I have got two Streamlined Booms, they are old but haven't broken yet and still work so I'm not changing them.
I like the curve profile and it suits my sailing.

I use various sails, Naish, Ezzy, etc and recently bought a 5.3m Goya Banzai, nice looking sail with a 166cm boom on its top light wind clew ring. I used my 140-190 boom and set it at 26cm extension and I have noticed that on a few sails it always seems too long compared to the printed instructions on the sails.

I reduced the boom to 24cm extension and it seemed to work fine which has also happened to many of my other sails.
It then occurred to me to measure my boom at 24cm extension and guess what, it measures at 166.5cm long.

If anyone is having trouble setting up their outhaul it might be worth actually measuring their boom length.

My booms are 2 cm in the opposite way, I use a boom shim as it's got a STD head but without it they are even more out.

Funny I thought the banzai downhaul adjustment required also boom adjustment. Don't remember any other sail like that.

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Manuel7 said..
Funny I thought the banzai downhaul adjustment required also boom adjustment. Don't remember any other sail like that.

With the Banzai you are supposed to set the downhaul, then adjust with the two clew rings, higher one for lighter winds and lower one for stronger winds. What I am getting at here is that my boom, 140-190 with a 24cm extension measures at 166.5cm and not 164 cm which is what it should be, therefore I have been around 2 cm out on all my sails if I follow their rigging guides.
So the sail recommendations for the Banzai are 166 boom on the top ring. Its about boom length not being right.

I have had two or three different booms that the numbers on the boom don't match the sail manufacturer specs.just have to adjust in or out to make it right my current boom Goya seems to match up with my older simmers or some naish sails that I have

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KDog said..
I have had two or three different booms that the numbers on the boom don't match the sail manufacturer specs.just have to adjust in or out to make it right my current boom Goya seems to match up with my older simmers or some naish sails that I have

Have you ever measured your boom at a set extension to see what.
Firstly, what it says on the boom. ( say 26). and.
secondly what it actually measures. ( 168cm ) then its around 2cm out.

I've never had the numbers written on my streamlined extension?!

For sure boom and mast extensions markings will vary. Actually most everything will, mast, caps, sail, best to get reliable visual cues.

I ignore printed numbers on booms, extensions, sails, everything.

Just rig it and adjust it until it is correct. This might require some on-water verification. When it is right, make a rigging chart and write down the number of holes or slots or whatever things you can count. Next time you rig, just use those settings from your chart.

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segler said..
I ignore printed numbers on booms, extensions, sails, everything.

Just rig it and adjust it until it is correct. This might require some on-water verification. When it is right, make a rigging chart and write down the number of holes or slots or whatever things you can count. Next time you rig, just use those settings from your chart.

I would not ignore printed numbers, if they are on the boom and extension. They will get you close using the numbers on the sail, and then you adjust by eye to get it right like segler says and remember the setting. Also, even if your boom numbers are correct, the sail may require more/less downhaul/outhaul then stated, the manufacturer's number are not always correct according to what one manufacturer told me. Then on my Streamlined extensions I can see the ring marks after a few uses at the same setting, and that "mark" is where I put the ring next time keeping in mind then number too for a given sail.