Oil changed in shock, lighter HSC spring, undesirable results

[oldtimemxer58]

Just serviced my shock. I changed the oil and I replaced the stock "high speed compression damping" spring for a lighter one advertised by Moto Pro Suspension in Redmond Wa. The lighter spring is purported to alleviate the harshness of this circuit. I was just trying it to see if it might help a high speed deceleration headshake problem. But it has had an adverse effect of bottoming. I don't know maybe it has some air in there causing this. I have read any air would cause expansion when hot noticable by the bike not having any "unladen" sag because of this expansion. I have not noticed this yet. I really need to test ride it one more time as I socked the adjuster all the way firm now. I'm afraid to ride it hard though as it "spiked" my back one time when it bottomed. Anyone else tried any modifications with this circuit. Or just serviced the shock and how did it go? Its a bugger to get the air out but I could have swore I did it. Any feedback from the mechanics out there would be great. Thanks ahead.

Track junkie Oldtimemxer58