Hi Yes most defiantly i had a 85Xi with the magnets in the wrong place and thus the timing was all screwed but it being my first gas engine and i did not know what i was doing it took 18 months for me to find out why it was such a bad starter.
It was resolved when the 3W ignition died and i bought a rexel as a replacement and i had to re-time the engine and bingo there was the problem it is now great, but at the time extremely frustrating.
I left the magnets in place and re drilled the senser to a new position.
Set the timing at 28 degrees before TDC you may like me have to reposition the sencer.
Dave.