Fitting Instructions - STK-010 BSA B50, B44, B40/25, C15

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Kit Contents

Stator
Rotor
Spacers
Combined HT-CDI unit

Fitting Instructions

1. Remove the original stator & rotor from left hand cover.



2. The rotor supplied (type IR10) has 2 keyways.Keyway A is for B44/50 and military B40’s.Keyway B is for B40/B25/C15.Fit the new rotor (see fig 2), the supplied spacer should be used where a stepped retaining nut is not available, fully tighten.



3. Place the 3 spacers provided on the studs, leaving in position the original spacers and chain tensioner (see fig 2).



4. Fit the new stator as shown (see fig 3) with stainless steel retaining plate outermost.



5. Feed cables through crank case, (fig 4.). Locate HTCDI and connect the terminals from the stator. Black cable connects to the small terminal. Blue cable with Black/white connects to the large terminal.
   Note: Black/white cable is for connecting to a kill switch. When connected to earth the engine will stop.



6. Setting the timing (see fig. 3),
   Position shown is for the start of sparking, total advance for this system is 27 degrees,
   so if the maximum advance is 34 degrees (B50/B44) set the piston to 7 degrees BTDC.
   
   0.34mm BTDC (or 7 degrees) for B50/44 engines with 90mm.
   0.26 mm BTDC (or 7 degrees) for the B40, B25, C15 engines with a 70mm stroke.
   
   
7. Tighten retaining nuts for the stator ensuring that there is an even air gap with the rotor.



8. Re-check timing is correct.

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