2 choices
You can do this 2 ways, if you want to roller-reef the mainsail, you will need to either temporarily not use the mid-boom block (I assume your boat has the older end-boom sheeting with a block at mid-boom to lead the sheet to the block and cam-cleat on the CB trunk?) or move the mid-boom block to a reefing claw. If you have a newer Javelin with mid-boom sheeting (that is the whole mainsheet is at mid-boom), then you will need to use a reefing claw for that block. Due to the fact that I see very few reefing claws advertised in marine stores these days, I'd recommend having a sailmaker install a set of "reefpoints" on your sail allowing you to use "slab" or "Jiffy" reefing. This is a much better way to reef, since the sail shapes better and the sail won't have to cover the block. The roller-reefing on the small O'Days was a great Idea, but I never really liked it on my DS II.
