced pipe clamps. These incorporate a simple clamp which can be undone should the M5 need to be removed, without disturbing the entire bracket.