I have had a similar problem and needed to beech the boat more than once to release the genniker. Even then I could not see any reason why it was jambing so I have stopped using this sail. If anyone can suggest a remedy I will be delighted to try it out.
Couple of things which might help.......on the top patch tie a bowline about 10 - 12 inches long...this will stop the sail 'bunching' as it enters the chute/bag as it sounds like that is what is happening.......also spray some lubrication around the chute opening (maclube or something similar). The other thing is to really go for it on the drop, get the kite in quickly....
Others I am sure will have some thoughts but keep asking !
Ashley, Neil's point is a good one - makes it much easier. Get along to the Nationals at Lymington and I'm sure everyone will be happy to help out.
Sometimes you'll find that the halyard re-cleats itself when you're trying to retrieve it. So that's the first thing to visibly check. And you might have to yell at the crew to get his foot off the halyard/downhaul !
Lastly, I would enlist the help of a member of your sailing club, who you know to be proficient using an asymmetric spinnaker, get him/her to accompany you for a short sail and help check it out.
Tried out advice from Neil last night and had about a dozen drops without encountering any problems. As I had previously been lubricating the bag, it would seem to be the long bowline on the top patch that resolved the problem.
Discussed this with experienced sailors at the club as the reason for the success was not immediately apparent to me. The conlusion/reaon being that by using a long bowline, the knot itself pulls on the patch ring keeping it separate from the top patch when dropping the sail - this has the effect of reducing the 'bunching' as the sail is drawn into the bag.
Just a couple of suggestions to look at check the small block under the shut at the bow has not burnt or failed which causes more drag (i had to replace mine with a better ball race type and slightly larger Harken), secondly are you taking up the slack on the down haul before releasing the main cleat.
Glad it worked....one other point put a 'bobble' under the knot to stop it getting pulled through.....looks like the weather could be perfect this weekend !